Jun. 2018, The Institute of Electronics, Information and Communication Engineers of JAPAN, 2017 Best Paper Award　　　　　　　　　　　　　　　
Linear Quadratic Regulator with Decentralized Event-Triggering
K. Nakajima;K. Kobayashi;Y. Yamashita

Implicit Control Lyapunov Function Design for Nonlinear Systems with Symmetry under Feedback　　　　　　　　　　　　　　　
Yuh Yamashita, Koichi Kobayashi
SICE Journal of Control, Measurement, and System Integration, 2026, [Peer-reviewed], [Lead author]
English, Scientific journal

Online Optimization of Pickup and Delivery Problems Considering Accident Recovery Forecast　　　　　　　　　　　　　　　
Soma Nakagawa, Koichi Kobayashi, Yuh Yamashita
Artificial Life and Robotics, 2026, [Peer-reviewed], [Last author]
English, Scientific journal

Event-Triggered Model Predictive Control of Distributed Network Systems with Switching Topologies
Masaki YANAI, Koichi KOBAYASHI, Yuh YAMASHITA
IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences, E109A, 5, Institute of Electronics, Information and Communications Engineers (IEICE), 2026, [Peer-reviewed], [Last author]
English, Scientific journal

Switching Control with Signal Temporal Logic Specifications for Pedestrian Flows Using Discrete Hughes Models
Akihiro MORITA, Koichi KOBAYASHI, Yuh YAMASHITA
IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences, E109A, 5, Institute of Electronics, Information and Communications Engineers (IEICE), 2026, [Peer-reviewed], [Last author]
English, Scientific journal

Vehicle Platooning Based on Second-Order Pinning Consensus Control and its Cyber Attack Detection
Ikumi Kidokoro, Koichi Kobayashi, Yuh Yamashita
Journal of Robotics and Mechatronics, 37, 5, 1087, 1093, Fuji Technology Press Ltd., 20 Oct. 2025, [Peer-reviewed], [Last author]
English, Scientific journal, In this paper, we propose a vehicle platooning method based on pinning consensus control and its cyber attack detection. The consensus problem, in which the state of each agent is matched through communications, is a well-known control problem. Pinning control is a method of adding external control inputs to pre-specified agents called pinning agents. This control method can set the state of an agent to a value other than its initial average value or increase the rate at which it converges. Model predictive control (MPC) involves obtaining control inputs by solving the finite-time optimal control problem at each discrete time. Using pinning consensus control and MPC, we consider vehicle group control, in which multiple vehicles are controlled as a single group. In addition, a method for detecting cyber attacks on pinning agents is also proposed.

Control Barrier Function Construction for Systems with High Relative Degree via Level Surface Design
Takuma Harada, Yuh Yamashita, Koichi Kobayashi
IECON 2025 – 51st Annual Conference of the IEEE Industrial Electronics Society, IEEE, 14 Oct. 2025, [Peer-reviewed]
English, International conference proceedings

Event-Based Asynchronous Update of Control Input and Sampling Interval for Cyber-Physical Systems
Shota NAKAYAMA, Koichi KOBAYASHI, Yuh YAMASHITA
IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences, E108.A, 10, 1366, 1372, Institute of Electronics, Information and Communications Engineers (IEICE), 01 Oct. 2025, [Peer-reviewed], [Last author]
English, Scientific journal

Online Optimization of Pickup and Delivery Problems Considering Traffic Congestion Prediction
Soma Nakagawa, Koichi Kobayashi, Yuh Yamashita
2025 IEEE 14th International Conference on Consumer Electronics - Berlin (ICCE-Berlin), 144, 148, IEEE, 06 Sep. 2025, [Peer-reviewed], [Last author]
English, International conference proceedings

State-Flipped Control for Probabilistic Boolean Networks Using Deep Reinforcement Learning　　　　　　　　　　　　　　　
Tatsuya Hasegawa, Koichi Kobayashi, Yuh Yamashita
Proc. of SICE Festival 2025 with Annual Conference, Sep. 2025, [Peer-reviewed], [Last author]
English, International conference proceedings

A Reinforcement Learning Approach to Event-Triggered Control of Probabilistic Boolean Networks with Multiple Control Inputs　　　　　　　　　　　　　　　
Keito Matsuoka, Koichi Kobayashi, Yuh Yamashita
Proc. of SICE Festival 2025 with Annual Conference, Sep. 2025, [Peer-reviewed]
English, International conference proceedings

Collision Avoidance Control of Four-Wheeled Vehicles Using Control Barrier Functions and Linear Programming　　　　　　　　　　　　　　　
Kohta Banshodani, Yuh Yamashita, Koichi Kobayashi
Proc. of SICE Festival 2025 with Annual Conference, Sep. 2025, [Peer-reviewed]
English, International conference proceedings

Cyber Attack Detection in P2P Energy Trading Using Machine Learning　　　　　　　　　　　　　　　
Wenxuan Xu, Koichi Kobayashi, Yuh Yamashita
Proceedings of 2025 IEEE 14th Global Conference on Consumer Electronics, Sep. 2025, [Peer-reviewed], [Last author]
English, International conference proceedings

On Reconstruction of Boolean Networks Using Input-Output Data Sets　　　　　　　　　　　　　　　
Xiaoniujin Chen, Koichi Kobayashi, Yuh Yamashita
Proceedings of 2025 IEEE 14th Global Conference on Consumer Electronics, Sep. 2025, [Peer-reviewed], [Last author]
English, International conference proceedings

A Common Lyapunov Function Approach to Event-Triggered Control with Self-Triggered Sampling for Switched Linear Systems
Shota NAKAYAMA, Koichi KOBAYASHI, Yuh YAMASHITA
IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences, E108.A, 4, 575, 581, Institute of Electronics, Information and Communications Engineers (IEICE), 01 Apr. 2025, [Peer-reviewed], [Last author]
English, Scientific journal

Analysis of Security Indices in Hybrid Cyber Attacks of Power Network State Estimation
Yuta Kajinishi, Koichi Kobayashi, Yuh Yamashita
2025 IEEE International Conference on Consumer Electronics (ICCE), 1, 4, IEEE, 11 Jan. 2025, [Peer-reviewed], [Last author]
English, International conference proceedings

Vehicle Platooning Based on Second-Order Pinning Consensus Control and Its Cyber Attack Detection
Ikumi Kidokoro, Koichi Kobayashi, Yuh Yamashita
2025 IEEE International Conference on Consumer Electronics (ICCE), 1, 4, IEEE, 11 Jan. 2025, [Peer-reviewed]
English, International conference proceedings

Linear Matrix Inequality-Based Design of Structured Sparse Feedback Controllers for Sensor and Actuator Networks
Yuta Kawano, Koichi Kobayashi, Yuh Yamashita
Algorithms, 17, 12, 590, 590, MDPI AG, 21 Dec. 2024, [Peer-reviewed], [Last author]
English, Scientific journal, A sensor and actuator network (SAN) is a control system where many sensors and actuators are connected through a communication network. In a SAN with redundant sensors and actuators, it is important to consider choosing sensors and actuators used in control design. Depending on applications, it is also important to consider not only the choice of sensors/actuators but also that of communication channels in which some sensors/actuators are connected. In this paper, based on a linear matrix inequality (LMI) technique, we propose a design method for structured sparse feedback controllers. An LMI technique is one of the fundamental tools in systems and control theory. First, the sparse reconstruction problems for vectors and matrices are summarized. Next, two design problems are formulated, and an LMI-based solution method is proposed. Finally, two numerical examples are presented to show the effectiveness of the proposed method.

Temporal Logic MPC of Spatially Distributed Systems Considering Feasibility
Ikkei Komizu, Koichi Kobayashi, Yuh Yamashita
2024 IEEE 13th Global Conference on Consumer Electronics (GCCE), 700, 701, IEEE, 29 Oct. 2024, [Peer-reviewed], [Last author]
English, International conference proceedings

Introducing Event-Based Communication in Asynchronous Advantage Actor-Critic Algorithm
Hiroki Sunai, Koichi Kobayashi, Yuh Yamashita
2024 IEEE 13th Global Conference on Consumer Electronics (GCCE), 494, 495, IEEE, 29 Oct. 2024, [Peer-reviewed], [Last author]
English, International conference proceedings

State-Flipped Control for Probabilistic Boolean Networks Using Reinforcement Learning
Tatsuya Hasegawa, Fuma Motoyama, Koichi Kobayashi, Yuh Yamashita
2024 IEEE 13th Global Conference on Consumer Electronics (GCCE), 702, 703, IEEE, 29 Oct. 2024, [Peer-reviewed], [Last author]
English, International conference proceedings

Model Predictive Control of Spatially Distributed Systems with Spatio-Temporal Logic Specifications
Ikkei Komizu, Koichi Kobayashi, Yuh Yamashita
Computation, 12, 10, 196, 196, MDPI AG, 30 Sep. 2024, [Peer-reviewed], [Last author]
English, Scientific journal, In this paper, for spatially distributed systems, we propose a new method of model predictive control with spatio-temporal logic specifications. We formulate the finite-time control problem with specifications described by SSTLf (signal spatio-temporal logic over finite traces) formulas. In the problem formulation, the feasibility is guaranteed by representing control specifications as a penalty in the cost function. Time-varying weights in the cost function are introduced to satisfy control specifications as well as possible. The finite-time control problem can be written as a mixed integer programming (MIP) problem. According to the policy of model predictive control (MPC), the control input can be generated by solving the finite-time control problem at each discrete time. The effectiveness of the proposed method is presented through a numerical example.

A BDD-Based Approach to Finite-Time Control of Boolean Networks
Fuma MOTOYAMA, Koichi KOBAYASHI, Yuh YAMASHITA
IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences, E107.A, 5, 793, 798, Institute of Electronics, Information and Communications Engineers (IEICE), 01 May 2024, [Peer-reviewed], [Last author]
English, Scientific journal

Lyapunov-based approach to event-triggered control with self-triggered sampling
Shota Nakayama, Koichi Kobayashi, Yuh Yamashita
Advanced Robotics, 38, 9-10, 603, 609, Informa UK Limited, 28 Feb. 2024, [Peer-reviewed], [Last author]
English, Scientific journal

On reward distribution in reinforcement learning of multi-agent surveillance systems with temporal logic specifications
Keita Terashima, Koichi Kobayashi, Yuh Yamashita
Advanced Robotics, 38, 6, 386, 397, 14 Feb. 2024, [Peer-reviewed], [Last author]
English, Scientific journal

Online Optimization of Pickup and Delivery Problem Considering Feasibility
Ryo Matsuoka, Koichi Kobayashi, Yuh Yamashita
Future Internet, 16, 2, 64, Feb. 2024, [Peer-reviewed]
English, Scientific journal

A BDD-Based Approach to Model Reduction of Boolean Networks
Fuma Motoyama, Koichi Kobayashi, Yuh Yamashita
IEEE Transactions on Control of Network Systems, Early Access, 2024, [Peer-reviewed], [Last author]
English, Scientific journal

Reinforcement Learning for Multi-Agent Systems with Temporal Logic Specifications
Keita TERASHIMA, Koichi KOBAYASHI, Yuh YAMASHITA
IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences, E107-A, 1, 31, 37, Institute of Electronics, Information and Communications Engineers (IEICE), Jan. 2024, [Peer-reviewed], [Last author]
English, Scientific journal

Multi-Agent Surveillance Based on Travel Cost Minimization
Kyohei MURAKATA, Koichi KOBAYASHI, Yuh YAMASHITA
IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences, E107-A, 1, 25, 30, Institute of Electronics, Information and Communications Engineers (IEICE), Jan. 2024, [Peer-reviewed], [Last author]
English, Scientific journal

Finite-Time Control of Boolean Networks Using Binary Decision Diagrams　　　　　　　　　　　　　　　
Fuma Motoyama, Koichi Kobayashi, Yuh Yamashita
Proc. SICE Annual Conference 2023, 145, 148, Sep. 2023, [Peer-reviewed], [Last author]
English, International conference proceedings

Redesign of Control Lyapunov Functions of Nonlinear Systemswith Symmetry under Feedbacks　　　　　　　　　　　　　　　
Yuh Yamashita, Koichi Kobayashi
Proc. SICE Annual Conference 2023, 411, 414, Sep. 2023, [Peer-reviewed], [Lead author]
English, International conference proceedings

Lyapunov Function-Based Approach to Event-Triggered Control with Self-Triggered Sampling
Nakayama Shota, Kobayashi Koichi, Yamashita Yuh
Proc. of the 2023 International Symposium on Nonlinear Theory and Its Application, 467, 470, Sep. 2023, [Peer-reviewed], [Last author]
English, International conference proceedings

LMI-Based Design of Structured Block-Sparse Output Feedback Controllers for Sensor and Actuator Networks　　　　　　　　　　　　　　　
Yuta Kawano, Koichi Kobayashi, Yuh Yamashita
Preprints of the 22nd IFAC World Congress, 1481, 1484, Jul. 2023, [Peer-reviewed], [Last author]
English, International conference proceedings

Reinforcement Learning for Multi-Agent Systems with Temporal Logic Specifications　　　　　　　　　　　　　　　
Keita Terashima, Koichi Kobayashi, Yuh Yamashita
Preprints of the 22nd IFAC World Congress, 1509, 1512, Jul. 2023, [Peer-reviewed], [Last author]
English, International conference proceedings

Vehicle Platooning at Intersection Based on Self-Triggered Pinning Consensus Control　　　　　　　　　　　　　　　
Ayaka Tanaka, Koichi Kobayashi, Yuh Yamashita
Preprints of the 22nd IFAC World Congress, 5026, 5028, Jul. 2023, [Peer-reviewed], [Last author]
English, International conference proceedings

Automatic Generation of Control Lyapunov Functions for Vehicle Guidance on Complex Paths
Yuh Yamashita, Wataru Hashimoto, Koichi Kobayashi
IFAC-PapersOnLine, 56, 2, 8036, 8041, Elsevier BV, Jul. 2023, [Peer-reviewed], [Lead author]
English, International conference proceedings

Design of reduced-order and pinning controllers for probabilistic Boolean networks using reinforcement learning
Michiaki Takizawa, Koichi Kobayashi, Yuh Yamashita
Applied Mathematics and Computation, 457, 128211, 128211, Elsevier BV, Jul. 2023, [Peer-reviewed], [Last author]
English, Scientific journal

Multi-Agent Reinforcement Learning Based on Event-Based Communication　　　　　　　　　　　　　　　
Hiroki Sunai, Koichi Kobayashi, Yuh Yamashita
Proc. of the 38th International Technical Conference on Circuits/Systems, Computers, and Communications, Jun. 2023, [Last author]
English, International conference proceedings

Notion of Opacity and Its Verification for Discrete-Time Piecewise Linear Systems　　　　　　　　　　　　　　　
Taiga Matsumae, Koichi Kobayashi, Yuh Yamashita
Proc. of the 38th International Technical Conference on Circuits/Systems, Computers, and Communications, Jun. 2023, [Peer-reviewed], [Last author]
English, International conference proceedings

Fixed Point Preserving Model Reduction of Boolean Networks Focusing on Complement and Absorption Laws
Fuma Motoyama, Koichi Kobayashi, Yuh Yamashita
IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences, E106-A, 5, 721, 728, May 2023, [Peer-reviewed], [Last author]
English, Scientific journal

Detection of False Data Injection Attacks in Distributed State Estimation of Power Networks
Sho Obata, Koichi Kobayashi, Yuh Yamashita
IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences, E106-A, 5, 729, 735, Institute of Electronics, Information and Communications Engineers (IEICE), May 2023, [Peer-reviewed], [Last author]
English, Scientific journal

Block sparse design of distributed controllers for dynamical network systems
Ryosuke Adachi, Yuh Yamashita, Koichi Kobayashi
International Journal of Robust and Nonlinear Control, 33, 1, 49, 66, 10 Jan. 2023, [Peer-reviewed]
English, Scientific journal

Asymptotic stabilization with group‐wise sparse input based on control Lyapunov function approach
Yuh Yamashita, Kiminori Sakano, Koichi Kobayashi
International Journal of Robust and Nonlinear Control, 33, 1, 35, 48, Wiley, 10 Jan. 2023, [Peer-reviewed], [Lead author, Corresponding author]
English, Scientific journal

Passivity‐based control of nonlinear active dynamic vibration absorber
Sheng Hao, Yuh Yamashita, Koichi Kobayashi
International Journal of Robust and Nonlinear Control, 33, 5, 3247, 3266, Wiley, 06 Jan. 2023, [Peer-reviewed]
English, Scientific journal

Decentralized Event-Triggered Output Feedback Control for Cyber-Physical Systems　　　　　　　　　　　　　　　
Koichi Kitamura, Koichi Kobayashi, Yuh Yamashita
Proc. of the Joint Symposium of AROB 28th 2023, ISBC 8th 2023, and SWARM 6th 2023, Jan. 2023, [Peer-reviewed], [Last author]
English, International conference proceedings

LMI-Based Design of Structured Sparse Output Feedback Controllers　　　　　　　　　　　　　　　
Yuta Kawano, Koichi Kobayashi, Yuh Yamashita
Proc. of the Joint Symposium of AROB 28th 2023, ISBC 8th 2023, and SWARM 6th 2023, Jan. 2023, [Peer-reviewed], [Last author]
English, International conference proceedings

Output Feedback Ultimate Boundedness Control with Decentralized Event-Triggering
Koichi KITAMURA, Koichi KOBAYASHI, Yuh YAMASHITA
IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences, Institute of Electronics, Information and Communications Engineers (IEICE), 2023, [Peer-reviewed], [Last author]
English, Scientific journal

Virtual merge and split at intersection for vehicle platooning based on self-triggered pinning consensus control
Ayaka Tanaka, Koichi Kobayashi, Yuh Yamashita
Advanced Robotics, 37, 1, 1, 10, Informa UK Limited, Jan. 2023, [Peer-reviewed], [Last author]
English, Scientific journal

Output Feedback Ultimate Boundedness Control with Decentralized Event-Triggering　　　　　　　　　　　　　　　
Koichi Kitamura, Koichi Kobayashi, Yuh Yamashita
Proc. of 2022 International Symposium on Nonlinear Theory and Its Applications, Dec. 2022, [Peer-reviewed], [Last author]
English, International conference proceedings

Blockchain-Based Optimization of Distributed Energy Management Systems with Real-Time Demand Response
Daiki OGAWA, Koichi KOBAYASHI, Yuh YAMASHITA
IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences, E105-A, 11, 1478, 1485, Institute of Electronics, Information and Communications Engineers (IEICE), Nov. 2022, [Peer-reviewed], [Last author]
English, Scientific journal

On Initial Locations, Feasibility, and Performance in Multi-Agent Surveillance Systems　　　　　　　　　　　　　　　
Kyohei Murakata, Koichi Kobayashi, Yuh Yamashita
Proc. of 2022 IEEE 11th Global Conference on Consumer Electronics (GCCE), Oct. 2022, [Peer-reviewed], [Last author]
English, International conference proceedings

Control of Multi-Agent Surveillance Systems Using Reinforcement Learning　　　　　　　　　　　　　　　
Keita Terashima, Koichi Kobayashi, Yuh Yamashita
Proc. of the SICE Annual Conference 2022, ThB05.4, Sep. 2022, [Peer-reviewed], [Last author]
English, International conference proceedings

Online Optimization of Pickup and Delivery Problem with Fuel Constraints　　　　　　　　　　　　　　　
Ryo Matsuoka, Koichi Kobayashi, Yuh Yamashita
Proc. of the International Technical Conference on Circuits/Systems, Computers, and Communications 2022, Jul. 2022, [Peer-reviewed], [Last author]
English, International conference proceedings

Sensor Scheduling-Based Detection of False Data Injection Attacks in Power System State Estimation
Sho OBATA, Koichi KOBAYASHI, Yuh YAMASHITA
IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences, E105-A, 6, 1015, 1019, Institute of Electronics, Information and Communications Engineers (IEICE), Jun. 2022, [Peer-reviewed], [Last author]
English, Scientific journal

LMI-Based Design of Output Feedback Controllers with Decentralized Event-Triggering
Koichi KITAMURA, Koichi KOBAYASHI, Yuh YAMASHITA
IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences, E105-A, 5, 816, 822, Institute of Electronics, Information and Communications Engineers (IEICE), May 2022, [Peer-reviewed], [Last author]
English, Scientific journal

Self-Triggered Consensus Approach to Vehicle Platooning at Intersection　　　　　　　　　　　　　　　
Ayaka Tanaka, Koichi Kobayashi, Yuh Yamashita
Proc. of IEEE 40th International Conference on Consumer Electronics, Jan. 2022, [Peer-reviewed], [Last author]
English, International conference proceedings

Robust passivity‐based control design for active nonlinear suspension system
Sheng Hao, Yuh Yamashita, Koichi Kobayashi
International Journal of Robust and Nonlinear Control, 32, 1, 373, 392, Wiley, Jan. 2022, [Peer-reviewed]
English, Scientific journal

Asymptotic stabilization of nonlinear systems with convex-polytope input constraints by continuous input
Yuh Yamashita, Ryosuke Matsukizono, Koichi Kobayashi
Automatica, 138, 110032, 110032, Elsevier BV, Nov. 2021, [Peer-reviewed], [Lead author]
English, Scientific journal

Distributed Optimal Estimation with Scalable Communication Cost
Ryosuke Adachi, Yuh Yamashita, Koichi Kobayashi
IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences, E104-A, 11, 1470, 1476, Institute of Electronics, Information and Communications Engineers (IEICE), Nov. 2021, [Peer-reviewed]
English, Scientific journal

On Detection of False Data Injection Attacks in Distributed State Estimation of Power Networks
Sho Obata, Koichi Kobayashi, Yuh Yamashita
2021 IEEE 10th Global Conference on Consumer Electronics (GCCE), 472, 473, IEEE, 12 Oct. 2021, [Peer-reviewed], [Last author]
English, International conference proceedings

A Graph-Theoretic Approach to Model Reduction of Boolean Networks　　　　　　　　　　　　　　　
Motoyama, Fuma, Kobayashi, Koichi, Yamashita, Yuh
Proc. of the SICE Annual Conference 2021, 952, 955, Sep. 2021, [Peer-reviewed]
English, International conference proceedings

Pinning Stabilization of Probabilistic Boolean Networks Using Reinforcement Learning　　　　　　　　　　　　　　　
Takizawa, Michiaki, Kobayashi, Koichi, Yamashita, Yuh
Proc. of the SICE Annual Conference 2021, 942, 945, Sep. 2021, [Peer-reviewed]
English, International conference proceedings

Optimal Control Considering Standby Power of Actuators　　　　　　　　　　　　　　　
Kunitsugu, Yohei, Yamashita, Yuh, Kobayashi, Koichi
Proc. of the SICE Annual Conference 2021, 467, 470, Sep. 2021, [Peer-reviewed]
English, International conference proceedings

LMI-Based Design of Decentralized Event-Triggered Control Over Sensor and Actuator Networks　　　　　　　　　　　　　　　
Kitamura, Koichi, Kobayashi, Koichi, Yamashita, Yuh
Proc. of the SICE Annual Conference 2021, 457, 460, Sep. 2021, [Peer-reviewed]
English, International conference proceedings

Construction of ISS Lyapunov functions for Hamiltonian systems with multiple disturbances
Sheng Hao, Yuh Yamashita, Koichi Kobayashi
IFAC-PapersOnLine (Special Issue for Proceedings of 3rd IFAC Conference on Modelling, Identification and Control of Nonlinear Systems), 54, 14, 281, 286, Elsevier BV, Sep. 2021, [Peer-reviewed]
English, International conference proceedings

Decentralized Event-Triggered Control of Discrete-Time Linear Systems via Output Feedback
Koichi Kitamura, Koichi Kobayashi, Yuh Yamashita
IEEE International Symposium on Industrial Electronics, 2021-, Institute of Electrical and Electronics Engineers Inc., 20 Jun. 2021
English, International conference proceedings

Distributed Observer Design on Sensor Networks with Random Communication
Yuh Yamashita, Haruka Sumita, Ryosuke Adachi, Koichi Kobayashi
IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences, E104-A, 3, 613, 621, Mar. 2021, [Peer-reviewed], [Lead author]
English, Scientific journal

Uniformly Ultimate Boundedness Control with Decentralized Event-Triggering
Koichi Kobayashi, Kyohei Nakajima, Yuh Yamashita
IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences, E104-A, 2, 455, 461, Feb. 2021, [Peer-reviewed], [Last author]
English, Scientific journal

Effectiveness and Limitation of Blockchain in Distributed Optimization: Applications to Energy Management Systems
Daiki Ogawa, Koichi Kobayashi, Yuh Yamashita
IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences, E104-A, 2, 423, 429, Institute of Electronics, Information and Communications Engineers (IEICE), Feb. 2021, [Peer-reviewed], [Last author]
English, Scientific journal

Sensor Scheduling-Based Detection of False Data Injection Attacks in Power System State Estimation
Sho Obata, Koichi Kobayashi, Yuh Yamashita
Digest of Technical Papers - IEEE International Conference on Consumer Electronics, 2021-, Institute of Electrical and Electronics Engineers Inc., 10 Jan. 2021
English, International conference proceedings

Distributed estimation based on weighted data aggregation over delayed sensor networks
Ryosuke Adachi, Yuh Yamashita, Koichi Kobayashi
IFAC Journal of Systems and Control, 14, 100109, 100109, Elsevier BV, Dec. 2020, [Peer-reviewed], [International Magazine]
English, Scientific journal

Design of global smooth implicit control Lyapunov function for multiple-integrator system with input constraint
Yuh Yamashita, Naoto Adachi, Ryo Nonaka, Koichi Kobayashi
Systems & Control Letters, 145, 104776, 104776, Elsevier BV, Nov. 2020, [Peer-reviewed], [Lead author, Corresponding author], [International Magazine]
English, Scientific journal

Blockchain-Based Optimization of Energy Management Systems with Demand Response
Daiki Ogawa, Koichi Kobayashi, Yuh Yamashita
Proc. of the IEEE 9th Global Conference on Consumer Electronics, 58, 59, Institute of Electronics, Information and Communications Engineers (IEICE), Oct. 2020, [Peer-reviewed], [Last author]
English, International conference proceedings

Stochastic Model Predictive Control of Energy Management Systems with Human in the Loop
Shogo Shimamoto, Koichi Kobayashi, Yuh Yamashita
Proc. of the IEEE 9th Global Conference on Consumer Electronics, 60, 61, Oct. 2020, [Peer-reviewed], [Last author]
English, International conference proceedings

Active Vibration Control of Nonlinear 2DOF Mechanical Systems via IDA-PBC
Sheng Hao, Yuh Yamashita, Koichi Kobayashi
IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences, E103.A, 9, 1078, 1085, Institute of Electronics, Information and Communications Engineers (IEICE), 01 Sep. 2020, [Peer-reviewed]
English, Scientific journal

On Attack Detection in Sensor Networks Using Distributed Moving Horizon Estimation　　　　　　　　　　　　　　　
Kei Isono, Koichi Kobayashi, Yuh Yamashita
Proc. of the SICE Annual Conference 2020, 1602, 1605, Sep. 2020, [Peer-reviewed], [Last author]
English, International conference proceedings

LMI-Based Simultaneous Design of Controllers and Decentralized Event-Triggering Conditions　　　　　　　　　　　　　　　
Koichi Kobayashi, Kyohei Nakajima, Yuh Yamashita
Proc. of the SICE Annual Conference 2020, 1585, 1588, Sep. 2020, [Peer-reviewed], [Last author]
English, International conference proceedings

Enforcing Security of Power System State Estimation Using Random Sensor Scheduling　　　　　　　　　　　　　　　
Sho Obata, Koichi Kobayashi, Yuh Yamashita
Proc. of the SICE Annual Conference 2020, 1163, 1165, Sep. 2020, [Peer-reviewed], [Last author]
English, International conference proceedings

ADMM-Based Optimization of Distributed Energy Management Systems with Demand Response　　　　　　　　　　　　　　　
Daiki Ogawa, Koichi Kobayashi, Yuh Yamashita
Proc. of the 21st IFAC World Congress, Jul. 2020, [Peer-reviewed], [Last author]
English, International conference proceedings

On Sensor Attack Detection in Control Systems Using Moving Horizon Estimation and Control Performance　　　　　　　　　　　　　　　
Kei Isono, Koichi Kobayashi, Ryosuke Adachi, Yuh Yamashita
Proc. of the 21st IFAC World Congress, Jul. 2020, [Peer-reviewed], [Last author]
English, International conference proceedings

On Minimum Time Control for Dynamical Transportation Using ADMM　　　　　　　　　　　　　　　
Ryosuke Adachi, Yuh Yamashita, Koichi Kobayashi
Proc. of the 21st IFAC World Congress, Jul. 2020, [Peer-reviewed]
English, International conference proceedings

Optimal Regulators for Nonlinear Systems with Incompatible State and Input Cost Functions
Yuh Yamashita, Yuta Sakai, Koichi Kobayashi
IFAC-PapersOnLine (Special issue of 21st IFAC World Congress), 53, 2, 6819, 6824, Elsevier BV, Jul. 2020, [Peer-reviewed], [Lead author, Corresponding author]
English, International conference proceedings

Passivity-Based Nonlinear Active Suspension Control Utilizing Relative Information
Sheng Hao, Yuh Yamashita, Koichi Kobayashi
IFAC-PapersOnLine (Special issue of 21st IFAC World Congress), 53, 2, 5586, 5591, Elsevier BV, Jul. 2020, [Peer-reviewed]
English, International conference proceedings

Design of Controller and Observer for Dynamical Network Systems Based on Weighted Degrees
Ryosuke Adachi, Yuh Yamashita, Koichi Kobayashi
IFAC-PapersOnLine (Special issue of 21st IFAC World Congress), 53, 2, 3330, 3335, Elsevier BV, Jul. 2020, [Peer-reviewed]
English, International conference proceedings

Model Reduction of Boolean Networks Using BDD　　　　　　　　　　　　　　　
Fuma Motoyama, Koichi Kobayashi, Yuh Yamashita
Proc. of the 35th International Technical Conference on Circuits/Systems, Computers and Communications, 89, 93, Jul. 2020, [Peer-reviewed], [Last author]
English, International conference proceedings

Model Predictive Control of Energy Management Systems with Human Decision Making　　　　　　　　　　　　　　　
Shogo Shimamoto, Koichi Kobayashi, Yuh Yamashita
Proc. of the 35th International Technical Conference on Circuits/Systems, Computers and Communications, 84, 88, Jul. 2020, [Peer-reviewed], [Last author]
English, International conference proceedings

Distributed Observer over Delayed Sensor Networks for Systems with Unknown Inputs
ADACHI Ryosuke, YAMASHITA Yuh, KOBAYASHI Koichi
IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences, E103-A, 2, 469, 477, The Institute of Electronics, Information and Communication Engineers, Feb. 2020, [Peer-reviewed]
English, Scientific journal,

In this paper, we consider the design problem of an unknown-input observer for distributed network systems under the existence of communication delays. In the proposed method, each node estimates all states and calculates inputs from its own estimate. It is assumed that the controller of each node is given by an observer-based controller. When calculating each node, the input values of the other nodes cannot be utilized. Therefore, each node calculates alternative inputs instead of the unknown inputs of the other nodes. The alternative inputs are generated by own estimate based on the feedback controller of the other nodes given by the assumption. Each node utilizes these values instead of the unknown inputs when calculating the estimation and delay compensation. The stability of the estimation error of the proposed observer is proven by a Lyapunov-Krasovskii functional. The stability condition is given by a linear matrix inequality (LMI). Finally, the result of a numerical simulation is shown to verify the effectiveness of the proposed method.

Dynamic Surveillance by Multiple Agents with Fuel Constraints
Ryo Masuda, Koichi Kobayashi, Yuh Yamashita
IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences, E103-A, 2, 462, 468, Feb. 2020, [Peer-reviewed]
English, Scientific journal

Self-Triggered Pinning Consensus Control for Multi-Agent Systems
Shun Andoh, Koichi Kobayashi, Yuh Yamashita
IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences, E103.A, 2, 443, 450, Institute of Electronics, Information and Communications Engineers (IEICE), 01 Feb. 2020, [Peer-reviewed], [Last author]
English, Scientific journal

Hierarchical Pinning Control for Consensus of Multi-Agent Systems and Its Application to Vehicle Platooning
Shun Andoh, Koichi Kobayashi, Yuh Yamashita
Proceedings of 2020 IEEE/SICE International Symposium on System Integration, 1064, 1069, Jan. 2020, [Peer-reviewed]
English, International conference proceedings

Robust Active Vibration Controller Design for a Class of Underactuated Nonlinear Systems
Sheng Hao, Yuh Yamashita, Koichi Kobayashi
Proceedings of 2020 IEEE/SICE International Symposium on System Integration, 465, 470, Jan. 2020, [Peer-reviewed]
English, International conference proceedings

Construction Method of Probabilistic Boolean Networks Based on Imperfect Information
Katsuaki Umiji, Koichi Kobayashi, Yuh Yamashita
Algorithms, 12, 12, 268 (9 pages), Dec. 2019, [Peer-reviewed]
English, Scientific journal

Dynamic Surveillance by Multiple Agents with Fuel Constraints
Yuh YamashitaRyo Masuda, Koichi Kobayashi, Yuh Yamashita
Proc. of the 2019 IEEE International Conference on Systems, Man, and Cybernetics, 3351, 3356, Oct. 2019, [Peer-reviewed]
English, International conference proceedings

Stabilization of Nonlinear Systems by Sparse Input with Input Grouping　　　　　　　　　　　　　　　
Kiminori Sakano, Yuh Yamashita, Koichi Kobayashi
Proceedings of SICE Annual Conference 2019, 1653, 1656, Sep. 2019, [Peer-reviewed]
English, International conference proceedings

Observer-Based Self-Triggered Pinning Control for Consensus of Multi-Agent Systems　　　　　　　　　　　　　　　
Yuh YamashitaShun Andoh, Koichi Kobayashi, Yuh Yamashita
Proceedings of SICE Annual Conference 2019, 1440, 1443, Sep. 2019, [Peer-reviewed]
English, International conference proceedings

On the Optimality of Distributed Observer Using Belief Propagation　　　　　　　　　　　　　　　
Ryosuke Adachi, Yuh Yamashita, Koichi Kobayashi
Proceedings of SICE Annual Conference 2019, 645, 648, Sep. 2019, [Peer-reviewed]
English, International conference proceedings

Control of Bilateral Teleoperation System Consisting of Heterogeneous Manipulators with Communication Delay
Akihisa Higashino, Yuh Yamashita, Koichi Kobayashi
IFAC PapersOnline (Part of special issue: 11th IFAC Symposium on Nonlinear Control Systems), 52, 16, 747, 752, Sep. 2019, [Peer-reviewed]
English, International conference proceedings

Design and Value Evaluation of Demand Response Based on Model Predictive Control
Kodai Miyazaki, Koichi Kobayashi, Shun-Ichi Azuma, Nobuyuki Yamaguchi, Yuh Yamashita
IEEE Transactions on Industrial Informatics, 15, 8, 4809, 4818, Aug. 2019, [Peer-reviewed]
English, Scientific journal

Decentralized Event-Triggered Control of Discrete-Time Linear Systems Based on Uniformly Ultimate Boundedness
Koichi Kobayashi, Kyohei Nakajima, Yuh Yamashita
Proceedings of the 2019 Asian Control Conference, 1392, 1397, Jun. 2019, [Peer-reviewed]
English, International conference proceedings

Distributed Estimation Over Delayed Sensor Networks with Cyclic Structure
Ryosuke Adachi, Yuh Yamashita, Koichi Kobayashi
Proceedings of the 2019 Asian Control Conference, 1386, 1391, Jun. 2019, [Peer-reviewed]
English, International conference proceedings

Attack Detection in Control Systems Based on Unknown Input Observers and Control Performance　　　　　　　　　　　　　　　
Kei Isono, Koichi Kobayashi, Ryosuke Adachi, Yuh Yamashita
Proc. of the 34th International Technical Conference on Circuits/Systems, Computers and Communications, 290, 293, Jun. 2019, [Peer-reviewed]
English, International conference proceedings

Effectiveness and Limitation of Blockchain in Distributed Optimization　　　　　　　　　　　　　　　
Daiki Ogawa, Koichi Kobayashi, Yuh Yamashita
Proc. of the 34th International Technical Conference on Circuits/Systems, Computers and Communications, 286, 289, Jun. 2019, [Peer-reviewed]
English, International conference proceedings

Blockchain-Based Distributed Optimization for Energy Management Systems
Daiki Ogawa, Koichi Kobayashi, Yuh Yamashita
Proceedings of 2019 IEEE International Conference on Industrial Cyber Physical Systems, 706, 711, May 2019, [Peer-reviewed]
English, International conference proceedings

Distributed Estimation over Delayed Sensor Network with Scalable Communication
Ryosuke Adachi, Yuh Yamashita, Koichi Kobayashi
IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences, E102-A, 5, 712, 720, May 2019, [Peer-reviewed]
English, Scientific journal

Computationally Efficient Model Predictive Control for Multi-Agent Surveillance Systems
Koichi Kobayashi, Mifuyu Kido, Yuh Yamashita
IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences, E102-A, 2, 372, 378, Feb. 2019, [Peer-reviewed]
English, Scientific journal

Convergence Rates of Stochastic Homogeneous Systems
Kenta Hoshino, Yuki Nishimura, Yuh Yamashita
Systems & Control Letters, 124, 33, 39, Feb. 2019, [Peer-reviewed]
English, Scientific journal

Asymptotic stabilization of nonholonomic four-wheeled vehicle with steering limitation
Wataru Hashimoto, Yuh Yamashita, Koichi Kobayashi
IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences, E102-A, 1, 227, 234, Jan. 2019, [Peer-reviewed]
English, Scientific journal

Active Nonlinear Tuned Mass Damper via IDA-PBC
Sheng Hao, Yuh Yamashita, Koichi Kobayashi
Proc. of 2018 IEEE International Conference on Systems, Man, and Cybernetics, 4383, 4388, Oct. 2018, [Peer-reviewed]
English, International conference proceedings

Computationally Efficient Model Predictive Control for Multi-Agent Surveillance Systems
Koichi Kobayashi, Mifuyu Kido, Yuh Yamashita
Proc. of 2018 IEEE International Conference on Systems, Man, and Cybernetics, 2015, 2020, Oct. 2018, [Peer-reviewed]
English, International conference proceedings

Observer Design for Distributed Network Systems with Communication Delays
Ryosuke Adachi, Yuh Yamashita, Koichi Kobayashi
IFAC PapersOnline; Proceedings of the 5th IFAC Conference on Analysis and Control of Chaotic Systems, 51, 33, 115, 125, Oct. 2018, [Peer-reviewed]
English, International conference proceedings

Switching Controller Design for Quantized Event-Triggered Control　　　　　　　　　　　　　　　
Shumpei Yoshikawa, Koichi Kobayashi, Yuh Yamashita
Proceedings of the SICE Annual Conference 2018, 1797, 1800, Sep. 2018, [Peer-reviewed]
English, International conference proceedings

Self-Triggered Predictive Pinning Control for Consensus of Multi-Agent Systems　　　　　　　　　　　　　　　
Shun Andoh, Koichi Kobayashi, Yuh Yamashita
Proceedings of the SICE Annual Conference 2018, 1806, 1809, Sep. 2018, [Peer-reviewed]
English, International conference proceedings

Asymptotically Stabilizing Controller Generating Sparse Input for Nonlinear Systems
Yuh Yamashita, Kiminori Sakano, Koichi Kobayashi
Proc. of the 23rd International Symposium on Mathematical Theory of Networks and Systems, 435, 440, Jul. 2018, [Peer-reviewed]
English, International conference proceedings

MPC-Based Design of Demand Response Programs in Energy Management Systems　　　　　　　　　　　　　　　
Kodai Miyazaki, Koichi Kobayashi, Shun-ichi Azuma, Nobuyuki Yamaguchi, Yuh Yamashita
Proc. of the 33rd International Technical Conference on Circuits/Systems, Computers and Communications, Jul. 2018, [Peer-reviewed]
English, International conference proceedings

Vibration Suppression of Hamiltonian Systems with Velocity and Force Disturbances Using IDA-PBC
Sheng Hao, Yuh Yamashita, Koichi Kobayashi
IFAC Papers Online, Proc. of the Second IFAC Conference on Modelling, Identification and Control of Nonlinear Systems, 51, 13, 285, 290, Jun. 2018, [Peer-reviewed]
English, International conference proceedings

MPC-based Co-design of Control and Routing for Wireless Sensor and Actuator Networks
Dai Satoh, Koichi Kobayashi, Yuh Yamashita
International Journal of Control, Automation and Systems, 16, 3, 953, 960, Institute of Control, Robotics and Systems, 01 Jun. 2018, [Peer-reviewed]
English, Scientific journal

Optimal Monitoring of Multiple Agents via Time Sequence-Based Modeling
Ryo MASUDA, Koichi KOBAYASHI, Yuh YAMASHITA
SICE Journal of Control, Measurement, and System Integration, 11, 3, 169, 173, May 2018, [Peer-reviewed]
English, Scientific journal

Delay-compensated maximum-likelihood-estimation method and its application for quadrotor UAVs
Ryosuke Adachi, Yuh Yamashita
IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences, E101A, 4, 678, 684, Institute of Electronics, Information and Communication, Engineers, IEICE, 01 Apr. 2018, [Peer-reviewed]
English, Scientific journal

Nonlinear system identification by affine coordinate unification of locally identified MIMO linear systems
Kazuya Nomura, Yuh Yamashita, Koichi Kobayashi
Proc. of the SICE International Symposium on Control Systems 2018, 220, 225, Mar. 2018, [Peer-reviewed]
English, International conference proceedings

Quantized event-triggered control of discrete-time linear systems with switching triggering conditions
Shumpei Yoshikawa, Koichi Kobayashi, Yuh Yamashita
IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences, E101A, 2, 322, 327, Institute of Electronics, Information and Communication, Engineers, IEICE, 01 Feb. 2018, [Peer-reviewed]
English, Scientific journal

Markov Chain-Based Modeling Techniques of Appliances for Demand Response　　　　　　　　　　　　　　　
Kenta Ohashi, Koichi Kobayashi, Yuh Yamashita
Proc. of the 23rd International Symposium on Artificial Life and Robotics, 805, 808, Jan. 2018, [Peer-reviewed]
English, International conference proceedings

Model Predictive-Based Demand Response in Energy Management Systems　　　　　　　　　　　　　　　
Yuh YamashitaKodai Miyazaki, Koichi Kobayashi, Shun-ichi Azuma, Nobuyuki Yamaguchi, Yuh Yamashita
Proc. of the 23rd International Symposium on Artificial Life and Robotics, 815, 818, Jan. 2018, [Peer-reviewed]
English, International conference proceedings

BMI approach to design of networked control systems with decentralized event-triggering
Kyohei Nakajima, Koichi Kobayashi, Yuh Yamashita
IEEE Workshop on Signal Processing Advances in Wireless Communications, SPAWC, 2017-, 1, 5, Institute of Electrical and Electronics Engineers Inc., 19 Dec. 2017, [Peer-reviewed]
English, International conference proceedings

Asymptotic Stabilization of Nonholonomic Four-Wheeled Vehicle with Hysteresis Mechanism
Wataru Hashimoto, Yuh Yamashita, Koichi Kobayashi
Proceedings of the 2017 International Symposium on Nonlinear Theory and Its Applications, 30, 33, Dec. 2017, [Peer-reviewed]
English, International conference proceedings

A unification method of locally identified linear systems and reconstruction of nonlinear dynamical model
Kazuya Nomura, Yuh Yamashita, Koichi Kobayashi
IFAC-PapersOnLine, 50, 1, 14004, 14009, Elsevier B.V., 01 Jul. 2017, [Peer-reviewed]
English, Scientific journal

Data Aggregation based Estimation for Sensor Network with Communication Delay
Ryosuke Adachi, Yuh Yamashita, Koichi Kobayashi
IFAC-PapersOnLine, 50, 1, 2488, 2493, Elsevier B.V., 01 Jul. 2017, [Peer-reviewed]
English, Scientific journal

Asymptotic Stabilization of Nonlinear Systems with Convex-Polytope Input Constraints and its Inverse Optimality
Yuh Yamashita, Ryosuke Matsukizono, Koichi Kobayashi
IFAC-PapersOnLine, 50, 1, 1397, 1402, Elsevier B.V., 01 Jul. 2017, [Peer-reviewed]
English, Scientific journal

Switched Probabilistic Model of Consumers for Demand Response　　　　　　　　　　　　　　　
Kenta Ohashi, Koichi Kobayashi, Yuh Yamashita
Proceedings of the 32nd International Technical Conference on Circuits, Systems, Computers, and Communications, 143, 146, Jul. 2017, [Peer-reviewed]
English, International conference proceedings

Approximate MLD System Model of Switched Linear Systems for Model Predictive Control
Shin Kanazawa, Koichi Kobayashi, Yuh Yamashita
SICE Journal of Control, Measurement, and System Integration, 10, 3, 136, 140, May 2017, [Peer-reviewed]
English, Scientific journal

MPC-Based Surveillance over Graphs by Multiple Agents
Mifuyu Kido, Koichi Kobayashi, Yuh Yamashita
SICE Journal of Control, Measurement, and System Integration, 10, 3, 253, 258, May 2017, [Peer-reviewed]
English, Scientific journal

Linear Quadratic Regulator with Decentralized Event-Triggering
Kyohei Nakajima, Koichi Kobayashi, Yuh Yamashita
IEICE TRANSACTIONS ON FUNDAMENTALS OF ELECTRONICS COMMUNICATIONS AND COMPUTER SCIENCES, E100A, 2, 414, 420, Feb. 2017, [Peer-reviewed]
English, Scientific journal

Periodic Model Predictive Control of Multi-Hop Control Networks
Dai Satoh, Koichi Kobayashi, Yuh Yamashita
IEICE TRANSACTIONS ON FUNDAMENTALS OF ELECTRONICS COMMUNICATIONS AND COMPUTER SCIENCES, E100A, 2, 406, 413, Feb. 2017, [Peer-reviewed]
English, Scientific journal

Quantized Event-Triggered Control of Discrete-Time Linear Systems with Switching Triggering Conditions
Shumpei Yoshikawa, Koichi Kobayashi, Yuh Yamashita
2017 56TH ANNUAL CONFERENCE OF THE SOCIETY OF INSTRUMENT AND CONTROL ENGINEERS OF JAPAN (SICE), 313, 316, 2017, [Peer-reviewed]
English, International conference proceedings

Optimal Monitoring of Multiple Agents via Time Sequence-Based Modeling
Ryo Masuda, Koichi Kobayashi, Yuh Yamashita
2017 56TH ANNUAL CONFERENCE OF THE SOCIETY OF INSTRUMENT AND CONTROL ENGINEERS OF JAPAN (SICE), 168, 171, 2017, [Peer-reviewed]
English, International conference proceedings

Stochastic Model Predictive Control of Multi-Hop Control Networks with Packet Dropouts
Dai Satoh, Koichi Kobayashi, Yuh Yamashita
2017 56TH ANNUAL CONFERENCE OF THE SOCIETY OF INSTRUMENT AND CONTROL ENGINEERS OF JAPAN (SICE), 164, 167, 2017, [Peer-reviewed]
English, International conference proceedings

Potential Game on Measures and its Dynamical Behavior
Yuh Yamashita
2017 56TH ANNUAL CONFERENCE OF THE SOCIETY OF INSTRUMENT AND CONTROL ENGINEERS OF JAPAN (SICE), 209, 213, 2017, [Peer-reviewed]
English, International conference proceedings

Periodic Model Predictive Control of Multi-Hop Control Networks　　　　　　　　　　　　　　　
Dai Satoh, Koichi Kobayashi, Yuh Yamashita
Proceedings of the 2016 IEEE International Conference on Systems, Man, and Cybernetics, Oct. 2016, [Peer-reviewed]
English, International conference proceedings

Backstepping for Set-valued Upper Control Laws and Its Application to Control Allocation Problem
Daiki Suzuki, Yuh Yamashita, Koichi Kobayashi
Proceedings of the 2016 IEEE International Conference on Systems, Man, and Cybernetics, 29, 4, 175, 181, THE INSTITUTE OF SYSTEMS, CONTROL AND INFORMATION ENGINEERS (ISCIE), Oct. 2016, [Peer-reviewed]
English, International conference proceedings, This paper provides a new framework of control allocation of over-actuated system for static optimization of inputs via dynamical extension and potential approach. The static optimization of the control allocation is performed in real-time approximately, by varying the input according to the potential. To ensure asymptotic stability of the controlled system, we extends the backstepping method to our cases where more flexible additional potential can be used. Under the conditions on the set of the minimizer, the growth rate around the set, and the unimodality of the additional potential with some auxiliary assumptions, the extended potential function becomes a control Lyapunov function of the augmented system. The effectiveness of the proposed method is demonstrated by simulations.

Approximate MLD System Model of Switched Linear Systems for Model Predictive Control　　　　　　　　　　　　　　　
Shin Kanazawa, Koichi Kobayashi, Yuh Yamashita
Proceedings of the SICE Annual Conference 2016, 1745, 1748, Sep. 2016, [Peer-reviewed]
English, International conference proceedings

Model Predictive Control of Multiple Plants over Communication Networks　　　　　　　　　　　　　　　
Dai Satoh, Koichi Kobayashi, Yuh Yamashita
Proceedings of the SICE Annual Conference 2016, 1737, 1740, Sep. 2016, [Peer-reviewed]
English, International conference proceedings

Global Asymptotic Stabilization of Nonlinear Deterministic Systems Using Wiener Processes
Kenta Hoshino, Yuki Nishimura, Yuh Yamashita, Daisuke Tsubakino
IEEE TRANSACTIONS ON AUTOMATIC CONTROL, 61, 8, 2318, 2323, Aug. 2016, [Peer-reviewed]
English, Scientific journal

An MILP Approach to Optimal Surveillance over Graphs　　　　　　　　　　　　　　　
Mifuyu Kido, Koichi Kobayashi, Yuh Yamashita
Proc. of the 31st International Technical Conference on Circuits/Systems, Computers and Communications, 133, 136, 11 Jul. 2016, [Peer-reviewed]
English, International conference proceedings

Backstepping for set-valued upper control laws and its application to control allocation problem
Daiki Suzuki, Yuh Yamashita
Transactions of the Institute of Systems, Control and Information Engineers, 29, 4, 175, 181, THE INSTITUTE OF SYSTEMS, CONTROL AND INFORMATION ENGINEERS (ISCIE), Apr. 2016, [Peer-reviewed]
Japanese, Scientific journal, This paper provides a new framework of control allocation of over-actuated system for static optimization of inputs via dynamical extension and potential approach. The static optimization of the control allocation is performed in real-time approximately, by varying the input according to the potential. To ensure asymptotic stability of the controlled system, we extends the backstepping method to our cases where more flexible additional potential can be used. Under the conditions on the set of the minimizer, the growth rate around the set, and the unimodality of the additional potential with some auxiliary assumptions, the extended potential function becomes a control Lyapunov function of the augmented system. The effectiveness of the proposed method is demonstrated by simulations.

Linear Quadratic Regulator with Decentralized Event-Triggering
Kyohei Nakajima, Koichi Kobayashi, Yuh Yamashita
PROCEEDINGS OF THE IECON 2016 - 42ND ANNUAL CONFERENCE OF THE IEEE INDUSTRIAL ELECTRONICS SOCIETY, 5374, 5379, 2016, [Peer-reviewed]
English, International conference proceedings

Asymptotic Stabilization of Nonholonomic Four-Wheeled Vehicle with Steering Limitation based on Lyapunov Function Approach
W. Hashimoto, Y. Yamashita, R. Nonaka, K. Kobayashi
IFAC PAPERSONLINE, 49, 18, 235, 240, 2016, [Peer-reviewed]
English, International conference proceedings

Multiple obstacle avoidance of four-wheeled vehicle with steering limitation using nondifferentiable control Lyapunov function
Ryo Nonaka, Yuh Yamashita, Daisuke Tsubakino
ADVANCED ROBOTICS, 30, 1, 15, 28, Jan. 2016, [Peer-reviewed]
English, Scientific journal

Vibration suppression for mass-spring-damper systems with a tuned mass damper using interconnection and damping assignment passivity-based control
Takashi Aoki, Yuh Yamashita, Daisuke Tsubakino
INTERNATIONAL JOURNAL OF ROBUST AND NONLINEAR CONTROL, 26, 2, 235, 251, Jan. 2016, [Peer-reviewed]
English, Scientific journal

Continuous-time delayed feedback control for chaotic systems using complex number observer
Yuh Yamashita
IFAC-PapersOnLine, 28, 18, 199, 204, 01 Nov. 2015, [Peer-reviewed], [Lead author, Last author, Corresponding author]
English, International conference proceedings

Maximum Likelihood Estimation Method for Nonlinear System with Sensor Delay　　　　　　　　　　　　　　　
Ryosuke Adachi, Yuh Yamashita, Daisuke Tsubakino
Proceedings of SICE Annual Conference 2015, 626, 629, Jul. 2015
English, International conference proceedings

Static State Feedback Control System Design for PVTOL System via Minimum Projection Method
KUGA SOKI, SATO YASUYUKI, NAKAMURA HISAKAZU, YAMASHITA YU
Transactions of the Society of Instrument and Control Engineers, 51, 5, 361, 370, The Society of Instrument and Control Engineers, May 2015, [Peer-reviewed]
Japanese, Scientific journal, "Dynamic extension" is commonly used for stabilization of planar vertical takeoff and landing (PVTOL) system. Most of controllers designed by this method suffer from singularities of division-by-zero. We propose a "static" control Lyapunov function (CLF) design method for a PVTOL system by using a CLF obtained by dynamic extension and minimum projection method. Then, we design an inverse optimal controller with the designed static CLF. Moreover, we show that the proposed controller successfully stabilizes a desired operating point even in the neighborhood of the singularity where the conventional dynamic extension can not stabilize.

Asymptotic Stabilization of Two-Wheeled Mobile Robot via Locally Semiconcave Generalized Homogeneous Control Lyapunov Function
Shunsuke KIMURA, Hisakazu NAKAMURA, Yuh YAMASHITA
SICE Journal of Control, Measurement, and System Integration, 8, 2, 122, 130, The Society of Instrument and Control Engineers, Mar. 2015, [Peer-reviewed]
English, Scientific journal, A locally semiconcave control Lyapunov function exists for every globally asymptotically controllable system; however for nonholonomic systems, the issue of a locally semiconcave generalized homogeneous control Lyapunov function is not investigated. In this paper, the authors propose a locally semiconcave generalized homogeneous control Lyapunov function for Brockett integrator as a canonical form of nonholonomic systems. Moreover, the authors propose an exponentially stabilizing controller for a two-wheeled mobile robot with the function. The effectiveness of the proposed method are confirmed by computer simulation and an experiment, and advantages over previously proposed controllers are confirmed by experiments.

Stabilization of Artstein's Circle by Continuous Stochastic Feedback
Kenta Hoshino, Yuki Nishimura, Yuh Yamashita, Jun Yoneyama
2015 IEEE CONFERENCE ON CONTROL AND APPLICATIONS (CCA 2015), 257, 262, 2015, [Peer-reviewed]
English, International conference proceedings

Delay-Compensated Maximum Likelihood Estimation Method for Quadrotor UAV
Ryosuke Adachi, Yuh Yamashita
2015 IEEE CONFERENCE ON CONTROL AND APPLICATIONS (CCA 2015), 601, 606, 2015, [Peer-reviewed]
English, International conference proceedings

Higher-Order Sliding-Mode Control for Binary Input by Using Implicit Lyapunov Function
Ryo Nonaka, Yuh Yamashita, Daisuke Tsubakino
IFAC-PapersOnLine, 48, 11, 866, 871, Elsevier B.V., 2015, [Peer-reviewed]
English, Scientific journal

State estimation for boundary-coupled parabolic distributed parameter systems using spatial averages
Daisuke Tsubakino, Yuh Yamashita
2015 10TH ASIAN CONTROL CONFERENCE (ASCC), 2015, [Peer-reviewed]
English, International conference proceedings

General Scheme for Design of Higher-Order Sliding-Mode Controller
Ryo Nonaka, Yuh Yamashita, Daisuke Tsubakino
2015 AMERICAN CONTROL CONFERENCE (ACC), 5176, 5181, 2015, [Peer-reviewed]
English, International conference proceedings

Asymptotic stabilization of nonlinear systems on general manifolds via minimum projection method
Hisakazu Nakamura, Yuh Yamashita, Hirokazu Nishitani
2009 European Control Conference, ECC 2009, 2757, 2762, Institute of Electrical and Electronics Engineers Inc., 26 Mar. 2014
English, International conference proceedings

Discrete-Time Approximation under Zero-Order Holder and Its Application to Continuous-Time System Identification
Aoki Daisuke, Tsubakino Daisuke, Yamashita Yuh
Proceedings of the Japan Joint Automatic Control Conference, 57, 1412, 1415, The Japan Joint Automatic Control Conference, 2014
Japanese, 連続時間伝達関数から離散時間近似伝達関数を得る方法として，Tustin 変換を用いる方法が知られている．これは時間領域では，台形則による数値積分に対応し，入力が連続関数であれば離散時間近似として妥当なものである．しかしながら，現実よく用いられる零次ホールダを経由すると，入力が不連続関数となってしまう．そこで本研究では，入力の不連続性を考慮したさまざまな次数の離散時間近似式を導出する．さらに，離散時間近似式とその変換を用いた，間接的な連続時間システムの同定についても考察する．

Stability Preserving Model Reduction by Moment Matching for Hierarchical Systems
Minami Ryoichiro, Tsubakino Daisuke, Yamashita Yuh
Proceedings of the Japan Joint Automatic Control Conference, 57, 814, 817, The Japan Joint Automatic Control Conference, 2014
Japanese, 本稿では，階層構造をもつ線形システムに対して，安定性を考慮したモーメントマッチングによる低次元化法を考察する．モーメントマッチングでは，サブシステム毎に低次元化を行った場合に，システム全体のモーメントマッチングが達成できることが知られている．しかしながら，元のシステムの安定性が必ずしも保存されないという問題がある．そこで本研究では，サブシステムの低次元化モデルのL2ゲインを適切に設定することにより，低次元化システムの安定性を保証することを提案する．

Homogeneous Stabilization of Driftless Input-Affine Systems Using Wiener Processes
Kenta Hoshino, Yuh Yamashita, Yuki Nishimura, Daisuke Tsubakino
2014 IEEE 53RD ANNUAL CONFERENCE ON DECISION AND CONTROL (CDC), 3167, 3172, 2014, [Peer-reviewed]
English, International conference proceedings

Collision-free Formation Control of Two-wheeled Vehicles based on Triangular LQ Optimal Regulator
Takashi Kusunoki, Daisuke Tsubakino, Yuh Yamashita
2014 IEEE CONFERENCE ON CONTROL APPLICATIONS (CCA), 1072, 1077, 2014, [Peer-reviewed]
English, International conference proceedings

Boundary control of a cascade of two parabolic PDEs with different diffusion coefficients
Daisuke Tsubakino, Miroslav Krstic, Yuh Yamashita
Proc. 52nd IEEE Conf. Dec. & Cont., 3720, 3725, Dec. 2013, [Peer-reviewed]
English, International conference proceedings

Stochastic Asymptotic Stabilizers for Deterministic Input-Affine Systems Based on Stochastic Control Lyapunov Functions
Yuki Nishimura, Kanya Tanaka, Yuji Wakasa, Yuh Yamashita
IEICE TRANSACTIONS ON FUNDAMENTALS OF ELECTRONICS COMMUNICATIONS AND COMPUTER SCIENCES, E96A, 8, 1695, 1702, Aug. 2013, [Peer-reviewed]
English, Scientific journal

Boundary Control of Boundary Coupled Parabolic Distributed Parameter Systems based on Partial State Transformation
Daisuke Tsubakino, Kazuya Nomura, Yuh Yamashita
Transactions of the Institute of Systems, Control and Information Engineers, 26, 7, 277, 287, THE INSTITUTE OF SYSTEMS, CONTROL AND INFORMATION ENGINEERS (ISCIE), Jul. 2013, [Peer-reviewed]
Japanese, Scientific journal, This paper considers a boundary stabilization problem of systems described by boundary coupled two one-dimensional parabolic partial differential equations based on the backstepping method. Unlike the conventional backstepping framework, we propose a state transformation that contains the state of the unforced subsystem partially. It is proved that this transformation is well-defined and converts the original system into an exponentially stable system together with an associated state feedback control law under a condition that ensures the stability of the unforced subsystem. The original system with this control law inherits the stability of the transfomed one. The effectiveness of the obtained control law is demonstrated numerically.

Stochastic Extremum-Seeking Algorithm for One-Dimensional and Multivariate Static Systems
HOSHINO KENTA, YAMASHITA YUH
SICE J Control Meas Syst Integr, 6, 3, 177, 185, The Society of Instrument and Control Engineers, May 2013, [Peer-reviewed]
English, The aim of this paper is to present a stochastic extremum-seeking algorithm for one-dimensional and multivariate optimization of static systems. Extremum-seeking algorithms estimate the optimum value of a function using perturbation signals. The authors propose three schemes (a basic scheme, an annealing parameter scheme, and a high-pass filter scheme) for the one-parameter problem and one scheme (a high-pass filter scheme) for the multivariate problem. These methods employ Wiener processes for the perturbation signals. In this paper, the proposed methods are shown to converge by means of a stability analysis of stochastic systems. The paper presents some numerical examples to demonstrate the effectiveness of the methods.

Simultaneous estimation of vehicle sideslip angle and tire-road friction coefficient
Momoko Yoshida, Yuh Yamashita
2013 PROCEEDINGS OF SICE ANNUAL CONFERENCE (SICE), 1586, 1591, 2013, [Peer-reviewed]
English, International conference proceedings

Stability and Stabilization of Homogeneous Stochastic Systems
Kenta Hoshino, Yuh Yamashita, Yuki Nishimura, Daisuke Tsubakino
2013 IEEE 52ND ANNUAL CONFERENCE ON DECISION AND CONTROL (CDC), 1229, 1234, 2013, [Peer-reviewed]
English, International conference proceedings

Control of two-wheeled mobile robot via homogeneous semiconcave control Lyapunov function
Shunsuke Kimura, Hisakazu Nakamura, Yuh Yamashita
IFAC Proceedings Volumes (IFAC-PapersOnline), 9, 1, 92, 97, 2013, [Peer-reviewed]
English, International conference proceedings

Constructive design method of stochastic continuous feedback laws for stabilization of deterministic nonlinear systems
Kenta Hoshino, Yuki Nishimura, Yuh Yamashita, Daisuke Tsubakino
2013 AMERICAN CONTROL CONFERENCE (ACC), 2013 Vol.8, 6424, 6429, 2013, [Peer-reviewed]
English, International conference proceedings

Stochastic asymptotic stabilizers for deterministic input-affine systems based on stochastic control lyapunov functions
Yûki Nishimura, Kanya Tanaka, Yuji Wakasa, Yuh Yamashita
IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences, E96-A, 8, 1695, 1702, Institute of Electronics, Information and Communication, Engineers, IEICE, 2013, [Peer-reviewed]
English, Scientific journal

Stability and stabilization of homogeneous stochastic systems
Kenta Hoshino, Yuh Yamashita, Yûki Nishimura, Daisuke Tsubakino
Proceedings of the IEEE Conference on Decision and Control, 1229, 1234, Institute of Electrical and Electronics Engineers Inc., 2013, [Peer-reviewed]
English, International conference proceedings

Boundary control of a cascade of two parabolic PDEs with different diffusion coefficients
Daisuke Tsubakino, Miroslav Krstic, Yuh Yamashita
Proceedings of the IEEE Conference on Decision and Control, 3720, 3725, Institute of Electrical and Electronics Engineers Inc., 2013, [Peer-reviewed]
English, International conference proceedings

Digital Control with One Sampling Delay Focused on Value of Control Lyapunov Function of Continuous-time System
Shu Kusano, Yuh Yamashita
Transactions of the Society of Instrument and Control Engineers, 48, 12, 889, 897, 計測自動制御学会 ; [196-]-, Dec. 2012, [Peer-reviewed]
Japanese, Scientific journal

Numerical Computation of Families of Dissipative Boundaries for Two-Dimensional Gradient-Like Morse-Smale Dynamical Systems
Yukishige Izue, Ryuji Enomoto, Yuh Yamashita
IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences, J95-A, 3, 2011JAP1066, Mar. 2012, [Peer-reviewed]
Japanese, Scientific journal

Vibration suppression of mass-spring-damper system with dynamic dampers using IDA-PBC
Takashi Aoki, Yuh Yamashita, Daisuke Tsubakino
IFAC Proceedings Volumes (IFAC-PapersOnline), 45, 19, 42, 47, IFAC Secretariat, 2012, [Peer-reviewed]
English, International conference proceedings

Navigation Function of Mobile Robots for Formation Driving
Masahiro Yamada, Yuh Yamashita, Daisuke Tsubakino
2012 IEEE INTERNATIONAL CONFERENCE ON CONTROL APPLICATIONS (CCA), 1590, 1595, 2012, [Peer-reviewed]
English, International conference proceedings

Control Law for Multiple Obstacle Avoidance of Four-wheeled Vehicle with Limited Steering Angle by Multilayer Minimum Projection Method
Ryo Nonaka, Yuh Yamashita, Daisuke Tsubakino
2012 IEEE INTERNATIONAL CONFERENCE ON CONTROL APPLICATIONS (CCA), 1578, 1583, 2012, [Peer-reviewed]
English, International conference proceedings

A Search Algorithm for Control Lyapunov Functions Using Radial Basis Function Networks
Takayuki Tsuzuki, Taiki Yagi, Kazunobu Yoshida, Yuh Yamashita
Proceedings of SICE Annual Conference 2011, 390, 394, Sep. 2011, [Peer-reviewed]
English, International conference proceedings

Novel ODE-Type Smith Predictor for Nonlinear Control Systems with Delay
Xuanxuan TENG, Yuh YAMASHITA
SICE Journal of Control, Measurement, and System Integration, 4, 5, 380, 386, The Society of Instrument and Control Engineers, Sep. 2011, [Peer-reviewed]
English, Scientific journal, This paper proposes a novel ODE-type Smith predictor for nonlinear control systems with transmission delays. The presence of time delays in the transmission of the control signals and the sensor signals may severely affect the performance of the closed-loop system and prevent the successful application of established nonlinear control methodologies. First, we investigate a backstepping interpretation of Smith predictors for linear time-variant (LTV) systems in the state space. Second, we propose a new nonlinear Smith predictor, the error dynamics of which is locally stabilized by another Smith predictor for the LTV systems. The Smith predictor can reduce the computational cost of the controller, because integral equations, which should be solved at each time in previously proposed predictive controllers, are replaced by inner-product operations.

Schrodinger Equations Constructing Approximate Solutions to Infinite-Horizon Optimal Regulators
Yuki Nishimura, Kanya Tanaka, Yuji Wakasa, Yuh Yamashita
Transactions of the Japan Society for Industrial and Applied Mathematics, 21, 3, 197, 209, The Japan Society for Industrial and Applied Mathematics, Mar. 2011, [Peer-reviewed]
Japanese, Scientific journal, Pontryagin formalized optimal control problems as canonical systems, which are concepts from analytic mechanics. Recently, a canonical quantization method for optimal control problems was proposed. In this paper, we derive a sufficient condition that particular solutions to the canonical quantized optimal regulator problems converge to strict solutions to the original optimal control problems with infinite-time horizons. Further, we discuss possibility that the canonical quantization method yields useful approximate methods for nonlinear optimal regulator problems.

Static Nonsmooth Control Lyapunov Function Design via Dynamic Extension
Takahiro Yamazaki, Yuh Yamashita, Hisakazu Nakamura
2011 50TH IEEE CONFERENCE ON DECISION AND CONTROL AND EUROPEAN CONTROL CONFERENCE (CDC-ECC), 7573, 7578, 2011, [Peer-reviewed]
English, International conference proceedings

Schrödinger equations for constructing infinite time horizon optimal regulators
Yuki Nishimura, Kanya Tanaka, Yuji Wakasa, Yuh Yamashita
IFAC Proceedings Volumes (IFAC-PapersOnline), 18, 1, 8058, 8063, 2011, [Peer-reviewed]
English, International conference proceedings

Passivity based control of bilateral teleoperators with time delay using low-pass filters
Naoyoshi Ohkawa, Yuh Yamashita
IFAC Proceedings Volumes (IFAC-PapersOnline), 18, 1, 3274, 3279, 2011, [Peer-reviewed]
English, International conference proceedings

Novel extremum seeking algorithm using Wiener process
Kenta Hoshino, Yuh Yamashita
2011 19th Mediterranean Conference on Control and Automation, MED 2011, 886, 891, 2011, [Peer-reviewed]
English, International conference proceedings

Novel ODE-type nonlinear Smith predictor for networked control systems with time-varying delay
Xuanxuan Teng, Yuh Yamashita
2011 19th Mediterranean Conference on Control and Automation, MED 2011, 19, 24, 2011, [Peer-reviewed]
English, International conference proceedings

Global Asymptotic Stabilization for a Nonlinear System on a Manifold via a Dynamic Compensator
Takayuki TSUZUKI, Yuh YAMASHITA
Transactions of the Society of Instrument and Control Engineers, 46, 10, 598, 606, The Society of Instrument and Control Engineers, Oct. 2010, [Peer-reviewed]
Japanese, Scientific journal, The purpose of this paper is to solve a global asymptotic stabilization problem for a nonlinear control system on a manifold with a complete metric. As well known, a system on a noncontractible manifold is not globally asymptotically stabilizable via a continuous feedback law. This problem results from the existence of multiple singular points of such a controlled system. It is shown that if all singular points can be assigned to a subspace of the extended state space using a dynamic compensator and a continuous feedback except for at most one jump, then the augmented system becomes globally asymptotically stable. Moreover, a method for stabilization is developed using a dynamic compensator and a global control Lyapunov function for an input-affine system. Finally, we propose a method for constructing the control Lyapunov function for a system such that the dimension of the coefficient matrix of the input is equal to the dimension of the state.

A sufficient condition for local semiconcavity of value function of nonlinear optimal regulator
Takayuki Tsuzuki, Yuh Yamashita
Proceedings of SICE Annual Conference 2010, 1559, 1562, Aug. 2010, [Peer-reviewed]
English, International conference proceedings

Observer-Based Delayed Feedback Control Stabilizing Unstable Periodic Orbits of Continuous-Time Chaotic Systems
Yuh Yamashita
Proceeding of IFAC Workshop on Periodic Control Systems 2010, 75, 80, Aug. 2010, [Peer-reviewed]
English, International conference proceedings

Numerical Computation of Regular Dissipative Boundaries for Two-Dimensional Gradient-Like Morse-Smale Dynamical Systems
Yukishige Izue, Ryuji Enomoto, Yuh Yamashita
IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences, J93-A, 2, 119, 126, The Institute of Electronics, Information and Communication Engineers, Feb. 2010, [Peer-reviewed]
Japanese, Scientific journal, 本研究の目的は,大域コンパクトアトラクタをもつような任意の二次元こう配的Morse-Smale力学系に対して,Conleyの意味におけるリヤプノフ関数を構成するための有効な方法を見出すことである.最初にいくつかの特徴的な散逸境界(リヤプノフ関数の水準面の境界)を求め,それらを組み合わせてリヤプノフ関数を構成したい.本論文では,その第一ステップとして,チューブと呼ばれる概念を用いて散逸境界を数値的に算定するためのアルゴリズムを提案し,数値例を用いてその有効性を確認する.

Novel ODE-type Nonlinear Smith Predictor for Networked Control Systems
Xuanxuan Teng, Yuh Yamashita
2010 IEEE INTERNATIONAL CONFERENCE ON CONTROL APPLICATIONS, 1773, 1778, 2010, [Peer-reviewed]
English, International conference proceedings

Minimum Projection Method for nonsmooth control Lyapunov function design on general manifolds
Hisakazu Nakamura, Yuh Yamashita, Hirokazu Nishitani
SYSTEMS & CONTROL LETTERS, 58, 10-11, 716, 723, Oct. 2009, [Peer-reviewed]
English, Scientific journal

Homogeneous Stabilization for Input Affine Homogeneous Systems
Nami Nakamura, Hisakazu Nakamura, Yuh Yamashita, Hirokazu Nishitani
IEEE TRANSACTIONS ON AUTOMATIC CONTROL, 54, 9, 2271, 2275, Sep. 2009, [Peer-reviewed]
English, Scientific journal

Asymptotic stabilization of nonlinear systems on general manifolds via minimum projection method
Hisakazu Nakamura, Yuh Yamashita, Hirokazu Nishitani
Proceedings of European Control Conference 2009, 2757, 2762, Aug. 2009, [Peer-reviewed]
English, Scientific journal

Construction Method of Approximate Stochastic Lyapunov Functions using Quantization of Markov Process
Yuki Nishimura, Yuh Yamashita
Transactions of the Institute of Systems, Control and Information Engineers, 22, 8, 295, 302, THE INSTITUTE OF SYSTEMS, CONTROL AND INFORMATION ENGINEERS (ISCIE), Aug. 2009, [Peer-reviewed]
Japanese, Scientific journal, The existence of stochastic Lyapunov functions assures that the systems are stable in probability. However, general scheme of obtaining stochastic Lyapunov functions has not been introduced yet. This paper extends the authors' previous method[21] obtaining Lyapunov functions for deterministic cases to stochastic cases. In the method, difference-approximation scheme[6,10] and quantization of Markov processes[1,14] are used to approximate Lyapunov equations by linear quantum-like equations. We propose a method of obtaining approximate stochastic Lyapunov functions for nonlinear stochastic systems by superimposing the eigenfunctions of the quantum-like equations.

Construction method of Lyapunov functions based on eigen analysis
Yuki Nishimura, Yuh Yamashita, Kanya Tanaka, Yuji Wakasa
Proceedings of 2009 ICCAS-SICE, 691, 694, Aug. 2009, [Peer-reviewed]
English, International conference proceedings

Stabilization Problems of Nonlinear Systems using Feedback laws with Wiener Processes
Yuki Nishimura, Kazuki Takehara, Yuh Yamashita, Kanya Tanaka, Yuji Wakasa
PROCEEDINGS OF THE 48TH IEEE CONFERENCE ON DECISION AND CONTROL, 2009 HELD JOINTLY WITH THE 2009 28TH CHINESE CONTROL CONFERENCE (CDC/CCC 2009), 7363, 7368, 2009, [Peer-reviewed]
English, International conference proceedings

Homogeneous stabilization for input affine homogeneous systems
Nami Nakamura, Hisakazu Nakamura, Yuh Yamashita
IEEE Transactions on Automatic Control, 54, 9, 2271, 2275, 2009, [Peer-reviewed]
English, Scientific journal

Global Asymptotical Stabilization of Morse-Smale Systems Using Weak Control-Lyapunov Functions
Gou NISHIDA, Takayuki TSUZUKI, Hisakazu NAKAMURA, Yuh YAMASHITA
SICE Journal of Control, Measurement, and System Integration, 2, 1, 43, 49, The Society of Instrument and Control Engineers, Jan. 2009, [Peer-reviewed]
English, Scientific journal, This paper proposes a method of constructing weak control-Lyapunov functions for nonlinear systems by introducing a topological geometric assumption called a Morse-Smale system. A Lyapunov function is one of the most important tools to study stability and stabilization of nonlinear systems. However, a general way of finding Lyapunov functions has not been found yet. First, we confirm there is a weak Lyapunov function for Morse-Smale systems. Next, we define the escapability for singular structures of the weak Lyapunov function. If all singular structures are escapable, then the Morse-Smale system is a globally asymptotically stabilizable one. Finally, we present the method of constructing a set of weak control-Lyapunov functions to achieve global stabilization. The method is described in terms of a recursive sequence of singular structures. We call the sequence a weak Lyapunov filtration.

Stabilization problems of nonlinear systems using feedback laws with wiener processes
Yuki Nishimura, Kazuki Takehara, Yuh Yamashita, Kanya Tanaka, Yuji Wakasa
Proceedings of the IEEE Conference on Decision and Control, 7363, 7368, 2009, [Peer-reviewed]
English, International conference proceedings

Stochastic Lyapunov Function Design using Quantization of Markov Process
Proceedings of 47th IEEE Conference on Decision and Control, 3475, 3480, 2008

Stabilization of nonlinear systems using weak-control-Lyapunov functions
NISHIDA G.
Proc. the 17th IFAC World Congress, Seoul, 2008, 6190, 6195, 2008

Global asymptotic stabilization for a nonlinear system on a manifold via a dynamic compensator　　　　　　　　　　　　　　　
Proceedings of 17th IFAC World Congress, 6178, 6183, 2008

Lyapunov Function Design using Quantization of Markov Process
Yuki Nishimura, Yuh Yamashita
IFAC Proceedings Volumes, 41, 2, 2808, 2813, Elsevier BV, 2008
English, International conference proceedings

Construction of Lyapunov Function Using Quantization of Markov Process
Yuki NISHIMURA, Yuh YAMASHITA
Transactions of the Society of Instrument and Control Engineers, 44, 1, 26, 35, 2008, [Peer-reviewed]
Japanese, Scientific journal

Inverse optimal control for nonlinear systems with input constraints
Nami Nakamura, Hisakazu Nakamura, Yuh Yamashita, Hirokazu Nishitani
Proceedings of 2007 European Control Conference, 5376, 5382, Jul. 2007, [Peer-reviewed]
English, International conference proceedings

Seeking Control Lyapunov-Morse Functions Using Genetic Programming for Global Asymptotical Stabilization of Nonlinear Systems
Takayuki TSUZUKI, Kousuke KUWADA, Yuh YAMASHITA
Transactions of the Society of Instrument and Control Engineers, 43, 2, 85, 92, 計測自動制御学会, Feb. 2007, [Peer-reviewed]
Japanese, Scientific journal

Homogeneous eigenvalue analysis for complex homogeneous systems
Nami Nakamura, Hisakazu Nakamura, Yuh Yamashita, Hirokazu Nishitani
IFAC Proceedings Volumes (IFAC-PapersOnline), 7, 1, 107, 112, IFAC Secretariat, 2007
English, International conference proceedings

Homogeneous stabilization for input-affine homogeneous systems
Nami Nakamura, Hisakazu Nakamura, Yuh Yamashita
PROCEEDINGS OF THE 46TH IEEE CONFERENCE ON DECISION AND CONTROL, VOLS 1-14, 3770, +, 2007, [Peer-reviewed]
English, International conference proceedings

State Feedback Stabilization for Distributed Parameter Systems of Parabolic Type with Adaptive Observers
OHMURO Akira, YAMASHITA Yuh, SHIMA Masasuke
Transactions of the Society of Instrument and Control Engineers, 43, 10, 901, 908, The Society of Instrument and Control Engineers, 2007
This paper proposes a design method of stabilizing state feedback for distributed parameter systems of parabolic type with adaptive observers. The distributed parameter system with unknown coefficients is described by evolution equations in Hilbert space. The structure of adaptive observer using filtered values generated from input and output is stated. Moreover, control law using estimates of unknown coefficients is derived. Finally, by assuming the persistency of excitation, stability of the proposed control system is shown.

Optimal control of formation flight based on MLD systems
Miao Du, Yuh Yamashita
PROCEEDINGS OF THE 2007 IEEE CONFERENCE ON CONTROL APPLICATIONS, VOLS 1-3, 1292, 1297, 2007, [Peer-reviewed]
English, International conference proceedings

Homogeneous eigenvalue analysis for complex homogeneous systems of degree (l,l)
Nami Nakamura, Hisakazu Nakamura, Yuh Yamashita, Hirokazu Nishitani
PROCEEDINGS OF SICE ANNUAL CONFERENCE, VOLS 1-8, 1238, +, 2007, [Peer-reviewed]
English, International conference proceedings

Global asymptotic stabilization of nonlinear system with multiple singular points using changeover of control Lyapunov-Morse function
Kazuki Takeharai, Takayuki Tsuzuki, Yuh Yamashita
PROCEEDINGS OF SICE ANNUAL CONFERENCE, VOLS 1-8, 104, +, 2007, [Peer-reviewed]
English, International conference proceedings

Homogeneous eigenvalue analysis for complex homegeneous systems　　　　　　　　　　　　　　　
7th IFAC Symposium on Nonlinear Control Systems, 415, 420, 2007

Semi-global output regulation of nonminimum-phase nonlinear systems via error feedback
Yoshinori Hirose, Yuh Yamashita
PROCEEDINGS OF SICE ANNUAL CONFERENCE, VOLS 1-8, 1259, +, 2007, [Peer-reviewed]
English, International conference proceedings

Homogeneous stabilization for input-affine homogeneous systems
Nami Nakamura, Hisakazu Nakamura, Yuh Yamashita
Proceedings of the IEEE Conference on Decision and Control, 80, 85, 2007, [Peer-reviewed]
English, International conference proceedings

On characteristic families of dissipative boundaries for two-dimensional gradient-like Morse-Smale controlled systems
Ryuji Enomoto, Yukishige Izue, Yuh Yamashita
2007 INTERNATIONAL CONFERENCE ON CONTROL, AUTOMATION AND SYSTEMS, VOLS 1-6, 1487, +, 2007, [Peer-reviewed]
English, International conference proceedings

Searching for control Lyapunov-Morse functions using genetic programming for global asymptotic stabilization of nonlinear systems
Takayuki Tsuzuki, Kousuke Kuwada, Yuh Yamashita
Proceedings of the 45th IEEE Conference on Decision and Control, 5114, 5119, Dec. 2006, [Peer-reviewed]
English, International conference proceedings

Asymptotic Stability Analysis for Homogeneous Systems Using Homogeneous Eigenvalues
Hisakazu Nakamura, Yuh Yamashita, Hirokazu Nishitani
Proceedings of the 45th IEEE Conference on Decision and Control, 4230, 4235, IEEE, Dec. 2006, [Peer-reviewed]
English, International conference proceedings

Adaptive Observers of Distributed Parameter Systems of Parabolic Type
Akira OHMURO, Yuh YAMASHITA, Masasuke SHIMA
Transactions of the Society of Instrument and Control Engineers, 42, 10, 1100, 1106, The Society of Instrument and Control Engineers, Oct. 2006, [Peer-reviewed]
Japanese, Scientific journal, This paper proposes a design method of adaptive observers for distributed parameter systems of parabolic type. For a distributed parameter system with unknown coefficients described by an evolution equation in Hilbert space, transformations of the state derives an input-output representation with filtered values. An adaptive law and a state observer are obtained, where the convergence of parameter error is evaluated by using the Lyapunov function. Under the assumption of persistency of excitation, parameter-error convergence to zero is guaranteed.

Stability Analysis of Homgoeneous Systems via Homogeneous Eigenvalues
Hisakazu NAKAMURA, Yuh YAMASHITA, Hirokazu NISHITANI
Transactions of the Society of Instrument and Control Engineers, 42, 8, 894, 901, The Society of Instrument and Control Engineers, Aug. 2006, [Peer-reviewed]
Japanese, Scientific journal, This paper focuses on the problem of stability of homogeneous systems with dilation. First, we propose 'homogeneous eigenvalue' for the homogeneous systems. Next, we analyze stability of the homogeneous systems using the homogeneous eigenvalues, and we show that the positive homogeneous eigenvalues imply instability. Finally, we show effectiveness of the proposed method by examples.

Existence of Homogeneous Eigenvalues for Homogeneous Systems
Hisakazu Nakamura, Yuh Yamashita, Hirokazu Nishitani
Proc. MTNS 2006, 2799, 2804, Jul. 2006, [Peer-reviewed]
English, International conference proceedings

Stabilization Problem of 1-Input Underactuated Mechanics　　　　　　　　　　　　　　　
Yuki Nishimura, Yuh Yamashita
17th International Symposium on Mathematical Theory of Networks and Systems, 1018, 1023, Jul. 2006, [Peer-reviewed]
English, International conference proceedings

Global Asymptotic Stabilization of Multi-Input Affine Systems by Using Control Lyapunov-Morse Function　　　　　　　　　　　　　　　
Takayuki Tsuzuki, Yuh Yamashita
17th International Symposium on Mathematical Theory of Networks and Systems, 22, 26, Jul. 2006, [Peer-reviewed]
English, International conference proceedings

Adaptive Observers of Distributed Parameter Systems of the Parabolic Type with Unknown Parameters　　　　　　　　　　　　　　　
Akira Ohmuro, Yuh Yamashita
17th International Symposium on Mathematical Theory of Networks and Systems, 2053, 2058, Jul. 2006, [Peer-reviewed]
English, International conference proceedings

Numerical Computation of Dissipative Boundaries for Two-Dimensional Gradient-Like Morse-Smale Dynamical Systems　　　　　　　　　　　　　　　
Yukishige Izue, Ryuji Enomoto, Yuh Yamashita
17th International Symposium on Mathematical Theory of Networks and Systems, 2043, 2047, Jul. 2006, [Peer-reviewed]
English, International conference proceedings

Postural Stability Analysis of Compass-like Biped Robot Model
Yuji Hosokawa, Hisakazu Nakamura, Hirokazu Nishitani, Yuh Yamashita
Journal of the Robotics Society of Japan, 24, 2, 232, 239, The Robotics Society of Japan, Feb. 2006, [Peer-reviewed]
Japanese, Scientific journal, This paper focuses on the problem of postural stability of a biped robot. We consider a compass-like biped model and analyze its postural stability based on the energy dissipation when the idling leg collides against the ground surface. We calculate the amount of energy dissipation by using rigid dynamics. We propose a novel criterion PSC (Postural Stability Criterion) that judges postural stability of the robot. Finally the effectiveness of the proposed criterion with two other indexes is demonstrated by computer simulation.

Stabilization of nonlinear planer systems using homogeneous eigenvalues
Hisakazu Nakamura, Gou Nishida, Hirokazu Nishitani, Yuh Yamashita
2006 SICE-ICASE INTERNATIONAL JOINT CONFERENCE, VOLS 1-13, 33, +, 2006
English, International conference proceedings

Global Asymptotic Stabilization by Using Control Lyapunov-Morse Functions
Takayuki TSUZUKI, Yuh YAMASHITA
Transactions of the Society of Instrument and Control Engineers, 42, 6, 643, 650, The Society of Instrument and Control Engineers, 2006
Japanese, Scientific journal, The purpose of this paper is to solve the global asymptotic stabilization problem for nonlinear systems on general manifolds. It is known that if the state space of a control system is not contractible, the system is not globally asymptotically stabilizable via C¹ feedback law, because gradient-like flow on the non-contractible manifold demands multiple singular points. In this paper, we define a control Lyapunov-Morse function having multiple critical points using the concept of the Lyapunov-Morse function, which is a kind of complete Lyapunov functions for dynamical systems with multiple isolated singular points. We derive a discontinuous feedback law from the control Lyapunov-Morse function. Moreover, a condition for global asymptotic stability of the controlled system with the discontinuous feedback law is also obtained.

Inverse Optimal Control for a Nonlinear System with an Input Constraint
Nami KIDANE, Hisakazu NAKAMURA, Yuh YAMASHITA, Hirokazu NISHITANI
Transactions of the Society of Instrument and Control Engineers, 42, 1, 26, 34, The Society of Instrument and Control Engineers, Jan. 2006, [Peer-reviewed]
Japanese, Scientific journal

Global finite-time control of wheeled mobile robots using homogeneous finite-time controllers
Nakamura Hisakazu, Yamashita Yuh, Nishitani Hirokazu
Proceedings of the Annual Conference of the Institute of Systems, Control and Information Engineers, 6, 231, 231, The Institute of Systems, Control and Information Engineers, 2006
In this paper, we propose a global finite-time stabilizer for a wheeled mobile robot.Moreover, we analyze the oscillation of the controlled system using homogeneous eigenvalue analysis.Finally, we confirm the effectiveness of the proposed method by computer simulation.

On the option pricing using stock prices and volatilities via time series analysis
KIMOTO TAKAMORI, OHMURO AKIRA, YAMASHITA YUH
Proceedings of the Annual Conference of the Institute of Systems, Control and Information Engineers, 6, 46, 46, The Institute of Systems, Control and Information Engineers, 2006
確率的なダイナミカルシステムで表現される株価の変動モデルに対しては、今日まで時系列解析やオプション理論など、さまざまな研究がなされてきたが、それらを組み合わせたオプションプライシングなどの研究は、あまり行われていないのが現状である。そこで、時系列解析により得られる推定値のオプションプライシングへの適用を試みる。そのために、ARモデルとSVモデルによる株価の時系列解析と、Edgeworth展開により近似される確率密度関数を用いたオプションモデルの導出を行う。

Asymptotic stability of homogeneous systems using homogeneous eigenvalues
Hisakazu Nakamura, Yuh Yamashita, Hirokazu Nishitani
PROCEEDINGS OF THE 45TH IEEE CONFERENCE ON DECISION AND CONTROL, VOLS 1-14, 4234, +, 2006, [Peer-reviewed]
English, International conference proceedings

Complex homogeneous eigenvalues for complex homogeneous systems　　　　　　　　　　　　　　　
Hisakazu Nakamura, Yuh Yamashita, Hirokazu Nishitani
Proc. of SICE Annual Conference 2005, 3033, 3036, Aug. 2005, [Peer-reviewed]
English, International conference proceedings

GLOBAL ASYMPTOTIC STABILIZATION BY USING THE CONTROL LYAPUNOV FUNCTION
Takayuki Tsuzuki, Yuh Yamashita, Ryuji Enomoto
IFAC Proceedings Volumes (Proc. IFAC World Congress 2005), 38, 1, 640, 645, Elsevier BV, Jul. 2005, [Peer-reviewed]
English, International conference proceedings

On a topological condition for strongly asymptotically stable differential inclusions
Yuh Yamashita, Takayuki Tsuzuki, Hisakazu Nakamura
2005 44th IEEE Conference on Decision and Control & European Control Conference, Vols 1-8, 5444, 5449, 2005, [Peer-reviewed]
English, International conference proceedings

Grobal position and posture control of a two-wheeled mobile robot using a discontinuous homogeneous control
H Nakamura, T Kaji, H Nishitani, Y Yamashita
2005 IEEE INTERNATIONAL CONFERENCE ON CONTROL APPLICATIONS (CCA), VOLS 1AND 2, 1569, 1574, 2005
English, International conference proceedings

Controller for a nonlinear system with an input constraint by using a control Lyapunov function I　　　　　　　　　　　　　　　
16th IFAC World Congress (CD-ROM), Th-E03-TO/4, 2005

Nonlinear continuous-time reference governors for constrained nonlinear systems　　　　　　　　　　　　　　　
16th IFAC World Congress (CD-ROM), Fr-M08-TO/6, 2005

Controller for a nonlinear system with an input constraint by using a control Lyapunov function II　　　　　　　　　　　　　　　
16th IFAC World Congress (CD-ROM), Th-E03-TO/5, 2005

Controller Design for a Nonlinear System with an Input Constraint
KIDANE Nami, NAKAMURA Hisakazu, YAMASHITA Yuh, NISHITANI Hirokazu
計測自動制御学会論文集, 41, 3, 250, 258, 計測自動制御学会, 2005
Japanese

Homogeneous eigenvalue analysis of homogeneous systems
NAKAMURA H.
16th IFAC World Congress, 2005, Mo-A11-TO/4, 2005

Thinking State Estimation using Multiple Physiological Signals
Taketoshi KUROOKA, Masato ANDO, Ippei HOSHI, Yuh YAMASHITA, Hirokazu NISHITANI
The Human Factors in Japan, 9, 2, 114, 122, 日本プラント・ヒューマンファクター学会, Jan. 2005, [Peer-reviewed]
Japanese, Scientific journal

Globally Asymptotically Stable Attitude Control System of Satellite Using Nonlinear Observer
YAMASHITA Yuh, NAKAMURA Hisakazu, NISHITANI Hirokazu
計測自動制御学会論文集, 40, 11, 1071, 1077, 計測自動制御学会, 30 Nov. 2004
Japanese

Lyapunov functions for homogeneous differential inclusions
Hisakazu Nakamura, Yuh Yamashita, Hirokazu Nishitani
IFAC Proceedings Volumes (Part of special issue: 6th IFAC Symposium on Nonlinear Control Systems), 37, 13, 733, 738, Elsevier BV, Sep. 2004, [Peer-reviewed]
English, International conference proceedings

Human modeling and simulation for plant operations
YH Jin, Y Yamashita, H Nishitani
COMPUTERS & CHEMICAL ENGINEERING, 28, 10, 1967, 1980, Sep. 2004
English, Scientific journal

Computer aids for knowledge management in plant operations
O Orapimpan, A Kurosaki, T Kurooka, Y Yamashita, H Nishitani
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH, 43, 14, 3731, 3740, Jul. 2004
English, Scientific journal

認知情報処理モデルを用いた異常診断におけるプラントオペレータの認知エラーの考察
金 銀花, 山下 裕, 西谷 紘一
ヒューマンファクターズ, 9, 1, 27, 37, 日本プラント・ヒューマンファクター学会, Jul. 2004
Japanese

Controller design for a nonlinear system with inputs restricted to a direct product of Minkowski balls
N Kidane, H Nakamura, Y Yamashita, H Nishitani
2004 43RD IEEE CONFERENCE ON DECISION AND CONTROL (CDC), VOLS 1-5, 4069, 4074, 2004
English, International conference proceedings

Inverse optimization for a nonlinear system with an input constraint
N Kidane, Y Yamashita, H Nakamura, H Nishitani
SICE 2004 ANNUAL CONFERENCE, VOLS 1-3, 1210, 1213, 2004
English, International conference proceedings

Stabilization of a cascade-connected nonlinear system with an input constraint　　　　　　　　　　　　　　　
6th IFAC Symposium on Nonlinear Control Systems, 341, 346, 2004

A Kansei design system for keyboard switch reaction forces using neural networks　　　　　　　　　　　　　　　
2nd International Conference on Artificial Intelligence in Engineering and Technology, 318, 321, 2004

Stabilization of a cascade-connected nonlinear system with an input constraint
H Nakamura, N Kidane, Y Yamashita, H Nishitani
SICE 2004 ANNUAL CONFERENCE, VOLS 1-3, 1874, 1879, 2004
English, International conference proceedings

Observer-based Controller Design for Nonlinear DAE Systems
KIDANE Nami, YAMASHITA Yuh, NISHITANI Hirokazu
Transactions of the Society of Instrument and Control Engineers, Vol. 40, No. 7, 721, 728, The Society of Instrument and Control Engineers, 2004
In this paper, we propose a design method of an observer-based controller for nonlinear differential algebraic equation (DAE) systems. We transform a DAE system to an explicit ordinary differential equation (ODE) system that is restricted to an invariant manifold by differentiating the original DAE repeatedly. If the DAE is non-regular, we add integrators to inputs to avoid impulse modes. We design a state feedback law that incorporates redundant state variables and an observer that estimates all of these variables simultaneously. We also give a set of sufficient conditions for the global stability of the control system. The efficiency of the controller is demonstrated by computer simulation.

Developing a driving simulator and an assessment methodology to estimate a driver's mental state when distracted
Hiroaki Kosaka, Akira Kurosaki, Atsushi Harada, Yuh Yamashita, Hirokazu Nishitani
SAE Technical Papers, Paper Number: 2004-01-0233, 2004
English, International conference proceedings

Compensation of transmission delay and packet-loss in nonlinear remote-control system　　　　　　　　　　　　　　　
The 10th IFAC/IFORS/IMACS/IFIP Symposium on Large Scale Systems: Theory and Applications, 627, 632, 2004

Modeling and Simulation of Plant Operator’s Fault Diagnosis Process
Yinhua JIN, Yuh YAMASHITA, Hirokazu NISHITANI
The Journal of the Society for Industrial Plant Human Factors of Japan, 8, 2, 68, 76, 日本プラント・ヒュ-マンファクタ-学会, Jan. 2004, [Peer-reviewed]
Japanese, Scientific journal

Controller design for a nonlinear system with inputs restricted to a direct product of Minkowski balls
Nami Kidane, Hisakazu Nakamura, Yuh Yamashita, Hirokazu Nishitani
Proceedings of the IEEE Conference on Decision and Control, 4, 4069, 4074, Institute of Electrical and Electronics Engineers Inc., 2004
English, International conference proceedings

Homogeneous Finite-Time Control of Chained Systems
NAKAMURA Hisakazu, YAMASHITA Yuh, NISHITANI Hirokazu
Transactions of the Society of Instrument and Control Engineers, 39, 8, 717, 725, The Society of Instrument and Control Engineers, 2003
This paper focuses on the problem of stabilization of a chained-form nonholonomic system. We propose a time-invariant discontinuous finite-time homogeneous controller for the chained system. The controller has no singular point where the control inputs become infinite values. Using the characteristics of the homogeneous system, we can select the convergence speed of the controlled system. Namely, we can choose an exponentially stable system or a finite-time stable system. We designed the controller for a 3-state chained system and confirmed the superior performance of the controlled system by computer simulations.

Finite-time stabilization of the high-order chained system
H Nakamura, Y Yamashita, H Nishitani
PROCEEDINGS OF THE 2003 AMERICAN CONTROL CONFERENCE, VOLS 1-6, 4137, 4142, 2003
English, International conference proceedings

Lyapunov Functions for Homogeneous Differential Inclusions
NAKAMURA Hisakazu, YAMASHITA Yuh, NISHITANI Hirokazu
計測自動制御学会論文集, 39, 4, 365, 374, 計測自動制御学会, 2003
Japanese

Observer Based I/O-linearizing Control of High Index DAE Systems　　　　　　　　　　　　　　　
2003 American Control Conference Proceedings, 3537, 3541, 2003

Support systems for knowledge inheritance from video images of plant operations
O Orapimpan, T Kurooka, Y Yamashita, H Nishitani
PROCESS SYSTEMS ENGINEERING 2003, PTS A AND B, 15, 1466, 1471, 2003
English, International conference proceedings

Observer design for nonlinear systems described by differential-algebraic equations
Y Yamashita, N Kidane, H Nishitani
PROCESS SYSTEMS ENGINEERING 2003, PTS A AND B, 15, 1100, 1105, 2003
English, International conference proceedings

Modeling and simulation of human errors in plant operations
YH Jin, T Kurooka, Y Yamashita, H Nishitani
PROCESS SYSTEMS ENGINEERING 2003, PTS A AND B, 15, 1280, 1285, 2003
English, International conference proceedings

心理状態を考慮したオペレータモデルの開発
金 銀花, 黒岡 武俊, 山下 裕
日本プラント・ヒュ-マンファクタ-学会誌, 7, 2, 86, 96, 日本プラント・ヒュ-マンファクタ-学会, Jan. 2003
Japanese

Discontinuous control of nonholonomic systems using nondifferentiable Lyapunov functions
H Nakamura, Y Yamashita, H Nishitani, H Yamamoto
SICE 2003 ANNUAL CONFERENCE, VOLS 1-3, 1415, 1418, 2003, [Peer-reviewed]
English, International conference proceedings

Stabilizability analysis and controller design for a nonlinear system with an input constraint
N Kidane, H Nakamura, Y Yamashita, H Nishitani
SICE 2003 ANNUAL CONFERENCE, VOLS 1-3, 1419, 1422, 2003, [Peer-reviewed]
English, International conference proceedings

A Cognitive Information Processing Model for Analysis of Plant Operator Errors　　　　　　　　　　　　　　　
Yinhua Jin, Taketoshi Kurooka, Yuh Yamashita, Hirokazu Nishitani
Proceedings of International Symposium on Design, Operation and Control of Chemical Processes, 313, 318, Dec. 2002, [Peer-reviewed]
English, International conference proceedings

Compensation for transmission delay and data loss in remote control systems　　　　　　　　　　　　　　　
Yuh Yamashita, Hirokazu Nishitani
Proceedings of International Symposium on Design, Operation and Control of Chemical Processes, 141, 146, Dec. 2002, [Peer-reviewed]
English, International conference proceedings

Support System for Emergency Training in Plant Operations　　　　　　　　　　　　　　　
Opat Orapimpan, Taketoshi Kurooka, Yuh Yamashita, Hirokazu Nishitani
Proceedings of International Symposium on Design, Operation and Control of Chemical Processes, 345, 350, Dec. 2002, [Peer-reviewed]
English, International conference proceedings

Thinking State Monitoring with Plural Physiological Signals　　　　　　　　　　　　　　　
Taketoshi Kurooka, Masato Ando, Yuh Yamashita, Hirokazu Nishitani
E International Conference on Systems, Man, and Cybernetics (CD-ROM), Paper ID: WP1N4, Oct. 2002, [Peer-reviewed]
English, International conference proceedings

Real-time Optimization Method for Nonlinear Receding-Horizon Control
IMAFUKU Kei, YAMASHITA Yuh, NISHITANI Hirokazu
JRSJ, 20, 7, 759, 770, The Robotics Society of Japan, Oct. 2002, [Peer-reviewed]
Japanese, Scientific journal, An optimal control problem for nonlinear systems is useful because various control objectives can be included in the cost function such as rapid stabilization and input cost minimization. However, there exist input restrictions of actuators and state constraints that arise from the movable region of the system in the real system. Therefore, the optimal control problem should be solved to satisfy these restrictions. In this paper, we propose a new method to realize nonlinear receding-horizon control under input restrictions and state constraints. First, a receding horizon control problem is formulated. Next, a new real-time optimization method is proposed. Then, the method is applied to solve a receding-horizon control problem of a wheeled vehicle. The effectiveness of the proposed method is shown through simulations and experimental results.

Stabilization of Nonholonomic Systems using Homogeneous Finite-time Control Technique　　　　　　　　　　　　　　　
Hisakazu Nakamura, Yuh Yamashita, Hirokazu Nisitani
15th World Congress of the IFAC, 2437, 2445, Jul. 2002, [Peer-reviewed]
English, International conference proceedings

シミュレータトレーニング収録ビデオからの知識の創出
Orapimpan Opat, 黒岡 武俊, 山下 裕
日本プラント・ヒュ-マンファクタ-学会誌, 7, 1, 10, 19, 日本プラント・ヒュ-マンファクタ-学会, Jul. 2002
Japanese

Tracking Control of Nonlinear Systems with No Relative Degree
YAMASHITA Yuh, ONISHI Norio, NISHITANI Hirokazu
Transactions of the Society of Instrument and Control Engineers, 38, 1, 18, 25, The Society of Instrument and Control Engineers, 31 Jan. 2002
Japanese, In this paper, we propose a new method of exact tracking control for multi-input multi-output nonlinear systems in which the relative degree for an output is not well defined at the origin. First, the system is transformed into a singularly perturbed system using a time-scale transformation and coordinate transformations. A composite control law is adopted to attain exact tracking control for the singularly perturbed system. However, it is difficult to solve simultaneous partial differential equations for the composite control law. We obtain an approximate solution of the PDEs via the ε-correction method. The proposed tracking control law is applied to the ball and plate system, which is a typical example having no relative degree at the origin.

Output regulation through singularities via state-feedback
Y Yamashita
NONLINEAR CONTROL SYSTEMS 2001, VOLS 1-3, 633, 638, 2002, [Peer-reviewed]
English, International conference proceedings

状態フィードバックを用いた非線形非最小位相系に対する大域的出力レギュレーション
大西 規雄, 山下 裕, 西谷 紘一
システム制御情報学会論文誌, 15, 1, 336, 343, Jan. 2002, [Peer-reviewed]
Japanese, Scientific journal

I/O-Linearizing controller and observer for Nonlinear DAE systems with high index
N Kidane, Y Yamashita, H Nishitani
SICE 2002: PROCEEDINGS OF THE 41ST SICE ANNUAL CONFERENCE, VOLS 1-5, 1966, 1969, 2002, [Peer-reviewed]
English, International conference proceedings

Smooth Lyapunov functions for homogeneous differential inclusions
H Nakamura, Y Yamashita, H Nishitani
SICE 2002: PROCEEDINGS OF THE 41ST SICE ANNUAL CONFERENCE, VOLS 1-5, 1974, 1979, 2002, [Peer-reviewed]
English, International conference proceedings

Compensation for transmission delay in remote-control system under measurement noise
Y Sawamura, Y Yamashita, H Nishitani
SICE 2002: PROCEEDINGS OF THE 41ST SICE ANNUAL CONFERENCE, VOLS 1-5, 219, 222, 2002, [Peer-reviewed]
English, International conference proceedings

Global asymptotic stabilization of nonminimum phase nonlinear systems via extended backstepping
N Onishi, Y Yamashita, H Nishitani
SICE 2002: PROCEEDINGS OF THE 41ST SICE ANNUAL CONFERENCE, VOLS 1-5, 2249, 2254, 2002, [Peer-reviewed]
English, International conference proceedings

Discontinuous finite-time control of multi-generator nonholonomic systems
H Nakamura, Y Yamashita, H Nishitani
SICE 2002: PROCEEDINGS OF THE 41ST SICE ANNUAL CONFERENCE, VOLS 1-5, 1980, 1983, 2002, [Peer-reviewed]
English, International conference proceedings

Computation Method for Optimal Control Problem with Terminal Constraints using Genetic Algorithm　　　　　　　　　　　　　　　
Yuh Yamashita, Masasuke Shima
Transactions of the Society of Instrument and Control Engineers, E-1, 274, 280, Dec. 2001, [Peer-reviewed]
English, Scientific journal

Real-time monitoring of a plant operator's thinking state
T Kurooka, M Yamakawa, Y Yamashita, H Nishitani
JOURNAL OF CHEMICAL ENGINEERING OF JAPAN, 34, 11, 1387, 1395, Nov. 2001, [Peer-reviewed]
English, Scientific journal

Acquiring and Representing Know-how and Know-why in On-site Plant Operations　　　　　　　　　　　　　　　
Opat Orapimpan, Taketoshi Kurooka, Yuh Yamashita, Hirokazu Nishitani
Proceedings of HCI International 2001, 239, 241, Aug. 2001, []

The Development of a Real-time Thinking State Monitoring System for Plant Operators　　　　　　　　　　　　　　　
Hirokazu Nishitani, Yuh Yamashita, Taketoshi Kurooka
Usability Evaluation and Interface Design: Cognitive Engineering, Intelligent Agents and Virtual Reality, 1, 1445, 1449, Aug. 2001, []

Condition Monitoring of a Heterogeneous Azeotropic Distillation Column Using Self-Organizing Maps　　　　　　　　　　　　　　　
Taketoshi Kurooka, Sadaharu Morishita, Yuh Yamashita, Hirokazu Nishitani
6th IFAC Symposium on Dynamics and Control of Process Systems, 585, 590, Jun. 2001, []

Development of a Learning System of Know-How and Know-Why in On-site Plant Operations
Opat Orapimpan, Kouichi Sakata, Taketoshi Kurooka, Yuh Yamashita, Hirokazu Nishitani
日本プラント・ヒューマンファクター学会誌, 6, 1, 33, 44, 日本プラント・ヒュ-マンファクタ-学会, Apr. 2001, []

A real-time thinking state monitoring system for plant operation
T Kurooka, M Yamakawa, Y Yamashita, H Nishitani
HUMAN-COMPUTER INTERACTION - INTERACT'01, 609, 616, 2001, []

Global output regulation of nonminimum phase nonlinear systems
N Onishi, Y Yamashita, H Nishitani
PROCEEDINGS OF THE 40TH IEEE CONFERENCE ON DECISION AND CONTROL, VOLS 1-5, 79, 84, 2001, []

I/O-Linearizing Controller with Observer for Nonlinear Systems Described by Differential-Algebraic Equations
YAMASHITA Yuh, NISHITANI Hirokazu, SHIMA Masasuke
計測自動制御学会論文集, 36, 12, 1101, 1107, 計測自動制御学会, 31 Dec. 2000

Numerical Methods for Viscosity Solutions of an Optimal Control Problem and an Obstacle Avoidance Problem for a Wheeled Vehicle
IMAFUKU Kei, YAMASHITA Yuh, NISHITANI Hirokazu
Transactions of the Institute of Systems, Control and Information Engineers, 44, 10, 458, 469, THE INSTITUTE OF SYSTEMS, CONTROL AND INFORMATION ENGINEERS (ISCIE), Oct. 2000, []
To construct an optimal regulator for a wheeled vehicle, we need a viscosity solution of the Hamilton-Jacobi partial differential equation (HJ-PDE). In this paper, we propose a new method to have the viscosity solution of the HJ-PDE more quickly by applying a new searching method which uses a sequence of random inputs. This method reduces the number of searching points and makes calculation time faster than the previous method. Next, we propose a method to have the viscosity solution for obstacle avoidance. From the theoretical result of optimal control with state constraints, we can get the viscosity solution which avoids obstacles optimally. Then we make sure that an optimal solution can be obtained analytically by the finite difference numerical approximation of the HJ-PDE. This new result gives us an optimal solution without searching. Finally, the effectiveness of control results calculated from proposed methods are confirmed through simulations.

視線分析を用いたプラントオペレータの挙動の分析
山本 純平, 黒岡 武俊, 山下 裕
日本プラント・ヒューマンファクター学会誌, 5, 2, 88, 98, 日本プラント・ヒューマンファクター学会, Oct. 2000

高速探索手法によるCSTRの自励振動反応を利用した収率のオンライン最適化
今福 啓, 山下 裕, 西谷 紘一
化学工学論文集, 26, 5, 683, 686, Sep. 2000, []

Design and verification of the SFC program for sequential Control
K Fujino, K Imafuku, Y Yamashita, H Nishitani
COMPUTERS & CHEMICAL ENGINEERING, 24, 2-7, 303, 308, Jul. 2000, []

Mind state estimation for operator support
T Kurooka, Y Yamashita, H Nishitani
COMPUTERS & CHEMICAL ENGINEERING, 24, 2-7, 551, 556, Jul. 2000, []

Dynamic simulation and nonlinear control system design of a heterogeneous azeotropic distillation column
T Kurooka, Y Yamashita, H Nishitani, Y Hashimoto, M Yoshida, M Numata
COMPUTERS & CHEMICAL ENGINEERING, 24, 2-7, 887, 892, Jul. 2000, []

Multivariable control of a distillation column by exact input-output linearization　　　　　　　　　　　　　　　
T. Kurooka, Y. Yamashita, H. Nishitani
Journal of Chemical Engineering of Japan, 33, 3, 406, 412, Jun. 2000

Mulitivariable Control of a Distillation Column by Exact Input-Output Linearization
Taketoshi Kurooka, Yuh Yamashita, Hirokazu Nishitani
Kagaku Kogaku Ronbunshu, 26, 3, 406, 412, 2000, []

Global output regulation through singularities
Y Yamashita, A Isidori
PROCEEDINGS OF THE 39TH IEEE CONFERENCE ON DECISION AND CONTROL, VOLS 1-5, 1295, 1300, 2000, []

Exact Input-Output Linearization Control of Heterogeneous Azeotropic Distillation Column　　　　　　　　　　　　　　　
Taketoshi Kurooka, Yuh Yamashita, Hirokazu Nishitani
1999 AIChE Annual Meeting (CD-ROM), Paper ID: 228i, Nov. 1999, []

Mind State Estimation in Logical Thinking Jobs
Taketoshi Kurooka, Yuh Yamashita, Hirokazu Nishitani
IEEE International Conference on Systems, Man, and Cybernetics, 407, 412, Oct. 1999, []

複数仕様を満たす制御系設計法の吸収冷凍機への応用
大形 明弘, 山下 裕, 西谷 紘一
化学工学論文集, 25, 5, 721, 727, Sep. 1999, []

Controller Design with Multiple Specifications for an Absorption Heat Pump System　　　　　　　　　　　　　　　
Akihiko Ohgata, Yuh Yamashita, Hirokazu Nishitani
The 8th Congress of Asian Pacific Confederation of Chemical Engineering, 599, 602, Aug. 1999, []

Measurement of Operator's Thinking State using EEGs　　　　　　　　　　　　　　　
Taketoshi Kurooka, Yuh Yamashita, Hirokazu Nishitani
The 8th Congress of Asian Pacific Confederation of Chemical Engineering, 1001, 1004, Aug. 1999, []

Control of a Wheeled Vehicle Using the Viscosity Solution of the Hamilton-Jacobi Partial Differential Equation
Kei Imafuku, Yuh Yamashita, Hirokazu Nishitani
Journal of the Robotics Society of Japan, 17, 5, 689, 695, The Robotics Society of Japan, Jul. 1999, []
To construct an optimal regulator for nonlinear systems, we need to solve a Hamilton-Jacobi partial differential equation (HJ-PDE) . However, if the system has nonholonomic constraints, the HJ-PDE has a nonsmooth solution because of the nonsmoothness of the optimal cost function. In such a case, the viscosity solution, a nonsmooth weak solution of the HJ-PDE, is obtained.
In this paper, we deal with a wheeled vehicle, which is a nonholonomic system, and propose a numerical method to achieve a viscosity solution of the HJ-PDE using the dynamic programming principle (DPP) . The DPP can be applied to acquire a nonsmooth solution of the HJ-PDE. We also construct an optimal control law using derivatives of the viscosity solution of the HJ-PDE. The effectiveness of the proposed method is shown through simulations.

Estimation of Plant Operator's Thinking State using EEGs
Taketoshi Kurooka, Yuh Yamashita, Hirokazu Nishitani
The 15th World Congress of International Measurement Confederation (CD-ROM), Paper ID: 18.2.3, 412, Jun. 1999, []

An Algorithm to Find a Static State Feedback Gain Matrix to Satisfy Multiple Specifications
OGATA Akihiro, YAMASHITA Yuh, NISHITANI Hirokazu
The Transactions of the Institute of Electrical Engineers of Japan. C, 119, 5, 615, 623, 電気学会, May 1999

Application of mind state estimation to plant operators
T Kurooka, M Kisa, Y Yamashita, H Nishitani
ANALYSIS, DESIGN AND EVALUATION OF MAN-MACHINE SYSTEMS 1998, 479, 484, 1999, []

On the Nonstandard Nonlinear H_∞ Control Problem
IMAFUKU Kei, YAMASHITA Yuh, SHINBA Takahiro, SHIMA Masasuke, NISHITANI Hirokazu
Transactions of the Society of Instrument and Control Engineers, 35, 1, 59, 65, The Society of Instrument and Control Engineers, Jan. 1999
Sufficient conditions of the nonstandard nonlinear H_∞ control problem are provided. This problem needs not to satisfy the rank condition of the direct-through matrices from the controlled input to the regulated output and from the disturbance to the measured output. First, we present a feedback law via state feedback. Next, a feedback law via output feedback and an observer gain are given. It is shown by extending the result of the linear system to the nonlinear system.

脳波を用いたプラントオペレ-タの思考状態推定
黒岡 武俊, 木佐 昌文, 山下 裕
日本プラント・ヒュ-マンファクタ-学会誌, 3, 2, 100, 109, 日本プラント・ヒュ-マンファクタ-学会, Oct. 1998

A New Method of Solving the Hamilton-Jacobi Partial Differential Equation
YAMASHITA Yuh, SHIMA Masasuke
Transactions of the Society of Instrument and Control Engineers, 34, 6, 571, 576, The Society of Instrument and Control Engineers, 30 Jun. 1998
A New method of solving the Hamilton-Jacobi partial differential equation is proposed. Hamilton-Jacobi partial differential equations are often used for solving nonlinear-H^∞-control problems or nonlinear-optimal-control problems. Some trajectories of the Hamiltonian system which is generated from the Hamiltonian function related to the Hamilton-Jacobi equation give a stable manifold of the system approximately, so they produce the derivative of the storage function. From their trajectories, the solution of the Hamilton-Jacobi equation is approximated with Bezier interpolation. The initial states of the trajectories are given by the linear system which approximates the dynamics on the stable manifold.

Control of Wheeled vehicle using dynamic programming principle　　　　　　　　　　　　　　　
Kei Imafuku, Yuh Yamashita, Hirokazu Nishitani
Mathematical Theory of networks and Systems, 1027, 1030, 1998, []

Controller Design of Absorption Heat Pump System via LMI
Akihiro Ohgata, Yuh Yamashita, Hirokazu Nishitani
Kagaku Kogaku Ronbunshu, 24, 2, 291, 298, 1998, []

Tracking control for unlinearizable nonlinear systems
Y Yamashita, T Bono, M Shima, H Nishitani
NONLINEAR CONTROL SYSTEMS DESIGN 1998, VOLS 1& 2, 195, 200, 1998, []

Numerical computational method using genetic algorithm for the optimal control problem with terminal constraints and free parameters
Y Yamashita, M Shima
NONLINEAR ANALYSIS-THEORY METHODS & APPLICATIONS, 30, 4, 2285, 2290, Dec. 1997, []

Invariance condition of general nonlinear control system with integral type output
M Shima, Y Yamashita
NONLINEAR ANALYSIS-THEORY METHODS & APPLICATIONS, 30, 4, 2279, 2284, Dec. 1997, []

プラント運転を行うオペレータモデルの開発
北島 禎二, 中山 慶彦, 黒岡 武俊, 山下 裕, 西谷 紘一
本プラント・ヒューマンファクター学会誌, 2, 2, 106, 115, 日本プラント・ヒュ-マンファクタ-学会, Oct. 1997, []

プラントオペレーションにおけるヒューマンモデリング
中山 慶彦, 北島 禎二, 山下 裕, 西谷 紘一
化学工学, 61, 8, 612, 613, 化学工学会, 05 Aug. 1997

On the Nonstandard Nonlinear H∞ Control Problem　　　　　　　　　　　　　　　
Yuh Yamashita, Takahiro Shinba, Masasuke Shima, Hirokazu Nishitani
Proc. of the 2nd Asian Control Conference, 579, 582, Jul. 1997, []

Computation Method for Optimal Control Problem with Terminal Constraints Using Genetic Algorithm
YAMASHITA Yuh, SHIMA Masasuke
Transactions of the Society of Instrument and Control Engineers, 33, 3, 189, 194, The Society of Instrument and Control Engineers, 31 Mar. 1997
In this paper, a new numerical computation method using genetic algorithm for an optimal control problem with terminal constraints and singular arcs is proposed. The input functions are parameterized using spline interpolation, which has devices that can represent discontinuous input functions. In order to treat the terminal constraints properly, Lagrange multipliers that are contained in genetic information of chromosomes are introduced. On the singular arcs, coefficients of inputs in Hamiltonian vanish, so the coefficients on the arcs are included in the extended performance index. The weight constants of the extended performance index are changed adaptively at every generation of the genetic algorithm. A simple example is solved using this method, which verifies the efficiency of genetic algorithm in the computation of the optimal control.

Robust control of an absorption heat pump system
A Ohgata, Y Yamashita, H Nishitani
COMPUTERS & CHEMICAL ENGINEERING, 21, Supplement 1, S131, S136, 1997, []

Tracking control using self-organizing neural network
Y Yamashita, Y Ikuno, M Shima
PROCEEDINGS OF THE 35TH IEEE CONFERENCE ON DECISION AND CONTROL, VOLS 1-4, 3804, 3809, 1996, []

Adaptive Multi-Step Learning Control for Time-Varying Linear Systems
YAMASHITA Yuh, MIYAMOTO Junichi, SHIMA Masasuke
Transactions of the Institute of Systems, Control and Information Engineers, 7, 4, 134, 141, THE INSTITUTE OF SYSTEMS, CONTROL AND INFORMATION ENGINEERS (ISCIE), Apr. 1994, []
In this paper, the adaptive multi-step learning control for continuous-time linear system is studied. Input function u_k+1 (t) is calculated from the triplets (u_k, e_k, e_k) and (u_k-1, e_k-1, e_k-1) where e_k is tracking error of k-th trial. The weighting coefficients of the triplets are determined adaptively. The convergence of the control law is proved by means of evaluation of the norm of tracking error. Moreover, the learning control is applied to the tracking problem of two-link robot manipulator.

CMACによる非線形離散時間系のモデル追従制御
山下 裕, 佐藤 友彦, 島 公脩
Transactions of the Institute of Systems, Control and Information Engineers, 4, 6, 245, 251, THE INSTITUTE OF SYSTEMS, CONTROL AND INFORMATION ENGINEERS (ISCIE), Jun. 1991, []
This paper discusses a design method of "neural controller" which achieves the model following control for a SISO nonlinear discrete-time system. If the system dynamics is completely known, the model following control law can be derived as a nonlinear function of input-output sequence via the nonlinear control theory. Under reasonable assumptions, a neural network CMAC-Cerebellar Model Arithmetic Computer-is able to learn both the uncertain nonlinear dynamics of the system and the nonlinear function which yields the model following controller. Moreover, in order to improve the accuracy and the speed of learning, the data presented to the CMAC are transformed by the difference method or the correlation method. It is shown by computer simulations that our method works well and the correlation method is better than the difference method.

Conditions of Invariance and Decoupling for Continuous-time or Discrete-time General Nonlinear Systems
YAMASHITA Yuh, SHIMA Masasuke
Transactions of the Institute of Systems, Control and Information Engineers, 3, 9, 277, 286, THE INSTITUTE OF SYSTEMS, CONTROL AND INFORMATION ENGINEERS (ISCIE), Sep. 1990, []
In our previous paper 4) -12), we have studied "Theory of Invariance" for nonlinear continuous-time systems with their inputs appearing linearly. The aim of this paper is to derive necessary and sufficient conditions that inputs never effect outputs (so called conditions of "Invariance") for nonlinear discrete-time and continuous-time systems without the assumption of linearity in inputs. Applying these conditions to the decoupling problem, we obtained necessary and sufficient conditions which yield decoupling control laws for both the continuous-time systems and the discrete-time systems. The conditions of decoupling given by van der Schaft 13) and Grizzle 14) via geometric approach are different in forms from ours. But, it seems difficult to derive control laws from their conditions because the integration of partial deferential equations is needed there.

一般的な非線形系における入出力線形化
山下 裕, 島 公脩
計測自動制御学会論文集, 26, 9, p1009, 1014, 計測自動制御学会, Sep. 1990

4元数による表現を用いた飛行体の大角度姿勢制御
細川 民樹, 山下 裕, 島 公脩
計測自動制御学会論文集, 26, 4, p467, 473, 計測自動制御学会, Apr. 1990

Theory of Invariance and its Applications-X. Block Decoupling
YAMASHITA Yuh, SHIMA Masasuke
Transactions of the Institute of Systems, Control and Information Engineers, 1, 3, 108, 116, THE INSTITUTE OF SYSTEMS, CONTROL AND INFORMATION ENGINEERS (ISCIE), Mar. 1988, []
In this paper, we study the block decoupling problem of nonlinear systems with C^ω-Structures : x=f (x) +G (x) u, y=h (x). Inputs and outputs are divided into N blocks, respectively. First, we propose a new algorithm by which we can determine the maximal locally controlled invariant distribution contained in Ker dh. This algorithm is an extension of nonlinear structure algorithm extensively used in the input-output linearlization, and can be applied to systems which is not input-output linearlizable. Moreover, it has an advantage in that we need not integrate the distribution.
Application of this algorithm to I-th output block yields a vector valued function z_I(x).Then, the block decoupling problem is solvable if and only if each row of D(G)z_I(x) is zero vector or is linearly independent of rows of other D(G)z_J(x)(J=1, …, N; I≠J). The state feedback control law which accomplishes the block decoupling is derived from z_I(x).

Invarianceの理論とその応用-9-多入力多出力非線形系の出力可制御性
山下 裕, 島 公脩
システムと制御, 31, 6, p450, 456, 日本自動制御協会, Jun. 1987

What has not yet been Realized in Nonlinear Control?
Yuh Yamashita, 計測と制御, 60, 1, 339, 344, May 2021, [Invited], [Lead author]
Japanese, Introduction scientific journal

State Estimation for Distributed Control Systems on Networks with Communication Delays
足立 亮介, 山下 裕, 小林 孝一, システム制御情報学会研究発表講演会講演論文集, 61, 6p, 23 May 2017
システム制御情報学会, Japanese

Asynchronous Control of Networked Control Systems with Decentralized Event-Triggering Conditions
中島 共平, 小林 孝一, 山下 裕, 電子情報通信学会技術研究報告 = IEICE technical report : 信学技報, 116, 433, 31, 34, 27 Jan. 2017
電子情報通信学会, Japanese

Value Assessment of Model Predictive-Based Demand Response
Miyazaki Kodai, Kobayashi Koichi, Azuma Shun-ichi, Yamaguchi Nobuyuki, Yuh Yamashita, Proceedings of the Japan Joint Automatic Control Conference, 60, 344, 347, 2017
The Japan Joint Automatic Control Conference, Japanese

Simultaneous Optimization of Control and Routing for Sensor and Actuator Networks (ITS)
佐藤 大, 小林 孝一, 山下 裕, 電子情報通信学会技術研究報告 = IEICE technical report : 信学技報, 116, 338, 89, 93, 01 Dec. 2016
電子情報通信学会, English

Decentralized Suboptimal Event-triggered Control for Discrete-time Linear Systems
中島 共平, 小林 孝一, 山下 裕, 電子情報通信学会技術研究報告 = IEICE technical report : 信学技報, 115, 442, 13, 16, 29 Jan. 2016
電子情報通信学会, Japanese

Backstepping for a set-valued upper control law
鈴木 大基, 山下 裕, 椿野 大輔, システム制御情報学会研究発表講演会講演論文集, 59, 4p, 20 May 2015
システム制御情報学会, Japanese

Collision Avoidance in LQR-based Formation Control
楠木 孝, 椿野 大輔, 山下 裕, システム制御情報学会研究発表講演会講演論文集, 58, 5p, 21 May 2014
システム制御情報学会, Japanese

Algebras containing Laplacian matrices of some basic graphs
庄司 恵, 椿野 大輔, 山下 裕, システム制御情報学会研究発表講演会講演論文集, 58, 5p, 21 May 2014
システム制御情報学会, Japanese

Vehicle Formation Control based on LQ Optimal Regulator Preserving Triangular Structure
楠木 孝, 椿野 大輔, 山下 裕, システム制御情報学会研究発表講演会講演論文集, 57, 5p, 15 May 2013
システム制御情報学会, Japanese

Numerical Computation of Families of Dissipative Boundaries for Two-Dimensional Gradient-Like Morse-Smale Dynamical Systems
IZUE Yukishige, ENOMOTO Ryuji, YAMASHITA Yuh, The Transactions of the Institute of Electronics, Information and Communication Engineers. A, 95, 3, 261, 267, 01 Mar. 2012
本研究では,大城コンパクトアトラクタをもつような任意に与えられた二次元こう配的Morse-Smale力学系のリヤプノフ関数を求めることを最終目的としている.我々は,これまでに位相幾何学的な手法を利用して正則散逸境界を数値的に算定するアルゴリズムを示した.本論文では,二次元こう配的Morse-Smale力学系の特異散逸境界を含む散逸境界族の数値データを求めるためのアルゴリズムを提案し,その有効性を数値例を用いて示す., The Institute of Electronics, Information and Communication Engineers, Japanese

支部の活動
渡辺 桂吾, 山下 裕, 曽根 秀昭, 寺嶋 一彦, 大薮 多可志, 黒江 康明, 谷口 隆雄, 岡 宏一, 石飛 光章, 計測と制御 = Journal of the Society of Instrument and Control Engineers, 50, 8, 570, 577, 10 Aug. 2011
Japanese

Distributed Coordinative Control for Unknown Work Load
YAMASHITA Yuh, IEICE technical report, 108, 276, 65, 70, 30 Oct. 2008
In this paper, we consider a covering control problem for mobile robots. We propose a control method that cancels the effects of an unknown distributed disturbance and makes the mobile robots move to equalize the canceling loads of all robots. In the model of this paper, the distributed disturbance dynamically increases "work loads" to be treated by mobile robots, while in the model of Cortes et al., 2004, the work loads are given a priori by a known function. The control law of each mobile robot is derived by the passivity theory, and its feedback function consists of spatially local information. Simulation of the covering problem shows the effectiveness and some problems of the proposed method., The Institute of Electronics, Information and Communication Engineers, Japanese

Solutions of Systems with Discontinuous Control and a Global Asymptotic Stabilization Problem
TSUZUKI Takayuki, YAMASHITA Yuh, Systems, control and information, 52, 3, 84, 89, 15 Mar. 2008
Institute of Systems, Control and Information Engineers, Japanese

Markov過程の量子化を用いた確率的Lyapunov関数の構築—Stochastic Lyapunov function design using quantization of Markov process—非線形問題
西村 悠樹, 山下 裕, 電子情報通信学会技術研究報告 = IEICE technical report : 信学技報, 107, 399, 47, 52, 19 Dec. 2007
東京 : 電子情報通信学会, Japanese

Robust analysis of a discontinuous control system
TSUZUKI Takayuki, YAMASHITA Yuh, IEICE technical report, 107, 399, 43, 46, 12 Dec. 2007
For nonlinear control systems defined on general manifolds, it is known that there there exist neither continuous global asymptotic stabilizer and control Lyapunov function. A general control Lyapunov function is propsoed to solve the stabilization problem. This paper shows that if a general control Lyapunov function exists for a nonlinear system, there exists a discontinuous global asymptotic stabilizer. Moreover, a robustness with respect to a disturbance is analyzed., The Institute of Electronics, Information and Communication Engineers, Japanese

Output Regulation of Nonlinear Control Systems
YAMASHITA Yuh, Journal of The Society of Instrument and Control Engineers, 42, 10, 821, 826, 10 Oct. 2003
The Society of Instrument and Control Engineers, Japanese

非線形系の出力レギュレーション問題 (特集 非線形性に挑む--システム制御理論の最前線)
山下 裕, 計測と制御, 42, 10, 821, 826, Oct. 2003
計測自動制御学会, Japanese

On the Compensation for Transmission Delay and Data Loss in Remote Control Systems
YAMASHITA Yuh, Journal of The Society of Instrument and Control Engineers, 41, 7, 513, 518, 10 Jul. 2002
The Society of Instrument and Control Engineers, Japanese

Estimation of Logical Thinking State Using EEGs
YAMAKAWA Masashi, KUROOKA Taketoshi, YAMASHITA Yuh, NISHITANI Hirokazu, Human Interface, 2, 3, 7, 12, 16 Jun. 2000
ヒュ-マンインタフェ-ス学会, Japanese

非線形制御--日本学術振興会143委員会WS19報告 (特集 新時代を担う計装・情報化テクノロジー --その可能性を探る--計装・情報化テクノロジーの活用視点と役割)
山下 裕, 計装, 43, 1, 25, 29, Jan. 2000
工業技術社, Japanese

Applications of the genetic algorithm for control problems
Shima M., Yamashita Y., 物性研究, 66, 4, 659, 662, 1996
物性研究刊行会, Japanese

Output tracking control for nonlinear singularly perturbed systems
Yamashita Y, Kishi N, Shima M, Bulletin of the Faculty of Engineering, Hokkaido University, 167, 0, 157, 167, Jan. 1994
Hokkaido University, Japanese

Feedback Design for General Nonlinear Systems
YAMASHITA Yuh, 計測と制御 = Journal of the Society of Instrument and Control Engineers, 31, 8, 859, 864, 10 Aug. 1992
計測自動制御学会, Japanese

ニュ-ラルネットワ-クによる学習・適応制御 (ニュ-ラルネット<特集>)
山下 裕, 島 公脩, 石動 善久, 計測と制御, 30, 4, p302, 308, Apr. 1991
計測自動制御学会, Japanese

非線形制御系の設計アルゴリズムとCAD (非線形システム特集号)
石動 善久, 山下 裕, 島 公脩, システム・制御・情報, 33, 9, p445, 453, Sep. 1989
システム制御情報学会, Japanese

非線形システム制御論
島 公脩, 石動 善久, 山下 裕, 渡邉 昭義, 川村 武, 横道 政裕
コロナ社, 1997, 4339031674, Japanese

「非線形システム論」　　　　　　　　　　　　　　　
計測自動制御学会, 1993

システム制御理論特論　　　　　　　　　　　　　　　
北海道大学
Apr. 2014 - Present

メカトロニクス基礎　　　　　　　　　　　　　　　
北海道大学
Apr. 2011 - Present

ディジタル制御　　　　　　　　　　　　　　　
北海道大学
Oct. 2009 - Present

線形システム論　　　　　　　　　　　　　　　
北海道大学
Oct. 2004 - Present

非線形システム論　　　　　　　　　　　　　　　
北海道大学
Oct. 2004 - Mar. 2006

Parametric deformation of control Lyapunov function for nonlinear systems and its applications
Grants-in-Aid for Scientific Research
01 Apr. 2023 - 31 Mar. 2026
山下 裕, 小林 孝一
非線形系に対し予め与えられた 2つの(局所)制御リアプノフ関数を無数の関数で補間しそれらを最小射影法で合成することで元の2つの制御リアプノフ関数をblendingする手法を明らかにした。そこで現れる部分的な最小化問題は2次方程式を解くことで合成制御リアプノフ関数を得ることができるため、提案法のアルゴリズムではオンラインで計算することが可能である。この方法によって得られた合成局所制御リアプノフ関数さらに複数合成し、ステアリング角制限を持つ移動ロボットの制御問題に応用した。その際に経路設計は非巡回的有効グラフの構造によって指定できる。非巡回的有効グラフの半順序にしたがってオフセットを与えることよって最終的な制御リアプノフ関数を得ることができた。非巡回的有効グラフによって経路設計を大まかに指定できることが利点であり、非巡回的有効グラフやオフセットを変更するだけで経路を動的に再設計できるのが利点である。
さらに、これを3つ以上の制御リアプノフ関数blendingの場合へと拡張する試みを行った。その際のオンライン計算においては4次方程式を解く必要があることを明らかにし，試験的なプログラムを作成した。
また、フィードバック対称性を持つ非線形系に対し、その対称性を用いた制御リアプノフ関数合成手法について研究を行った。可制御な1入力線形系は、本研究での意味のフィードバック対称性を持つことを明らかにした。対称性のパラメータを制御リアプノフ関数候補の値そのものの関数で与える場合を考察し、その場合得られる陰的方程式の解の唯一性の仮定の下で得られる関数が制御リアプノフ関数の性質を保持していることを明らかにした。
Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (B), Hokkaido University, 23K26124

Satellite-based evaluation of air quality improvements in logistics
Grants-in-Aid for Scientific Research
01 Apr. 2023 - 31 Mar. 2026
太田 充, 牛島 光一, 山下 裕
本研究は、中国における高速鉄道の貨物輸送への移行が大気汚染と公衆衛生に与える影響を測定することを目的とする。具体的には、自動車輸送から鉄道輸送への移行が大気中の二酸化炭素濃度にどのような影響を与えるかを解析するために、JAXAから提供される衛星データを用いる。この研究により、交通手段の変更が大気質の改善にどれほど寄与するかの科学的証拠が提供され、環境政策や都市計画における政策提言に資することが期待される。
自動車排出ガスは大気汚染の主要な原因であり、特に急速に都市化が進む中国での汚染問題は深刻である。高速鉄道は輸送効率が高く、排出ガスが少ないため、これを利用することで大気汚染の削減が期待される。本研究では、衛星データを用いて、高速鉄道路線が開通した地域とそうでない地域の大気汚染データを比較分析し、鉄道輸送の普及が大気汚染削減にどのような効果をもたらすかを科学的に評価する。
さらに、本研究は大気汚染が公衆衛生に及ぼす影響にも焦点を当てる。大気汚染は呼吸器疾患や心血管疾患のリスクを高めることが知られており、鉄道輸送がこれらの健康リスクを減少させる可能性を探る。研究結果は、交通政策のみならず、都市計画や環境政策の分野においても重要な示唆を提供することが期待され、持続可能な輸送システムの構築と都市の持続可能性向上に貢献する。
総じて、本研究は環境保護、公衆衛生の向上、経済的効率の向上に寄与する可能性があり、科学的根拠に基づいた政策提言が可能となることで、広範な社会的利益をもたらすことが期待される。また、衛星データを用いる新しい研究方法論は、今後の大気汚染研究において重要な役割を果たすであろう。
Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (C), University of Tsukuba, 23K01369

Energy saving control using discontinuous or non-positive definite input cost
Grants-in-Aid for Scientific Research
01 Apr. 2019 - 31 Mar. 2022
Yamashita Yuh
Considering an energy-saving optimal control problem when the target value of the state does not coincide with the stationary point of minimum energy consumption, we formulated the problem by slightly modifying the input cost function from the natural energy consumption and constructed a nonlinear optimal regulator that guarantees asymptotic stability. In addition, when actuators require standby power, the operation of deactivating inefficient actuators according to the value of the state values contributes to energy conservation in redundant input systems. We proposed an optimal controller design method that performs such an operation. We also proposed a control method that includes suspending the communication of sensor values according to output values.
Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (B), Hokkaido University, 19H02157

制御リアプノフ関数を用いた入力分配制御
科学研究費補助金(基盤研究(B))
Apr. 2016 - Mar. 2019
山下 裕
日本学術振興会, Principal investigator, Competitive research funding

Development of topological control theory for decision making
Grants-in-Aid for Scientific Research
01 Apr. 2015 - 31 Mar. 2018
Nakamura Hisakazu
This research aims to design a framework of combining decision and control from the view point of topology. The major achievements are as follows. Development of a control strategy that dynamically identifies the desired state by the minimum projection method, development of the local minimum connection method for static control Lyapunov function design, and development of a human safety assist control strategy by using control barrier functions. By the preceding achievements, this research elucidates that a control Lyapunov function and a control barrier function are effective for the combination of decision and control.
Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (B), Tokyo University of Science, 15H04022

Radon測度上の動的システムの研究と都市構造遷移モデルへの応用
科学研究費補助金(挑戦的萌芽研究)
Apr. 2014 - Mar. 2017
山下 裕
日本学術振興会, Principal investigator, Competitive research funding

Nonlinear control theory based on generalized semiconcave functions
Grants-in-Aid for Scientific Research
01 Apr. 2011 - 31 Mar. 2014
NAKAMURA Hisakazu, YAMASHITA Yuh, ITO Hiroshi, ENOMOTO Ryuji, FUKUI Yoshiro
We proposed feed back controller design method by using disassembled differential. Moreover, we confirmed that our proposed method is available for input constrained control systems.
We proved that Jurdjevic-Quinn type controllers permit local Caratheodory solutions of closed-loop systems.
We analyzed desingularization phenomena on our proposed minimum projection method, and proposed a singular point assignment method for nonsmooth control Lyapunov function design. Moreover, we proposed static control Lyapunov function and static controller design methods based on dynamic extention and the minimum projection method.
Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (B), Tokyo University of Science, 23360185

Stability Analysis of Dynamical Systems on Topological Spaces
Grants-in-Aid for Scientific Research
2011 - 2013
NAKAMURA Nami, YAMASHITA Yuh, NAKAMURA Hisakazu
We have defined Lagrange stability and input-to-state stability for nonlinear systems on manifolds. Furthermore, we have presented necessary and sufficient conditions for stability by using continuous positive definite proper functions. We have designed an ISS-control Lyapunov function and an input-to-state stabilizing controller for an obstacle avoidance problem of a mobile robot. Then, we have confirmed the effectiveness of the proposed controller by computer simulation. We have proposed a sample input-to-state stabilizing controller for general nonlinear systems on manifolds.
Japan Society for the Promotion of Science, Grant-in-Aid for Young Scientists (B), Tokyo University of Science, 23760391

Study on the nonlinear control using transformation to state-jump system
Grants-in-Aid for Scientific Research
2010 - 2012
YAMASHITA Yuh, NAKAMURA Hisakazu, NISHIDA Gou, NISHIMURA Yuki, TSUZUKI Takayuki
his study proposes a framework of control system design methodologies bywhich the state space of a dynamical controlled object is extended by adding new continuous or discretecoordinates and a desired closed-loop is designed on the augmented space allowing state-jumps on thenew coordinates. Furthermore, methods of the degeneracy of the extended space for obtaining adiscontinuous static feedback law or a control law with discrete states are given. By introducingstate-jumps, we can construct a controller mathematically even for decision-making problems of thedynamical systems.
Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (B), Hokkaido University, Principal investigator, Competitive research funding, 22360167

Establishment of nonlinear control theory taking into account global structure of manifold
Grants-in-Aid for Scientific Research(基盤研究(C))
2007 - 2009
Yuh YAMASHITA, Hisakazu NAKAMURA, Gou NISHIDA, Yuki NISHIMURA
This study presents a general framework for controlling nonlinear systems on general manifolds including non-Euclidean spaces which precedent control theories cannot handle. Global attitude control of satellites, obstacle avoidance of vehicles, and control of acrobots are examples of our problem. This framework provides design procedures generating control laws automatically with discontinuity, logic, or randomness, of which properties are necessary to stabilize such systems on non-Euclidean spaces.
Ministry of Education, Culture, Sports, Science and Technology, 基盤研究(C), 北海道大学, Principal investigator, Competitive research funding, 19560435

Development of Plant Operator Model Incorporating Mental and Physical States
Grants-in-Aid for Scientific Research(基盤研究(B))
2002 - 2005
Hirokazu NISHITANI, 今福 啓, 黒岡 武俊, 山下 裕, 小坂 洋明, 中村 文一
This project aimed at understanding plant operator's behavior under abnormal situations through dynamic simulation by using some cognitive information processing model incorporating the mental and physical states and proposing some method to create appropriate countermeasures. We obtained the following three main results.1.We installed a new plant operator model that is a cognitive information processing model incorporating the mental and physical states on a PC and connected to an industrial boiler plant simulator for operator training. This operator model was used in analyzing the various...
Ministry of Education, Culture, Sports, Science and Technology, 基盤研究(B), 奈良先端科学技術大学院大学, Coinvestigator not use grants, Competitive research funding, 14380179

Control system design using non-smooth feedback
Grants-in-Aid for Scientific Research(基盤研究(C))
2003 - 2004
Yuh YAMASHITA, 中村 文一
1.We obtained a simple expression of the converse Lyapunov theorem for discontinuous systems. Also, the converse Lyapunov theorem for discontinuous homogeneous systems with dilations was developed, which shows that each discontinuous homogeneous strongly stable system with dilation has a homogeneous Lyapunov function. It was shown that the degree of homogeneity indicates the speed of the convergence, i.e. a homogeneous strongly stable system with a negative degree of homogeneity has a finite-time convergence property. The proof of the finite time convergence of high-order sliding mode contr...
Ministry of Education, Culture, Sports, Science and Technology, 基盤研究(C), 奈良先端科学技術大学院大学->北海道大学, Principal investigator, Competitive research funding, 15560378

Study on the construction of control theory by the notion of invariance and the development of its introductory course
Grants-in-Aid for Scientific Research(基盤研究(C))
2001 - 2003
Masasuke SHIMA, 横道 政裕, 川村 武, 石動 善久, 山下 裕, 榎本 隆二
Firstly, the role of invariance in the control theory is studied [1]Invariance with respect to the variation of parameters : Using Frazer-Duncan theorem and monotonicity conditions, we derived a necessary and sufficient condition for the stability of linear systems without regard to the variation of interval parameters, and presented a monotonization method for the system which is not monotone. [2]Feedback design considering structures of Lie algebra : Feedback stabilization and improvement of tracking properties ties are studied for the under actuated mechanical systems such as axi-symmetr...
Ministry of Education, Culture, Sports, Science and Technology, 基盤研究(C), 北海道大学, Coinvestigator not use grants, Competitive research funding, 13650479

Control Design for Nonlinear System Described by Differential-Algebraic Equations
Grants-in-Aid for Scientific Research(基盤研究(C))
2000 - 2002
Yuh YAMASHITA, 黒岡 武俊
In this research, we study controller design of nonlinear systems described by differential-algebraic equations (DAE). In nonlinear cases, it is hard to convert the system to ordinary differential equations (ODE) without redundancy, because nonlinear algebraic equations cannot be solved analytically in general.First, for nonlinear DAE systems with index one, a design method of exact I/O-linearizing control and observer is proposed, where the global-stability condition of the observer is also obtained. The estimated state variables in the observer converge to an invariant manifold determined...
Ministry of Education, Culture, Sports, Science and Technology, 基盤研究(C), 奈良先端科学技術大学院大学, Principal investigator, Competitive research funding, 12650446

Estimation of a Plant Operator's Mental State and its Application to Operator Support
Grants-in-Aid for Scientific Research(基盤研究(B))
2000 - 2001
Hirokazu NISHITANI, 黒岡 武俊, 山下 裕
We have been studying the use of multiple channel elecroencephalogram (EEG) data to infer a human's thinking state. As a result, we have confirmed off-line thinking state estimation to be effective, in experimental studies on simulator training during malfunctions and mathematical problem solving. In this research, we reconsidered the mathematical model for thinking state estimation and concluded that an artificial neural network (ANN) model is more appropriate for real-time use than the linear regression model.We developed a prototype real-time thinking state monitoring system with the ANN...
Ministry of Education, Culture, Sports, Science and Technology, 基盤研究(B), 奈良先端科学技術大学院大学, Coinvestigator not use grants, Competitive research funding, 12480098

Modeling and Simulation of Plant-Wide Control Systems
Grants-in-Aid for Scientific Research(基盤研究(C))
1997 - 1998
Hirokazu NISHITANI, 北島 禎二, 黒岡 武俊, 山下 裕
In this study, plant-wide control is regarded as the total activities generated by feedback control for continuous processes, sequential control for discrete events and supervisory control for process malfunction and equipment failure. The integration of these control elements enables safe and efficient plant control or operation. However, there is no theory for design of the plant-wide control system. Dynamic simulation is the only way to handle such a large and complicated system. In the first year, we investigated modeling and simulation techniques to evaluate system performances of a pl...
Ministry of Education, Culture, Sports, Science and Technology, 基盤研究(C), 奈良先端科学技術大学院大学, Coinvestigator not use grants, Competitive research funding, 09650830

Robust Design of Nonlinear Control Systems
Grants-in-Aid for Scientific Research(一般研究(B))
1994 - 1995
Masasuke SHIMA, 川村 武, 山下 裕, 石動 善久
In this year, we have obtained the following results.1.The nonlinear non-standard H^* control problem is studied. In this research, two cases are concerned with : (a) the case in which the direct-through term from the input to the output does not have full-rank, and (b) the case in which the direct-through term from the disturbance to the measurement output does not have full-rank. In these cases, the square compliment cannot be carried out with the usual method, and thus the Hamilton-Jacobi-Issacs partial differential inequality is not well-defined. To resolve this difficulty, the term inc...
Ministry of Education, Culture, Sports, Science and Technology, 一般研究(B), 北海道大学, Coinvestigator not use grants, Competitive research funding, 06452248

ハミルトン・ヤコビ偏微分方程式の数値解法
科学研究費補助金(奨励研究(A))
1994 - 1994
山下 裕
本研究では、以下の成果を得た。・正準方程式の安定多様体がハミルトン・ヤコビ偏微分方程式の解であることを利用し、時間軸を逆にとることによって、常微分方程式の数値解法に帰着させた。・上記の常微分方程式を数値的に解くにあたって、その初期点を与えるアルゴリズムを開発した。具体的には、初期サンプル点を一様に分布させ、安定多様体上の線形近似式を用いて原点近傍までシミュレートし、さらに安定多様体の1次近似を用いて2n次元の初期点を得る方法を開発した。原点近傍までの所要時間をもとに・得られた解曲線をBezier補間式で最小2乗近似し、状態量χの関数として表現した。その関数を用いて制御器を作ることが可能となった。・上記の手法を基に、購入したワークステーション上に、目的の解を高精度に得る解法パッケージを開発した。・本方法の特長の1つは、得られた解曲線の存在範囲によって、得られた解の有効な定義域が推定できることである。これは、原点でのTaylor展開による従来の方法ではできなかったことである。
文部科学省, 奨励研究(A), 北海道大学, Principal investigator, Competitive research funding, 06750426

遺伝的アルゴリズムによる制御
科学研究費補助金(奨励研究(A))
1993 - 1993
山下 裕
本研究に関する研究実績は以下の通りである。1.遺伝的アルゴリズムを最適制御問題、特に最適特異制御問題の数値解法に応用した。最適制御問題の数値解法として幾つかの方法が知られているが、最適特異制御問題を解くことのできる方法は非常に少ない。本研究では、遺伝子上に幾つかの時間の点における入力の大きさをコーディングし、3次スプライン曲線でそれらをつないで、制御入力とした。最適制御においては、入力の関数が不連続となることが多いので、遺伝子上には不連続となる場所に関する情報も加えた。本研究では、槽式流通反応系の最適コスト問題に対し、これらの方法を適用したが、bang-bang制御の区間と最適特異軌道の区間が明確に現れ、良好な結果を得た。これらの成果に関して、現在、投稿準備中である。2.遺伝的アルゴリズムをファジイ制御に応用し、シミュレーションを繰り返すことによりファジイルールを自動生成する研究をおこなった。ファジィ制御の前件部の取りうるすべての組み合わせに対して、その後件部を遺伝子上にコーディングし、オフラインでシミュレーションを繰り返し遺伝的アルゴリズムを用いることで、ファジイルールを自動生成した。本研究では、この方法を車両の障害物回避問題に適用した。試行結果の評価値のみの情報で、ランダムなファジイルールが次第に、障害物を回避し目標に到達するように進化した。これらの成果に関しては、さらに...
文部科学省, 奨励研究(A), 北海道大学, Principal investigator, Competitive research funding, 05855056

A Study of the System Theory via Controlled Path Integral
Grants-in-Aid for Scientific Research(一般研究(C))
1991 - 1992
Masasuke SHIMA, 山下 裕, 石動 善久
In this research project, we studied the possibility of system theory based on the controlled path integrals. The dynamical behavior of the system is described by a vector field X=X_0+X_1u^1+...+X_mu^m defined on a manifold M as a state space. u=(u^1,...,u^m) are control inputs to the system. The control u(t) given on [t_0,t_1] deter mines the state trajectory p(t). Assuming that a differential form omega is given and integrating omega(X) along the trajectory, we obtain the controlled path integral associated with omega and X. Outputs of a system, Lyapunov function and the performance index...
Ministry of Education, Culture, Sports, Science and Technology, 一般研究(C), 北海道大学, Coinvestigator not use grants, Competitive research funding, 03805020

非線形制御理論　　　　　　　　　　　　　　　
Competitive research funding

Nonlinear control theory　　　　　　　　　　　　　　　
Competitive research funding