川口 夏樹

A dual-rate sampled-data control system is designed in which the sampling interval of measured signals is twice as long as the holding interval of a control input. In the proposed method, a control law is extended based on the null space and intersample ripples are eliminated without changing the sampled output trajectory in the steady state. Polynomial and state-space approaches are conventional open-loop design methods based on the null space. However, conventional methods are ineffective for unstable systems and are unavailable when the null space of the plant model is only the zero vector because the controlled plant is not arbitrarily selectable. On the other hand, the proposed method is effective for unstable systems, as well as stable systems, even when the null space of the plant model is only the zero vector, because the proposed controller is designed based on a closed-loop system.

© 2019 IEEE. Multi-agent systems (MASs) are used for distributed control purposes and substantial research attention has been directed to these systems because of their practical merits. In MASs, agents' information is shared through networks. In networked-control systems, the measured data is usually quantized because of sensor performance or specification, and its resolution is inadequate. Furthermore, because of network quality, the measurement interval is often longer than the control interval. Therefore, the present study introduces a design method for a dual-rate quantized control system, in which the measurement interval of agents is an integer multiple of the control interval.

© 2018 IEEE. Since Almost strictly positive real (ASPR) condition is satisfied using the parallel feedforward compensator (PFC), the stable control system is easily designed with simple adaptive control (SAC) method. The augmented system output, in which the PFC is included, converges to the reference model output, and on the other hand, there is the steady-state error between the actual system output with the reference model output because of the PFC. In this study, an SAC law is extended using the null-space for controlling a rotation control system.