Keiji Watanabe

Feedback error learning control without recourse to positive realness

Feedback error learning (FEL) method has been proposed by Kawato et al. as a scheme of brain motor control in neurophysiology. Recently, Miyamura and Kimura have established a control theoretical validity of the FEL method in the framework of adaptive control and proved its stability based on the strictly positive realness. In this note, we propose another scheme for the feedback error learning method which does not require any positive real conditions.

Three-Degree of Freedom Internal Model Control

To improve the robustness and disturbance rejection performances of the control system, a three-degree of freedom control design algorithm that extended from internal model control is proposed. For robustness of the control system, which based on the knowledge of the model uncertainties, the internal model control structure is adopted together with an additive robust compensator. The controller used for disturbance rejection is designed according to sensitivity function of the three-degree of freedom control system. The straightforward timing of few parameters gives the technique its practicality. Numerical examples are given to illustrate the algorithm, which provides verification and insight

A note on the two disk mixed sensitivity design for control system with multiple output time delays

Abstract This note presents a tuning design method for output time delayed control systems that satisfies the two disk mixed sensitivity control design specification. The key features of this method are that it focuses on the two disk mixed sensitivity problem; it handles multiple time delays and allows the majority of the calculations to be carried out as in the time delay free case. A numerical example is given to show how the procedure works.

Three-degree-of-freedom internal model control for unstable process

A new design algorithm of three degree of freedom (3DOF) internal model control (IMC) for unstable process is presented in this paper. A robust compensator is introduced into the system to improve the robustness and the compensator in feedback loop not only can be used to stabilize the unstable process, but also for disturbance rejection. Followed the presented criterion for robust stability, the design technique is demonstrated by a numerical simulation example to give its practicability in industrial control applications.

Adaptive Internal Model Control of MIMO Systems via State Equations

This paper considers an internal model control scheme for multi-input multi-output systems which contain unknown parameters in the coefficient matrices of the state equations. The internal model is adaptively constructed from input and output signals of the plant. We first propose a linear parametric representation for the unknown multi-input multi-output systems. Then, we present an adaptation method such that the output of the internal model is asymptotically identical to that of the plant, guaranteeing stability of the closed-loop system.

Control design for a certain class of output time delayed systems under the two disk mixed sensitivity specification

Abstract This work deals with the realization of the controller for output time delayed systems with multiple delays. It is shown that the controller established here yield an internally stable system. Furthermore, it is presented a condition for the two disk mixed sensitivity specification be met.