Hiroshi Takenaga

A Design Method of Simple Multi-period Repetitive Controllers

The multi-period repetitive control system is a type of servomechanism for periodic reference input. Even if the plant does not include time-delay, the transfer function from the reference input to the output and that from the disturbance to the output of the multi-period repetitive control system generally have an infinite number of poles. In order to specify the input-output characteristic and the disturbance attenuation characteristic easily, we propose the concept of simple multi-period repetitive control systems such that the controller works as a stabilizing multi-period repetitive controller and the transfer function from the reference input to the output and that from the disturbance to the output have a finite number of poles. In addition, the parametrization of all stabilizing simple multi-period repetitive controllers is clarified.

A design method of robust stabilizing simple multi-period repetitive controllers

Abstract A multi-period repetitive control system is a type of servomechanism for a periodic reference input. Even if a plant does not include time-delay, the transfer function from the periodic reference input to the output and that from the disturbance to the output of the multi-period repetitive control system generally have an infinite number of poles. In order to specify the input-output characteristic and the disturbance attenuation characteristic easily, Yamada et al. propose the concept of simple multi-period repetitive control systems such that the controller works as a stabilizing multi-period repetitive controller and the transfer function from the periodic reference input to the output and that from the disturbance to the output have a finite number of poles. However, the method by Yamada et al. cannot apply for the plant with uncertainty. The purpose of this paper is to propose the concept of robust stabilizing simple multi-period repetitive controllers for the plant with uncertainty and to clarify the parametrization of all robust stabilizing simple multi-period repetitive controllers.

A Design Method for Smith Predictor for Non-Minimum-Phase Time-Delay Plants with Multiple Time-Delays

In this paper, we examine a design method for modified Smith predictor for non-minimum-phase time-delay plants with multiple time-delays. The modified Smith predictor is well known as an effective time-delay compensator for a plant with large time-delay, and several papers on the modified Smith predictor have been published. The parametrization of all stabilizing modified Smith predictors for minimum-phase time-delay plants is obtained by Yamada and Matsushima. Yamada et al. expand the result by Yamada and Matsushima and propose the parametrization of all stabilizing modified Smith predictor for non-minimum-phase systems. In some cases, the plant includes multiple time-delays. For minimum-phase timedelay plants with multiple time-delays, the parametrization of all stabilizing modified Smith predictors is solved by Yamada and Takenaga. However, they do not examine the parametrization of all stabilizing modified Smith predictors for non-minimum-phase time-delay systems with multiple time-delays. The purpose of this paper is to expand the result by Yamada and Takenaga and to propose the parametrization of all stabilizing modified Smith predictors for non-minimum-phase time-delay plants with multiple time-delays.

A design method for simple repetitive controllers for time-delay plants

The modified repetitive control system is a type of servomechanism for the periodic reference input. Using previously proposed modified repetitive controllers, even if the plants does not includes time-delay, the transfer function from the periodic reference input to the output and that from the disturbance to the output have an infinite number of poles. From the practical point of view, it is desirable that the transfer function from the periodic reference input to the output and that from the disturbance to the output have a finite number of poles. Yamada et al. proposed the concept of simple repetitive control systems such that the controller works as a modified repetitive controller and the transfer function from the periodic reference input to the output and that from the disturbance to the output have a finite number of poles. In addition, Yamada et al. clarified the parametrization of all stabilizing simple repetitive controllers. However the method by Yamada et al. cannot be applied for time-delay plants. The purpose of this paper is to propose the parametrization of all stabilizing simple repetitive controllers for time-delay plants.

A design method for robust stabilizing simple repetitive control systems

The modified repetitive control system is a type of servomechanism for the periodic reference input. That is, the modified repetitive control system follows the periodic reference input with small steady state error, even if a periodic disturbance or uncertainty exists in the plant. Using previously proposed modified repetitive controllers, even if the plants does not includes time-delay, the transfer function from the periodic reference input to the output and that from the disturbance to the output have an infinite number of poles. When the transfer function from the periodic reference input to the output and that from the disturbance to the output have an infinite number of poles, it is difficult to specify the input-output characteristic and the disturbance attenuation characteristic. From the practical point of view, it is desirable that the input-output characteristic and the disturbance attenuation characteristic are easily specified. In order to specify the input-output characteristic and the disturbance attenuation characteristic easily, the transfer function from the periodic reference input to the output and that from the disturbance to the output are desirable to have a finite number of poles. Yamada et al. proposed the concept of simple repetitive control systems such that the controller works as a modified repetitive controller and the transfer function from the periodic reference input to the output and that from the disturbance to the output have a finite number of poles. In addition, Yamada et al. clarified the parametrization of all stabilizing simple repetitive controllers. However the method by Yamada et al. cannot be applied for the plant with uncertainty. The purpose of this paper is to propose the parametrization of all robust stabilizing simple repetitive controllers for the plant with uncertainty.

A Design Method of Simple Multi-Period Repetitive Controllers for Time-Delay Plants

The multi-period repetitive control system is a type of servomechanism for periodic reference input. Even if the plant does not include time-delay, the transfer function from the reference input to the output and that from the disturbance to the output of the multi-period repetitive control system generally have an infinite number of poles. In order to specify the input-output characteristic and the disturbance attenuation characteristic easily, the concept of simple multi-period repetitive control systems such that the controller works as a stabilizing multi-period repetitive controller and the transfer function from the reference input to the output and that from the disturbance to the output have a finite number of poles is presented by Yamada and Takenaga. However, the method by Yamada and Takenaga cannot apply for time-delay plants. In this paper, we propose a design method for simple multi-period repetitive controllers for time-delay plants.

The Parametrization of All Stabilizing Smith Predictors for Certain Class of Non-Minimum Phase Time-Delay Plants

In this paper, we examine the parametrization of all stabilizing modified Smith predictors for certain class of non-minimum phase time-delay plants. The modified Smith predictor is well known as an effective time-delay compensator for a plant with large time-delay. Several papers on the modified Smith predictor have been published. In order to express the past studies of modified Smith predictor in an uniform manner, Yamada and Matsushima gave the parametrization of all stabilizing modified Smith predictors for minimum phase time-delay plants. However, the method by Yamada and Matsushima cannot apply for non-minimum phase time-delay plants. The purpose of this paper is to propose the parametrization of all stabilizing modified Smith predictors for certain class of non-minimum phase time-delay plants