Simple Adaptive Control System Research Articles

The design method of simple adaptive control system with PFC for MIMO system via DE

This paper deals with a design method of adaptive output feedback control system with parallel feedforward compensator (PFC) for a multiple input multiple output system. An adaptive output feedback control system, which is based on almost strictly positive real (ASPR), requires PFC in most cases. The design method is using one-shot input/output data of the controlled system, and parameter optimization will be done by differential evolution (DE). By using DE, the designer can optimize the design parameters without trial and error, which can be a more practical method.

Transient Response Improvement Using Disturbance Compensator for the Simple Adaptive Control System with the Null-space Adjustor

Transient Response Improvement Using Disturbance Compensator for the Simple Adaptive Control System with the Null-space Adjustor

Simple Adaptive Control Against Sensor Failures

In various fields, for practical plants, Simple Adaptive Control (SAC) has provided good control performances in spite of its simple structure. Although many theories and applications of the SAC have been explored, sensor failure issues have not been well considered. As a remedy, in the previous work, a fault-tolerant SAC system (SACS) is developed that can automatically replace failed sensors with healthy backups to maintain its performance. However, an additional condition is imposed on controlled plants, and a class of detectable failures is slightly limited. This problem comes from a design of detection filters introduced to the SACS. In this paper, to remove the above-mentioned restrictions, a new design method for a nonlinear detection filter is presented. This paper also shows a theoretical analysis on control performance and several simulation results to confirm the effectiveness.

On simple adaptive control of plants not satisfying almost strict passivity and positivity conditions: an introduction to parallel feedforward configuration

Simple adaptive control systems were known to be robust against a class of disturbances and globally stable if the controlled plant is almost strictly positive real, that is, if there exists a positive definite static output feedback (unknown and not needed for implementation) such that the resulting closed-loop transfer function is strictly positive real. The present paper discusses the simple adaptive control scheme for a non-almost strictly positive real plants and gives a brief review of the parallel feedforward which makes the augmented plant satisfy the almost passivity or positivity conditions based on the stabilisability property of the system. The validity of the simplified adaptive algorithm under the positivity condition is examined through numerical simulation for both single-inputs single-outputs and multi-inputs multi-outputs systems.

On simple adaptive control of plants not satisfying almost strict passivity and positivity conditions: an introduction to parallel feedforward configuration

Simple adaptive control systems were known to be robust against a class of disturbances and globally stable if the controlled plant is almost strictly positive real, that is, if there exists a posi...

Adopting Simple Adaptive Control System for Wheeled Mobile Robot to Driving Control on the Road Surface Variation

Adopting Simple Adaptive Control System for Wheeled Mobile Robot to Driving Control on the Road Surface Variation

Adaptive Speed Control of Wheeled Mobile Robot on Uncertain Road Condition

[abstFig src='/00280005/10.jpg' width='300' text='Adaptive speed control for mobile robot' ] This study investigated the effectiveness of a simple adaptive control system used for controlling the dynamics of the driving system of a wheeled mobile robot. This paper describes the design method of a speed control system and the gain adjustment procedure considering a practical application of the simple adaptive control system. Experiments were conducted on two different road conditions, and the results indicated that the rectilinear performance of the wheeled mobile robot improved with the use of the simple adaptive control system. In the case of uncertain road conditions, the simple adaptive control system reduced the deterioration of the control performance effectively.

S1150205 空気圧マニピュレータによる制御性能に関する研究

The biggest problem of using a pneumatic system in an actuator is the difficulty of handling caused by the compressibility of air. This is especially true when taking measures for stick-slip phenomenon that occurs when driving cylinders at low speeds. This paper identifies nonlinear friction which is the main cause of stick-slip phenomenon using the LuGre friction model and examines its effect using a simulation model. This paper also examines and reports the improvement of position control using Simple Adaptive Control System.

2A2-A07 路面摩擦変化を考慮した単純適応制御系による車輪型移動ロボットの速度制御(車輪型/クローラ型移動ロボット(2))

2A2-A07 路面摩擦変化を考慮した単純適応制御系による車輪型移動ロボットの速度制御(車輪型/クローラ型移動ロボット(2))

A Study of Simple Adaptive Control System of Electrical Stimulation for Upper Limb Motion

A Study of Simple Adaptive Control System of Electrical Stimulation for Upper Limb Motion

単純適応制御系設計におけるスケーリングの導入と拮抗型空圧人工筋駆動機構の位置決め制御への応用

In this paper, we aim at achieving accurate positioning control of a pneumatic actuation mechanism of antagonist-type by means of the simple adaptive control (SAC) method. Since this plant does not satisfy the ASPR-ness condition, we introduce a parallel feedforward compensator (PFC) so that the SAC strategy can be applied. However, the introduction of PFC leads to performance deterioration and in particular causes a steady state error. To suppress the steady-state error while keeping the fundamental structure of the SAC system, we introduce a “constant scaling” to the SAC system. We also consider a “dynamic scaling” so that the transient response of the controlled system can be improved. Through experiments, we show that the SAC strategy with these scalings is indeed effective in achieving accurate positioning control.

相対次数モデルに基づく2-Delay入力ゲイン適応制御系の設計とその応用(OS1 先端制御理論と機械システムへの応用)

相対次数モデルに基づく2-Delay入力ゲイン適応制御系の設計とその応用(OS1 先端制御理論と機械システムへの応用)

構造の簡単な適応制御系の設計法とそのロバスト性

構造の簡単な適応制御系の設計法とそのロバスト性

不確かさをもつプロセス系に対する単純適応制御系設計

不確かさをもつプロセス系に対する単純適応制御系設計

A Discrete-Time SAC System with No Output Tracking Error

A feasible discrete-time SAC (Simple Adaptive Control) algorithm extended from continuous-time system was proposed for a single-input single-output (SISO) system and removed an offset between a plant output and a reference model output, by inserting parallel feedforward compensators to both of the plant and the reference model. Here, we contrive the design parameters instead of adding the parallel feedforward compensator to the model to remove the above-mentioned offset, and propose a discrete-time SAC algorithm which is feasible and applicable to a multi-input multi-output (MIMO) system. We prove the stability of the system by using asymptotic output tracker theory instead of CGT (Command Generator Tracker) theory, which removes the conventional restriction between the plant and the model.

A Discrete Simple Adaptive Controller and its Application

In this paper, a design method of simple adaptive control(SAC) schemes, is proposed for discrete-time stochastic systems. For discrete-time deterministic systems, a few SAC schemes have been reported. Usually, these methods require a direct control feedthrough as a control block. The existence of the direct control feedthrough, however, makes the SAC schemes complicated. Whereas, according to the proposed control scheme, it enables us to construct further simple adaptive control systems, since it is not necessary to involve the direct control feedthrough in control systems.

Simple Adaptive Control with a Parallel Feedforward Compensator for Processes with Time Delay

Abstract This paper deals with a design problem concerning a simple adaptive control (SAC) system for processes with time delays or higher order lag elements. The SAC method, which is a type of direct model reference adaptive control (MRAC) based on the command generator tracker (CGT) theorem, is fundamentally applicable to plants satisfying the so-called almost strictly positive real (ASPR) condition. Most processes with higher order lag elements do not satisfy the ASPR condition. A design method of a parallel feedforward compensator (PFC) for processes with time delays is derived so that the resulting augmented plant with the PFC, which is virtually regarded as a new controlled plant, will be ASPR. As a result, the SAC can be applied to a broader class of controlled plants including processes with higher order lag elements. The effectiveness of the proposed method is confirmed through a numerical simulation.

Implementation of Simple Adaptive Control Systems by Analog Circuits and a Digital Signal Processor

This paper presents four hardware systems to verify the fundamental principles of continuous-time and discrete-time adaptive systems. Experiments of some simple adaptive systems are easily performed by analog circuits and a digital signal processor. The findings can be incorporated into laboratory-based courses in adaptive control at a senior/graduate level.

Simple Adaptive Control for MIMO Plants with Unmodelled Dynamics and its Application to Processes with Higher Order Lag Elements

Abstract This paper deals with a design problem concerning a simple adaptive control (SAC) system for multi-input/multi-output (MIMO) plants with unmodelled dynamics. The SAC method is fundamentally applicable to plants satisfying the so-called almost strictly positive real (ASPR) condition. The ASPR condition, however, imposes severe restrictions on the plant with regard to practical applications. The design schemes of compensators which make the non-ASPR plant virtually ASPR are proposed by taking plant uncertainties into consideration. As a result, the applicable class of the SAC can be expanded to a broader class of MIMO plants with unmodelled dynamics. The effectiveness of the proposed method is confirmed through a numerical simulation by a process with higher order lag elements.

Motion Control of Robot Manipulators with Decentralized Simple Adaptive Control Scheme and Its Evaluation Using Six-Degree-of-Freedom Manipulator.

A quarter of a century has passed since adaptive control methods were first proposed, but their applications to real robot manipulators have not necessarily been successful. Some reasons are the lack of time for calculation of the adaptive law because of their complexity and the lack of the guidelines for the regulation of the design parameters of the controller. Therefore the evaluation of the methods using real industrial robot manipulators is required in order to confirm the merits and demerits of the adaptive algorithm. In this paper, we consider the motion control problem of robot manipulators with simple adaptive control (SAC) systems and discuss time for calculation and parameter regulation of the method. We used decentralized SAC as an adaptive control algorithm. The simplicity of the adaptive algorithm means that we must regulate a small number of design parameters, and the simplicity of the controller alleviates the shortage of time for calculation. The effectiveness of the method is confirmed through an experiment using a six-degree-of-freedom industrial robot manipulator.