Open-loop controller

About: Open-loop controller is a research topic. Over the lifetime, 16148 publications have been published within this topic receiving 224014 citations. The topic is also known as: non-feedback controller & open-loop control law.

PSO-based Motion Fuzzy Controller Design for Mobile Robots

Abstract: A motion control structure with a distance fuzzy controller and an angle fuzzy controller is proposed to determine velocities of the left-wheeled motor and right-wheeled motor of the two-wheeled mobile robot. A PSO-based method is proposed to automatically determine appropriate membership functions of these two fuzzy systems so that the controlled robot can move to any desired position effectively in a two-dimensional space. A ratio coefficient coding method and a variable fitness function are considered in the proposed PSO-based fuzzy controller design method so that the proposed PSO-based method with a good searching efficiency and the selected fuzzy controller with a good control performance.

A PLC-based modified-fuzzy controller for PWM-driven induction motor drive with constant V/Hz ratio control

Abstract: In this paper, a method to develop and design a fuzzy-hybrid control on an industrial controller to control speed of an induction motor and implementing a constant V/Hz ratio control is presented. Detailed discussions on the controller for a PWM-driven induction motor drive system, the system identification for the model transfer function, and the analysis on output responses and the associated manipulated variables are presented. The control objective is to provide an effective control action to sudden changes in reference speed and/or load torque. A switching type controller consisting of two control modes are devised: a PID-type fuzzy controller consisting of a PI-type and a PD-type fuzzy controller, and a conventional PID. At the early phase of the control action, the control task is handled by the PID-type fuzzy controller. At a later phase when the absolute of error is less than a threshold value, the input of integrator at the output side is no longer given by fuzzy action but fed by the incremental PID action. In term of control action, this is an enhanced proportional and derivative action when the actual value is closed to reference. Detailed evaluations of the controller's performance based on pre-defined performance indices under several conditions are presented. The findings demonstrate the ability of the control approach to provide a viable control solution in response to the different operating conditions and requirements.

Design and Validation of a Gain-Scheduled Controller for the Electronic Throttle Body in Ride-by-Wire Racing Motorcycles

Abstract: This paper presents the analysis, design and validation of a gain-scheduled controller for an electronic throttle body (ETB) designed for ride-by-wire applications in racing motorcycles. Specifically, the open-loop dynamics of the system are studied in detail discussing the effects of friction based on appropriate experiments. Further, a linear time invariant nominal model of the system to be controlled is experimentally identified via a frequency-domain black box approach, together with the uncertainty bounds on the model parameters. Based on these results a model-based gain-scheduled proportional-integral-differential (PID) controller for throttle position tracking is proposed. The closed-loop stability of the resulting linear parametrically varying (LPV) system is proved by checking the feasibility of an appropriate linear matrix inequality (LMI) problem, and the state space representation of the closed-loop LPV system is experimentally validated. Finally, the performance of the controlled system is compared to the intrinsic limit of the actuator and tested under realistic use, namely both on a test-bench employing as set-point the throttle position recorded during test-track experiments and on an instrumented motorcycle.

Setpoint weighted PID controller tuning for unstable system using heuristic algorithm

Abstract: Most of the real time chemical process loops are unstable in nature and designing a suitable controller for such systems are difficult than open loop stable processes. In this work, an attempt is made with a two degree of freedom setpoint weighted PID controller tuning procedure for a class of unstable systems using the recent heuristic algorithms such as Particle Swarm Optimization and Bacterial Foraging Optimization. The problem considered in this study is to aptly tune the controller in order to enhance the overall closed loop performance. A novel objective function proposed in this study is used to monitor the heuristic algorithms in order to get the optimal controller parameters like Kp, Ki, Kd , and α with minimized iteration number. The proposed method is validated with a simulation study and this helps to accomplish enhanced system performance such as smooth reference tracking, satisfactory disturbance rejection, and error minimization for a class of unstable systems.

Method of implementing a linear discrete-time state-space servo control system on a fixed-point digital signal processor in a disc drive

Abstract: A method of implementing a model based servo controller in a digital signal processor in a disc drive includes obtaining matrices for a discrete-time state-space realization of the servo controller. Controller states of the controller are scaled to reduce a worst case bound on the controller states. The controller states are transformed to a desired format which reduces a number of required mathematical operations. Further, the matrices are converted to fixed point format.