Experimental Study on Low Velocity Friction Compensation and Tracking Control
نویسندگان
چکیده
Stick-slip phenomenon is often associated with the control of low velocity motion because of the positional dependancy of friction and negative damping friction that decreases as the motion speed increases. In this paper, smooth low velocity tracking control of a commercial robot joint is demonstrated experimentally using a combination of high gain PID control, fast sampling rate and high position sensor resolution. The experimental results also reveal that the main source of instability is not negative damping friction, but position dependant friction that has been widely neglected. The short sampling period and a high resolution encoder have allowed us to compensate for the position dependant friction with a PID controller with sufficiently high gains.
منابع مشابه
Identification and Model-based Compensation of Striebeck Friction1
The paper deals with the measurement, identification and compensation of low velocity friction in positioning systems. The introduced algorithms are based on a linearized friction model, which can easily be introduced in tracking control algorithms. The developed friction measurement and compensation methods can be implemented in simple industrial controller architectures, such as microcontroll...
متن کاملFriction Compensation in Servo Systems Using a Local Control Design Approach
Nonlinearities degrade considerably performances in motion control systems. Nonlinear friction is a major source of many serious problems such as wear, tracking errors and limit cycles. There has been an extensive research activity dealing with the design of compensating techniques. The approaches cited in the litterature can be divided into: free model compensation or model based compensation ...
متن کاملPeriodic Adaptive Compensation of State-dependent Disturbance in a Digital Servo Motor System
This paper presents an adaptive controller for the compensation of state-dependent disturbance with unknown amplitude in a digital servo motor system. The state-dependent disturbance is caused by friction and eccentricity between the wheel axis and the motor driver of a mobile robot servo system. The proposed control scheme guarantees an asymptotical stability for both the velocity and position...
متن کاملOn Methods for Low Velocity Friction Compensation: Theory and Experimental Study
A study of diierent classes of controllers for mechanisms under the innuence of low velocity friction is conducted. Many methods are proposed in the literature for friction compensation, but there has been no signiicant analysis of these methods with respect to each other. Also lacking in the literature is some form of categorization, under which it is possible to describe and study their perfo...
متن کاملControl of the Electro-pneumatic VGT Actuator with Friction Compensators
This paper describes friction compensation based control of an industrial pneumatic actuator used for the variable geometry turbocharger (VGT). Adaptive LuGre model for friction has been used in this work. Friction force that is responsible for hysteresis and hunting phenomenon in the position control is compensated with two different control strategies designed to improve low velocity position...
متن کامل