Implementation And Friction Compensation For Servo Systems

The core of the turntable control technology is the controller design and implementation.As the development of electronic technology and manufacturing process, control performance of servo control system is becoming more and more high.At present, the digital controller based on ARM, DSP, FPGA has a wide range of applications in the turntable control system.These digital controllers generally have abundant peripheral interface, can carry out complex operations, can adapt to the requirements of the turntable control system.Based on TMS320F28335 of TI company as the core controller, this article has carried on the turntable controller design and implementation, and studied the friction compensation problem.This article first to analyze the mathematical model of the test turntable, and introduces the hardware of the system as a whole.Controller hardware circuit design, mainly including controller and drive, the controller is based on TMS320F28335, mainly complete the reading out of encoder signal, and communicating with master computer, putting out PWM signal, and so on.driver using bipolar PWM drive H bridge.Software design and implementation of the controller, using e QEP module to measure the speed and position of the turntable, using e PWM module to generate PWM drive signal, using SCI module to communicate with controller and master computer.Measuring the rotational speed of turntable, compares the characteristics and application scope of the measuring methods of T method and M method.The software design of master computer, mainly considering the real-time and transmission error.In order to observe the results expediently, design the PC interface by Matlab GUI, we can obverse the condition and transport the control instructions by the PC interface real-timely.Usually, the high precision servo turntable working with a low speed, friction interference can cause great influence to the accuracy of turntable.In this paper, the friction compensation problem is studied.There are some common friction model, such as the viscous friction model, the Stribeck friction model, the Lu Gre friction model, and so on.Considering the complexity of the dynamic friction model, this paper use the classical viscous friction model to simulate the friction torque, choosing feedforward and PID algorithm to compensate friction interference.Simulation and real test show that the hybrid control strategy has inhibitory effect on friction interference...