Friction Model Parameter Identification Based On Genetic Algorithm Research

Friction is an impediment to improve the control accuracy of servo systems,before to achieve low-velocity and high precision control, we must compensate thefriction exist in the system. Model-based friction compensation is more pertinency.Generally, this method can achieve good control effect if we can gain an exactfriction model of the system. Parameters identification of friction model is the mainissue of this dissertation.The present research work of parameters identification of friction model athome and abroad is summarized firstly. After analyze and compare these methods, Aparameter identification method of friction model with Generic Algorithms is putforward.Then this dissertation analyzed the creation theory of friction, the dynamicphenomenon of friction, the friction phenomenon in servo sysytems and somestatic/dynamic friction models which are commonly used. Via analyze and compareof the characteristics of these models, I choose the "Coulomb&Viscous model" and"Tustin model" as the identification objects. I choose a two rank system as thecontrol system, a random distubance was plus to this system to simulate the frictionphenomenon in servo system, and use the Generitc Algorithms to identify theparameters of the "Coulomb&Viscous model" and "Tustin model". These are carriedout by some Maflab programs.Finally, using the Matlab/Simulink, a model-based "PID+feedforward" frictioncompensation method is carried out, and proved this parameter identificationmethod based on the Genetic Algorithms is effective.