Study On Control Theory For Giant Magnetostrictive Actuator Cutting Machining

With the rapid development of aerospace,automobile,biomedicine,machine tools and other industries,non circular parts are more and more widely used in these fields.In the method of forming non circular parts,the turning technology has the advantages of good processing efficiency and high precision compared with other methods.Therefore,in the industrial field,especially for the processing of non-circular parts,it is a cutting method that can meet the industrial needs.Selection of giant magnetostrictive non circular surface precision machining tool is started,to solve the shortcomings of the traditional hard profiling method,well done without phantom for high precision automatic processing.The lathe driven system driven by GMA has the advantages of simple and strict structure,high repetition and precision,no separation,hard and no deformation,little inertia and continuous and stable working.However,due to the obvious hysteresis nonlinearity between the external magnetic field and the output displacement of the giant magnetostrictive actuator,the control effect of the system will be affected.In order to solve this problem,this paper chooses the turning system of giant magnetostrictive actuator as the research object,and carries out the following research:(1)This paper introduces the research status of the driving way and the control method of the super magnetic telescopic actuator for non-circular part turning,and introduces the hysteresis model briefly.Then,based on the Jiles-Atherton model,we establish the GMA dynamic model.Then the turning force is introduced,and the dynamic model of the GMA driven turning system is established.Using the Simulink simulation tool in MATLAB,the model is verified by simulation,and the feasibility of the model is verified by the simulation results.(2)Taking GMA turning system dynamic model as control object,fuzzy PID controller is designed according to fuzzy control principle,and compared with general PID controller to verify its superiority.The interference signal is added at the end,and the better self adjustment ability of the fuzzy PID controller is verified by simulation.(3)Considering the nonlinear hysteresis causes errors exist in giant magnetostrictive actuator system,so to solve this problem,the design of a RBF neural network inverse controller is used as feedforward controller and fuzzy PID controller as a feedback controller,the combination of displacement characteristic experiment by MATLAB simulation,the experimental results show that the control method this can effectively improve the magnetostrictive actuator control accuracy of system.