Research On Adaptive Control Technology Of Electromagnetic Centerless Fixture

In the manufacturing industry,as a key basic component.And its processing quality affects the working performance of the equipment to a great extent.The output of bearings in China is in the forefront of the world,but it accounts for a small proportion in the high-performance bearing market.At present,most of the bearings used in highperformance equipment in China still rely on imports,which shows that there is a big gap between China and the international advanced manufacturing level in the field of bearing manufacturing.The export of high-performance bearings to China is strictly restricted abroad.In order to solve the “neck strangled” problem of high-performance bearing manufacturing technology,it is urgent to improve China’s bearing manufacturing level.When centerless grinding is carried out on a grinder with electromagnetic centerless fixture,the conventional electromagnetic centerless fixture is difficult to adapt to the complex and changeable grinding force.It is easy to produce vibration in the grinding process,which is one of the reasons why the processing quality can not meet the requirements of high-performance bearings,and the ring is easy to produce deformation,scratches.The research on the adaptive control technology of electromagnetic centerless fixture has practical application value.In this paper,the adaptive control technology of electromagnetic centerless fixture was studied in order to adaptively control the radial clamping force and improve the machining quality of rings.1.The hardware and structure design of adaptive electromagnetic centerless fixture were carried out.Through the force analysis of electromagnetic centerless grinding ring,the control scheme was determined.According to the structure and characteristics of electromagnetic centerless fixture,the selection of pressure sensor,signal transmitter,PLC controller,switching power supply and solidstate relay was carried out.And the new support,iron core,magnetic pole,clamp and coil structure of the adaptive control system of electromagnetic centerless fixture was designed.2.The control strategy of adaptive control system for electromagnetic centerless fixture was studied and formulated.The mathematical model was analyzed and established,the fuzzy adaptive controller was designed,and the comparative simulation of PID controller and fuzzy adaptive PID controller was carried out.It was proved that compared with PID controller,fuzzy adaptive PID controller had faster response speed and better robustness.3.The software of control system was designed.The distribution address table,fuzzy controller ladder diagram,query fuzzy control decision table ladder diagram,PID control and PWM output ladder diagram of PLC were designed,and the upper computer monitoring system based on MCGS configuration software was designed.4.The external groove grinding test was carried out.The results show that the fuzzy adaptive PID controller could achieve better control effect in the electromagnetic centerless fixture control system.The experiment proved that the error of the electromagnetic fixture could be reduced to a certain extent.