Study On Coupling Dynamic Characteristics And Vibration Control Of Elastic Thin-Walled Parts Grinding System

Elastic thin-walled parts have the advantages of light weight and high strength ratio,and are widely used in automobile,wind power blade,aerospace and other fields.Grinding is an important link in the processing of elastic thin-walled parts.Due to the low stiffness and large deflection of elastic thin-walled parts,it is easy to produce deformation and chatter during grinding.At the same time,the grinding spindle is a typical electromechanical coupling system,which is sensitive to the elastic vibration of elastic thin-walled parts.Therefore,it is important to study the coupling dynamic characteristics and vibration control of elastic thinwalled grinding system.The research work of this paper mainly includes:(1)According to the coupling relationship between elastic thin-walled parts and grinding spindle,the electromechanical coupling dynamics model of grinding spindle and elastic thin-walled parts dynamics model were constructed based on Lagrange-Maxwell equation and mode superposition,etc.The mechanical and electrical coupling dynamics model of the grinding spindle and the dynamic model of the elastic thin-walled parts were constructed.The coupling dynamics model of the elastic thinwalled parts-grinding spindle system was obtained by combining the grinding force empirical formula.Based on this,the coupling dynamics simulation model of the coupling system was built.The output characteristics of grinding spindle under vibration coupling of elastic thinwalled parts were analyzed by numerical simulation.(2)The dynamic model of the grinding system of elastic thin-walled parts under elastic boundary constraints was established.The displacement function of elastic thin-walled parts was described by the improved Fourier series,and the unified vibration equation of elastic thin-walled parts under elastic boundary constraints was established by the energy method.The model was solved based on the Rayley-Ritz method.The natural frequencies and modes of vibration of elastic thin-walled parts under different boundary conditions are analyzed.On this basis,combined with the coupling dynamics model of grinding system,the dynamic model of coupling system of elastic thin-wall parts-grinding spindle under elastic boundary constraints was established,and the modal characteristics of elastic thin-wall parts and the dynamic characteristics of coupling system under elastic boundary constraints were analyzed.(3)The vibration control strategy of elastic thin-wall grinding system based on speed adaptation is studied,and the simulation model of speed adaptive control system and co-simulation virtual prototype model of elastic thin-wall grinding system were established.Simulation analysis and virtual prototype experiment results show that the designed speed adaptive control system of grinding system can realize grinding spindle speed disturbance control and vibration suppression of elastic thin-walled parts under vibration coupling.On this basis,an adaptive speed control system of elastic thin-walled parts grinding system based on stiffness identification is constructed.The system can realize the vibration control of grinding spindle speed and the vibration suppression of elastic thin-walled parts under the constraint of elastic boundary.(4)Based on analysis of dynamic characteristics of elastic thin-walled parts grinding system,an electromagnetic device for vibration suppression of elastic thin-wall grinding system was designed,and active vibration control strategy of elastic thin-wall grinding system was studied,electromagnetic vibration suppression device physical prototype was developed and built elastic thin-walled grinding system vibration control experiment platform,elastic thin-walled grinding system vibration control experiment was carried out,The effectiveness of active vibration control strategy of elastic thin-walled grinding system was verified.