On Active Disturbance Rejection Control Strategy Of Macro-micro Compound Motion Platform

The development of microelectronic manufacturing equipment technology is related to the development of national economy,which is the comprehensive embodiment of China's advanced manufacturing capacity and scientific and technological development level.With the rapid development of microelectronic packaging technology,micro-nano processing technology and other fields and huge market demand.Its core component-precision motion platform,is facing high acceleration,high speed,high precision,large itinerary and other difficulties,Macro-micro composite motion platform is becoming an important development direction to solve this problem.Friction is the main reason that affects the positioning accuracy of the mechanical guide motion platform,and the macro micro composite motion platform combines the frictionless flexible hinge with the linear motion platform to compensate the friction dead zone by using the elastic deformation of the flexible hinge.However,the natural frequency of flexible hinge is low,its nonlinear elastic vibration seriously affects the steady state performance of micro-platform.In this paper,ADRC of macros-micro composite dualdrive platform is studied by comprehensive analysis from the point of view of the mechanism principle and control system design of macro-micro composite motion platform.First of all,this paper introduces the composition of macro micro composite motion platform.The basic structure and working principle of three-phase PMSLM are analyzed,and its mathematical model is established.On the basis of coordinate transformation,the working principle and implementation scheme of space vector control are studied.The mechanism principle of macro micro composite mechanical platform is analyzed and its mathematical model is established.For non-friction micro-platform,the nonlinear elastic vibration problem of flexible hinge is the main reason that affects its positioning accuracy.At the same time,according to the structure characteristics of macro micro-composite motion platform,its control scheme is determined.Therefore,the key research problems in this paper are determined,which makes theoretical paving for the application of the subsequent ADRC technology.Secondly,this paper introduces the basic principle of PID control and ADRC algorithm,and introduces the nonlinear and linearized structure of ADRC technology in detail.By setting up a simple simulation model,the parameter finishing principle of LADRC is summarized and analyzed.The simulation results verify the superiority of LADRC in parameter setting.Then,according to the above two parts,this paper designs the ADRC strategy of macro micro-composite motion platform.For macro platform,a double closed-loop servo system based on PID control algorithm is designed as a macro platform control strategy,and its parameter tuning method is studied.The macro platform compensates the influence caused by the nonlinear friction of the mechanical guide through the macro micro-two-stage drive mode.The visual elastic vibration is disturbance for micro platform,which the difficulty of establishing nonlinear elastic vibration precision mathematical model is avoided.The nonlinear elastic vibration and platform uncertainty of flexible hinge are estimated actively by the expansion state observer and compensating at position loop of micro-position,so as to ensure the positioning accuracy of micro platform.On the basis of space vector control technology,the simulation model of macro-micro composite motion platform is built.The step response experiment shows that the LADRC response time is shortened by 20.58% and the dynamic performance of the system is improved effectively compared with the PID algorithm.The anti-constant disturbance experiment shows that the LADRC fluctuation amplitude is smaller and can enter the steady state more quickly.Finally,on the basis of theoretical research,this paper builds a macro-micro composite motion experimental platform.The performance of single-stage drive rigid platform and macro-micro composite two-stage drive platform is compared,and the macro-micro composite motion platform based on LADRC technology is verified by step response experiment,point to point motion disturbance experiment and sinusoidal tracking experiment with good anti-disturbance performance and tracking performance.