Positioning Error Analysis And Compensation Experiment Of Eccentric Drive Feeding System

As the core system of high-end equipment including NC machine tools and industrial robots,feeding system can directly determines the whole performance and accuracy of the equipment.In ball screw feeding system,in order to avoid the eccentric torque and realize Driven at Center of Gravity,the driving force of motor is generally acted on the centroid of moving parts.However,in the actual design,due to structural constraints and economic costs,it is inevitable that the motor should be arranged in the eccentric position that is named eccentric drive feeding system.In the eccentric drive feeding system,since the driving force of the motor does not pass through the center of mass,eccentric moment will be generated during the running process,which puts the feeding device into an adverse condition.Vibration intensification,deformation,and tilt,would affect the positioning precision of eccentric drive feeding system.In this paper,aiming at improving the positioning error in eccentric drive feeding system,the eccentric drive feeding experimental table is considered as the research object,and the potential influence factors of the positioning error,measurement and analysis of the positioning error and compensation experiments are studied.Specific research contents are listed as follows:(1)The model of the eccentric drive feeding mechanical system was established,and the main influence factors of the positioning error of eccentric drive feeding system were analyzed.The influence of the positioning error of eccentric drive feeding system was studied by changing parameters in the model,and the simulation analysis was carried out.(2)The positioning error measurement scheme of eccentric drive feeding system was designed to analyze the variation law among positioning error and position and speed.The positioning error modeling method of the orthogonal polynomial and Newton interpolation was used to establish the mathematical model of the positioning error of eccentric drive feeding system.(3)Built the eccentric drive feeding experiment table system.The design of electrical system of the experimental table was completed,and the full-closed loop control system of the experimental table was built.The full-featured and interactionfriendly control software was developed by the method of modularization.In order to improve the control performance of the feeding system,the debugging of eccentric drive feeding system was completed.Control system was tuned by adjusting PID and other parameters.(4)The error compensation method based on the virtual-axis and the piecewise error compensation strategy were adopted for the eccentric drive feeding system,and the compensation principle was analyzed.The program of positioning error segmentation compensation for eccentric drive feeding system was completed.Combined with the mathematical model of positioning error,the error compensation of eccentric drive feeding experimental table was carried out,and the compensation effect is analyzed.