Industrial Robot Kinematic Calibration Based On Spatial Correlation

As China's manufacturing 2025 release,the research of industrial robot technology and application in aerospace equipment manufacturing is an effective method for response to the national manufacturing strategy.However,the current situation of the industrial robot with low absolute positioning accuracy is as a deterrent to its application and development.So,delve into the kinematic calibration technique is the key to ensure of industrial robots be used in aerospace equipment successfully.In view of the limited effect of traditional calibration method based on kinematic model,the concept of residual error spatial correlation is proposed.And put forward a kind of positioning error and the residual error compensation method based on parameter identification and spatial correlation.Drastically reduce the residual error and enhance the absolute positioning accuracy of the robot.The article's main research content is as follows:(1)Model the robot kinematics by D-H model and analysis forward and inverse kinematic.Established robot kinematic error model which contains established error of the base coordinate system and error of geometric parameter.(2)Studied the basic principle of parameter identification and specific iterative process of the L-M algorithm.The concept of residual error spatial correlation is proposed and which is proved by qualitative analysis and semivariogram.(3)Adopt a regression model to establish the relationship between residual error and theoretical position.Set up the spatial correlation model between the target and the sampling points.And use a linear unbiased optimal estimation method for the estimate of target residual error.Put forward a method of positioning error and residual error compensation based on parameter identification and spatial correlation.(4)In order to verify the proposed method of positioning and residual error compensation,an experiment is conducted.Comprehensive maximum absolute positioning error reduce to 0.3209 mm after positioning error compensation from 1.4920 mm,after the residual error compensation reduce to 0.2768 mm,which reduced by 81.45%.It is prove that this method can compensate the robot residual errors effectively.