Analysis And Synthesis Of Robot Pose Errors

The analysis and synthesis of pose error of robots on the basis of accuracy analysis of rigid robots combining with achievements in research of flexible robots have been studied systematically. Combining accuracy analytical method of rigid robots with kinematics and dynamics, the analytical model of robot pose errors considering influence of robot link and joint flexibility, static error on robot end-effector pose accuracy has been developed. On the basis of established model and Matlab, Windows application is programmed. This software conducts kineto-elastostatic and kineto-elastodynamic analysis for planar and spatial robots consist of N robot links and rotating joints. A conclusion of robot end-pose error resulting from elasto-deformation of robot links, computing robot end-pose error resulting from static error and joint flexibility and robot end-pose error synthesis resulting from many kinds of factors has been drawn eventually. The robot pose error resulting from static errors has been analyzed firstly and the robot static pose error analytic model has been developed. Examples with Stanford robot indicate: angle parameter error influences largely on robot end-pose error. In order to improve robot pose accuracy, robot angle parameter error should be reduce when designing and installing robots. Secondly, by using matrix-structural method and the finite element method, kineto-elasto statics and kineto-elasto dynamics has been analyzed. Then the analytical model of spatial robot end-pose error resulting from robot link flexibility is established. Windows application is programmed on the basis of Matlab. This program is appropriate for planar and spatial robots end-effector pose error resulting from robot links defection. Comparing with documents, the simulation results of planar and spatial robots indicate: the error analytical model is feasible and Windows applied program is valid. Thirdly, all kinds of influencing factors of robot pose error are analyzed. These factors are attributed to robot structural and kinetic parameters. The joint flexibility is included in kinetic parameters. The synthetical influence on robot pose error is given in the example. The results indicate: all kinds of influencing factors on robot end-pose are included in this method. Finally, by using the kinematical programming, the compensation of robot end-pose errors resulting from various factors is studied. The simulation demonstrates that the proposed method can improve the accuracy of the robot trajectory tracking.