The Wrist Structure And Kinematics Analysis Of A 6 DOF Robot

With the development of light mechanical and electrical integration technologies, industrial robotics has been widely applicated in many fields. In order to use robots technologies better, improve their performance, under the virtual assembly lines, the wrist structure and kinematics has been researched in this thesis of a general PUMA assembly robot.The research in this thesis based on U.S Unimation manufactured PUMA series 6-DOF general assembly robot analysis. The main contact include that analysis of the manipulator's structural characteristics, the established of a 3-DOF spherical wrist transmission model, and analysed its structure characteristics, established the kinematics,dynamics equation, and also the kinematics,inverse kinematics of the whole arm was solved. More importantly, there was the derived motion of wrist motion were analyzed, and studied the compensation algorithm. According to wrist structural characteristics, analyzed its transmission chain transmission principle, furtherly induced the compensated methods, so robot joints angle of wrist can be modified, when the wrist motors drived in the same time. Through Matlab and Simulink software simulated, acquired the accurate end-effector trajectory.In order to meet the assembly robot trajectory tracking accuracy and precision requirements, this thesis established the structure of the whole arm model and wrist transmission model, used Solidworks 3D CAD mechanical design software to design structure, and according the characteristics of transmission structure and driving principle, raised the derived motion question of wrist. On this basis, then the three motor drived in the same time, further analysis have been done with the wrists of each other. Analysis showed that,because of different transmission structure, derived movement influenced the extent and results were different.Then, analyzed the simulation results with the two different conditions. First, the derived movement of the wrist were not considered; second, the wrist derived motion were considered, carried out the distinction between the end of the actuator trajectory, reflected the significant influences of assembly robot wrist derived motion to assemble accuracy. This thesis according the established kinematics and dynamics equations, to do mechanical dynamics simulation whith Simulink software, and with joint values of the derived movement compensation to simulate end-effector trajectory. The simulation results can be useful to the practical application of robots and provided theoretical backgrounds and supports.