Kinematics of a 6-DOF Feeding and Unloading Manipulator

Abstract

In order to improve the efficiency of kinematics modeling in analyzing robots, this document used Lie groups and screw theory to describe rigid motion of the robot system, established a kinematic model of operating arm based on Product of Exponentials (POE) formula, and analyzed forward and inverse kinematics of chain topology structure robot, as well as several sub-inverse problem of inverse kinematics. A 6-DOF series-wound configuration loading and unloading manipulator has been used as an example, its kinematics equations are established by POE formula combined with screw theory, the special configuration of end effector under a specific task planning are calculated using Mathematica software. By contrast with D-H parameters method, we can draw a conclusion that POE formula and D-H parameters method are essentially equivalent. However, POE formula and motion screw have more definite geometric and physical meaning, neat expression form, convenient algebraic operation, are able to overcome limitations, such as calculation complexity and singularity in solving process, can meet kinematic analysis and real-time control of robot.