A novel inverse kinematics method for 6-DOF robots with non-spherical wrist

A novel numerical method is proposed to solve the inverse kinematics for 6-DOF robots with non-spherical wrist in this paper, which firstly simplifies the non-spherical wrist structure to a spherical one. In each iteration of the algorithm, the inverse solution of simplified robot is firstly used to calculate the end pose of actual robot to estimate the end position error between the calculated end pose and the target pose. And then the inverse solution of simplified robot gradually approaches the desired solution by compensating for the end position error. Additionally, the failure of proposed method caused by the reduction of robot workspace due to structure simplification is analyzed and then the offsetting of known end pose is introduced to improve the robustness of algorithm. Finally, numerical experiments for two typical robots prove the effectiveness of proposed method; a comparative study shows the advantages of proposed algorithm over Newton-Raphson (NR) algorithm; and the performance in processing continuous trajectories demonstrates its good practicability. (C) 2020 Elsevier Ltd. All rights reserved.

Automated summary

A novel numerical method is proposed to solve the inverse kinematics for 6-DOF robots with non-spherical wrist by simplifying the wrist structure and gradually approaching the desired solution. The method's effectiveness and practicality are demonstrated through numerical experiments, comparative studies, and performance in processing continuous trajectories.