Simultaneous Planning Method Considering Both Overall Configuration and End Pose for Hyper-Redundant Manipulators

Abstract

Featured by extreme flexibility, hyper-redundant manipulators are gradually developed and applied to perform detection and maintenance tasks in confined on-orbit environments. However, its configuration planning is very challenging due to a large number of degrees of freedom. This paper proposes a simultaneous planning method considering both overall configuration and end pose for hyper-redundant manipulators. First, the end effector and intermediate universal joints of the hyper-redundant manipulator are selected as the follow-up controlled points. The corresponding active control points are freely set near the follow-up controlled points. Then, the Euclidean distance between the active control point and the follow-up controlled point is calculated. Combined with gradient projection method, the calculated Euclidean distance is taken as the objective function to be optimized. By adjusting the active control point and the scale factor of gradient projection method, the adjustment of follow-up controlled points (i.e. overall configuration and end pose) can be realized. What is more, this method can optimize its overall configuration to adjust the follow-up controlled points close to or far from the active control point to achieve other planning goals (i.e. obstacle avoidance, singularity avoidance and so on). Therefore, this method satisfies the requirements of simultaneous planning considering both overall configuration and end pose for hyper-redundant manipulators. Finally, the proposed simultaneous planning method is executed in physical experiment system. Results verify the effectiveness of the proposed method.