Clamping weighted least-norm method for the manipulator kinematic control with constraints. Issue 11 (1st November 2016)

• Record Type: Journal Article
• Authors: Huang, Shuihua; Peng, Yonggang; Wei, Wei; Xiang, Ji
• Is Part Of: International journal of control. Volume 89:Issue 11(2016)
• Page Start: 2240
• Page End: 2249
• Publication Date: 2016-11-01
• Subjects: Clamping weighted least-norm method -- inverse kinematic control -- joint limit -- manipulator; Automatic control -- Periodicals; Electronic journals; 629.8
• DOI: 10.1080/00207179.2016.1153151
• Languages: English
• ISSNs: 0020-7179

Abstract

ABSTRACT: One of the main challenges for kinematic control of manipulators is how to effectively address various constraints, such as obstacle avoidances. Most constraints can be converted into a virtual joint-limit problem by the general weighted least-norm method reported recently. However, a chattering of weighted factors might occur in the presence of disturbances. In this paper, in order to improve the robustness to disturbances, a clamping term forcing joints away from their limits is added to the solution of inverse kinematics, termed as the clamping weighted least-norm method. It is proved that the joint-limit constraint is always guaranteed. The proposed method is applicable to both non-redundant and redundant manipulators; the accuracy of main task is sacrificed only when there is confliction between main task and joint-limit constraint. Experiments on the seven-degree-of-freedom redundant manipulator illustrate the good performance for avoiding joint limits while tracking a given trajectory.