Title :
New strategies for avoiding robot joint limits: Application to visual servoing using a large projection operator
Author :
Marey, Mohammed ; Chaumette, François
Author_Institution :
Centre Rennes-Bretagne Atlantique, IRISA, Rennes, France
Abstract :
In this paper, we present a new redundancy-based strategy for avoiding joint limits of a robot arm. This strategy is based on defining three functions for each joint: an activation function; an adaptive gain function; and a tuning function. These functions allow determining automatically the required sign and the suitable magnitude for the avoidance process at each joint. The problem of adding an additional task with the main task and the avoidance process is also considered and solved. As for the redundancy framework, a new large projection operator based on the norm of the usual error is used to enlarge the redundancy domain for applying our proposed avoidance strategy. The experimental results obtained on a 6 dof robot arm in eye-in hand visual servoing show that the new avoidance strategy gives smooth joint avoidance behavior without any tuning step. Using the new projection operator allows a significant improvement of the joint avoidance process, especially in the case of a full rank task function.
Keywords :
collision avoidance; redundancy; redundant manipulators; visual servoing; activation function; adaptive gain function; avoidance strategy; eye-in hand visual servoing; full rank task function; joint avoidance process; large projection operator; redundancy-based strategy; robot arm; robot joint; smooth joint avoidance behavior; tuning function; visual servoing;
Conference_Titel :
Intelligent Robots and Systems (IROS), 2010 IEEE/RSJ International Conference on
Conference_Location :
Taipei
Print_ISBN :
978-1-4244-6674-0
DOI :
10.1109/IROS.2010.5653044