Manipulation of polygonal objects with two wheeled-tip fingers Planning in the presence of contact position error
This paper addresses the planning problem of object manipulation using wheeled-tip robots considering the wheel-object contact positioning error The term wheeled-lip refers to a new mechanism that incorporates active wheels at robot s fingertips and allows the grasp contact-point to move along the object s surface The benefits of unlimited rolling contact is achieved at the cost of contact positioning error that may cause the manipulation to fail We propose a probabilistic based algorithm for robot motion planning that in addition to being collision free guarantees the stability of the grasp throughout the planned path To do so first we introduce an algorithm that ensures the kinematical stability of the grasp during manipulation by respecting the force closure constraint Further we extend the algorithm to address the practical uncertainties involved in the position of wheel-object contact points The proposed algorithms can be employed for manipulators with limited rolling contacts as well The algorithms have been tested and the results prove that the planned path can be trusted in uncertain situations (C) 2010 Elsevier BV All rights reserved
object manipulation rolling contacts motion planning wheeled tip robots position uncertainty