Robot task specification and execution through relational positioning

Abstract

This paper presents a relational positioning methodology for flexibly and intuitively specifying offline programmed robot tasks, and for assisting the execution of teleoperated tasks featuring precise or repetitive movements. By formulating an object positioning problem in terms of symbolic geometric constraints, the movements of an object can be restricted totally or partially, independently of its initial configuration. To solve the problem, a 3D sequential geometric constraint solver called PMF –Positioning Mobile with respect to Fixed– has been developed. PMF exploits the fact that in geometric constraint sets the rotational component can often be decoupled from the translational one and solved independently.