An Attempt to Raise the Level of Software Abstraction in Assembly Robotics through an Apposite Choice of Underlying Mechatronics

Robot manipulators were meant to be the production engineer"s flexible friend. Assembly robots, however, have failed to fulfill their promise. The problem that has continuously plagued robotic assembly is that of spatial uncertainty. It is our thesis that the ubiquitous problem of spatial uncertainty is an artefact of the fact that current industrial manipulators are designed for an operational paradigm that assumes position control is of primary importance. In this paper we propound an alternative approach based on sliding as the primary motion primitive. We first present a model that uses sliding to allow us to raise the level of abstraction of robot programming tasks. We then describe an inherently accommodating, (planar) three degree of freedom, direct-drive robot arm that was constructed to test our approach. Finally, we present data collected from representative (planar) manipulation tasks that substantiate our claims.