Planning robotic manipulation strategies for workpieces that slide

Abstract

The authors consider the automated planning of manipulation strategies for workpieces able to slide on their work surface. The aim is to generate open-loop (i.e. sensorless) strategies which succeed in aligning or grasping a workpiece, in the face of two kinds of uncertainty: (1) the initial configuration of the workpiece may have some bounded error, and (2) the details of the contact between workpiece and work surface may be unknown, precluding deterministic solution for the motion of the workpiece even were its initial configuration exactly known. Configuration maps are defined which map all configurations of a workpiece before elementary manipulative operation to all possible outcomes. Using elementary manipulative operations (represented by configuration maps) as primitives, appropriate search techniques are applied to find operations sequences which are guaranteed to succeed despite uncertainty. As a concrete example, the authors demonstrate the automated design of a class of passive parts-feeder consisting of multiple sequential fences across a conveyor belt