Comparative Peg-in-Hole Testing of a Force-Based Manipulation Controlled Robotic Hand.

Abstract

Force-based manipulation control strategies are evolving as a primary mechanism in robotics for performing the fine manipulation tasks typical within manufacturing assembly. The ability to systematically compare robotic system performance and quantify true advancement in fine manipulation is of utmost importance. Accordingly, the objectives of this paper are threefold: 1) creation of a peg-in-hole test method with associated performance metrics and a systematic data analysis strategy for performance benchmarking, 2) first demonstration of a recently developed manipulation controller piloting a robotic hand and its paired task-level logic for completing the peg-in-hole test, and 3) exemplifying the performance benchmarking technique by comparing two approaches for robotic insertions-the previously mentioned compliant hand, stiff arm system, and a stiff gripper, compliant arm system. Analyses reveal that the unconventional hand system can perform at and sometimes above the level of the gripper system in the developed peg-in-hole scenario. Moreover, the hand's active control of the peg's full Cartesian pose reduces positional error sensitivity and minimizes exerted insertion forces, highlighting the strategy's potential for fine manipulation tasks. Results indicate that robotic arms equipped with highly articulated and sensorized robotic hands can provide a truly realizable solution path for performing peg-in-hole tasks.