Perception, Control and Hardware for In-Hand Slip-Aware Object Manipulation with Parallel Grippers

Abstract

Dexterous in-hand manipulation offers significant potential to enhance robotic manipulator capabilities. This paper presents a sensori-motor architecture for in-hand slip-aware control, being embodied in a sensorized gripper. The gripper in our architecture features rapid closed-loop, low-level force control, and is equipped with sensors capable of independently measuring contact forces and sliding velocities. Our system can quickly estimate essential object properties during pick-up using only in-hand sensing, without relying on prior object information. We introduce four distinct slippage controllers: gravity-assisted trajectory following for both rotational and linear slippage, a hinge controller that maintains the object's orientation while the gripper rotates, and a slip-avoidance controller. The gripper is mounted on a robot arm and validated through extensive experiments involving a diverse range of objects, demonstrating the architecture's novel capabilities for manipulating objects with flat surfaces.