Picking by Tilting: In-Hand Manipulation for Object Picking using Effector with Curved Form

TL;DR

This paper introduces a novel in-hand manipulation method that uses tilting and passive end-effectors to pick large objects, demonstrating reliable performance with simple hardware across various object sizes and shapes.

Contribution

The paper proposes a new tilting-based in-hand manipulation technique utilizing curved passive end-effectors and flat supports, enabling object picking beyond traditional grasping methods.

Findings

Successful object picking demonstrated on various sizes and geometries

Reliable performance with simple hardware and control strategies

Effective tilting strategy enhances grasping capabilities

Abstract

This paper presents a robotic in-hand manipulation technique that can be applied to pick an object too large to grasp in a prehensile manner, by taking advantage of its contact interactions with a curved, passive end-effector, and two flat support surfaces. First, the object is tilted up while being held between the end-effector and the supports. Then, the end-effector is tucked into the gap underneath the object, which is formed by tilting, in order to obtain a grasp against gravity. In this paper, we first examine the mechanics of tilting to understand the different ways in which the object can be initially tilted. We then present a strategy to tilt up the object in a secure manner. Finally, we demonstrate successful picking of objects of various size and geometry using our technique through a set of experiments performed with a custom-made robotic device and a conventional robot arm. Our experiment results show that object picking can be performed reliably with our method using simple hardware and control, and when possible, with appropriate fixture design.