A Hand Combining Two Simple Grippers to Pick up and Arrange Objects for Assembly

TL;DR

This paper introduces a low-cost robotic hand combining two simple grippers for precise object alignment, picking, and arranging in assembly tasks, reducing complexity and cost compared to traditional designs.

Contribution

A novel robotic hand design that integrates two simple grippers for efficient assembly, eliminating the need for complex mechanisms or control strategies.

Findings

Effective alignment and handling of small objects like screws and washers.

Successful validation through real-world experiments and quantitative analysis.

Reduced cost and complexity compared to conventional robotic hands.

Abstract

This paper proposes a novel robotic hand design for assembly tasks. The idea is to combine two simple grippers -- an inner gripper which is used for precise alignment, and an outer gripper which is used for stable holding. Conventional robotic hands require complicated compliant mechanisms or complicated control strategy and force sensing to conduct assemble tasks, which makes them costly and difficult to pick and arrange small objects like screws or washers. Compared to the conventional hands, the proposed design provides a low-cost solution for aligning, picking up, and arranging various objects by taking advantages of the geometric constraints of the positioning fingers and gravity. It is able to deal with small screws and washers, and eliminate the position errors of cylindrical objects or objects with cylindrical holes. In the experiments, both real-world tasks and quantitative analysis are performed to validate the aligning, picking, and arrangements abilities of the design.