Designing and Validating a Self-Aligning Tool Changer for Modular Reconfigurable Manipulation Robots

TL;DR

This paper introduces a self-aligning tool-changing mechanism for modular robots that compensates for misalignments, enabling reliable autonomous module exchange without complex sensors.

Contribution

It presents a novel hardware design with passive self-alignment geometries and an integrated exchange station, improving robustness and autonomy in reconfigurable robots.

Findings

Successfully absorbs positioning errors during tool exchange

Enables autonomous and reliable module reconfiguration

Validated through real-world robotic experiments

Abstract

Modular reconfigurable robots require reliable mechanisms for automated module exchange, but conventional rigid active couplings often fail due to inevitable positioning and orientational errors. To address this, we propose a misalignment-tolerant tool-changing system. The hardware features a motor-driven coupling utilizing passive self-alignment geometries, specifically chamfered receptacles and triangular lead-in guides, to robustly compensate for angular and lateral misalignments without complex force sensors. To make this autonomous exchange practically feasible, the mechanism is complemented by a compact rotating tool exchange station for efficient module storage. Real-world autonomous tool-picking experiments validate that the self-aligning features successfully absorb execution errors, enabling highly reliable robotic tool reconfiguration.