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arXiv · 2503.06848

Eye-in-Finger: Smart Fingers for Delicate Assembly and Disassembly of LEGO

Zhenran Tang·Ruixuan Liu·Changliu Liu
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Abstract

Manipulation and insertion of small and tight-toleranced objects in robotic assembly remain a critical challenge for vision-based robotics systems due to the required precision and cluttered environment. Conventional global or wrist-mounted cameras often suffer from occlusions when either assembling or disassembling from an existing structure. To address the challenge, this paper introduces "Eye-in-Finger", a novel tool design approach that enhances robotic manipulation by embedding low-cost, high-resolution perception directly at the tool tip. We validate our approach using LEGO assembly and disassembly tasks, which require the robot to manipulate in a cluttered environment and achieve sub-millimeter accuracy and robust error correction due to the tight tolerances. Experimental results demonstrate that our proposed system enables real-time, fine corrections to alignment error, increasing the tolerance of calibration error from 0.4mm to up to 2.0mm for the LEGO manipulation robot.

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Zhenran Tang, Ruixuan Liu, Changliu Liu. 2025-03-10. Eye-in-Finger: Smart Fingers for Delicate Assembly and Disassembly of LEGO. https://arxiv.org/abs/2503.06848

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