Tac2Structure: Object Surface Reconstruction Only through Multi Times Touch

TL;DR

This paper introduces Tac2Structure, a tactile-based surface reconstruction framework that uses only a vision-based tactile sensor and advanced algorithms to achieve millimeter-level accuracy without external devices.

Contribution

The novel framework enables accurate object surface reconstruction solely through multi-touch measurements, reducing errors and eliminating the need for external sensors or strong prior assumptions.

Findings

Achieves millimeter-level surface reconstruction accuracy.

Reduces cumulative errors during global surface reconstruction.

Uses deep learning for loop-closure detection in tactile data.

Abstract

Inspired by humans' ability to perceive the surface texture of unfamiliar objects without relying on vision, the sense of touch can play a crucial role in robots exploring the environment, particularly in scenes where vision is difficult to apply, or occlusion is inevitable. Existing tactile surface reconstruction methods rely on external sensors or have strong prior assumptions, making the operation complex and limiting their application scenarios. This paper presents a framework for low-drift surface reconstruction through multiple tactile measurements, Tac2Structure. Compared with existing algorithms, the proposed method uses only a new vision-based tactile sensor without relying on external devices. Aiming at the difficulty that reconstruction accuracy is easily affected by the pressure at contact, we propose a correction algorithm to adapt it. The proposed method also reduces the accumulative errors that occur easily during global object surface reconstruction. Multi-frame tactile measurements can accurately reconstruct object surfaces by jointly using the point cloud registration algorithm, loop-closure detection algorithm based on deep learning, and pose graph optimization algorithm. Experiments verify that Tac2Structure can achieve millimeter-level accuracy in reconstructing the surface of objects, providing accurate tactile information for the robot to perceive the surrounding environment.