A Sensor Position Localization Method for Flexible, Non-Uniform Capacitive Tactile Sensor Arrays

TL;DR

This paper introduces VARSkin, a capacitive tactile sensor array with variable density, and a localization method that accurately determines sensor positions within a non-uniform array, enhancing robotic tactile sensing capabilities.

Contribution

The paper presents a novel localization method for variable-density tactile sensor arrays, enabling precise sensor position estimation in non-uniform configurations.

Findings

Achieves sensor position localization within ±2mm accuracy.

Demonstrates effectiveness on two different artificial skin patches.

Provides error analysis and strategies for improving localization precision.

Abstract

Tactile sensing is used in robotics to obtain real-time feedback during physical interactions. Fine object manipulation is a robotic application that benefits from a high density of sensors to accurately estimate object pose, whereas a low sensing resolution is sufficient for collision detection. Introducing variable sensing resolution into a single tactile sensing array can increase the range of tactile use cases, but also invokes challenges in localizing internal sensor positions. In this work, we present a mutual capacitance sensor array with variable sensor density, VARSkin, along with a localization method that determines the position of each sensor in the non-uniform array. When tested on two distinct artificial skin patches with concealed sensor layouts, our method achieves a localization accuracy within $\pm 2mm$. We also provide a comprehensive error analysis, offering strategies for further precision improvement.