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arXiv · 2508.20959

Scaling Fabric-Based Piezoresistive Sensor Arrays for Whole-Body Tactile Sensing

Curtis C. Johnson·Daniel Webb·David Hill·Marc D. Killpack
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Abstract

Scaling tactile sensing for robust whole-body manipulation is a significant challenge, often limited by wiring complexity, data throughput, and system reliability. This paper presents a complete architecture designed to overcome these barriers. Our approach pairs open-source, fabric-based sensors with custom readout electronics that reduce signal crosstalk to less than 3.3% through hardware-based mitigation. Critically, we introduce a novel, daisy-chained SPI bus topology that avoids the practical limitations of common wireless protocols and the prohibitive wiring complexity of USB hub-based systems. This architecture streams synchronized data from over 8,000 taxels across 1 square meter of sensing area at update rates exceeding 50 FPS, confirming its suitability for real-time control. We validate the system's efficacy in a whole-body grasping task where, without feedback, the robot's open-loop trajectory results in an uncontrolled application of force that slowly crushes a deformable cardboard box. With real-time tactile feedback, the robot transforms this motion into a gentle, stable grasp, successfully manipulating the object without causing structural damage. This work provides a robust and well-characterized platform to enable future research in advanced whole-body control and physical human-robot interaction.

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Curtis C. Johnson, Daniel Webb, David Hill, Marc D. Killpack. 2025-08-28. Scaling Fabric-Based Piezoresistive Sensor Arrays for Whole-Body Tactile Sensing. https://arxiv.org/abs/2508.20959

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