HiPi: Reproducible High-Fidelity Piezoresistive Sensors for Robotic Manipulation

2026-06-09

AI Summary

This work addresses the longstanding challenge in resistive tactile sensing—balancing reproducibility, manufacturability, and high-fidelity signal readout—by introducing an end-to-end reproducible, high-fidelity resistive tactile sensing system. The design reconstructs the full hardware stack from circuit board to sensing layer, incorporating a compact, solder-free PCB layout, off-the-shelf MCU modules, a low-crosstalk readout architecture, an optimized communication protocol, and a flexible printed circuit board (FPCB)-based conductive layer, all fully compatible with standard PCB fabrication processes. Evaluated on a dual-arm robotic platform with four sensor arrays (2048 taxels total), the system achieves a 220 Hz readout rate and demonstrates superior contact geometry reconstruction, yielding an Intersection-over-Union (IoU) of 0.797 and a Dice score of 0.886—significantly outperforming baseline approaches—while offering ease of deployment and seamless scalability to multi-sensor configurations.

Abstract

Piezoresistive tactile sensors are attractive for robotic manipulation because they are thin, lightweight, low-cost, and scalable to dense large-area sensing. However, existing systems still face a practical trade-off: recent reproducible designs emphasize accessibility and ease of reproduction, whereas high-fidelity readout architectures remain more difficult to fabricate, assemble, and deploy. We present HiPi, a reproducible high-fidelity piezoresistive sensing system for robotic manipulation. Building on a low-crosstalk readout principle, HiPi redesigns the complete hardware stack around reproducibility, deployability, and multi-sensor scalability. The system includes a compact readout PCB compatible with commercial PCB fabrication and assembly services, eliminating manual soldering; a smaller and lower-cost STM32-based MCU module; an optimized communication pipeline that achieves 220 Hz readout in a bimanual setup with four dense tactile arrays (2048 taxels in total); and FPCB-based conductive layers that simplify sensor fabrication and stacking. Experiments with structured 3D-printed contact patterns show that HiPi preserves contact geometry substantially better than a reproducible baseline, improving the average IoU from 0.428 to 0.797 and the average Dice score from 0.539 to 0.886. These results suggest that HiPi bridges an important gap between reproducible fabrication and high-fidelity readout, making dense piezoresistive tactile sensing more practical for bimanual manipulation and multi-fingered robotic systems.

Problem

• piezoresistive tactile sensors
• reproducibility
• high-fidelity readout
• robotic manipulation
• dense tactile sensing

Innovation

• piezoresistive tactile sensing
• reproducible fabrication
• high-fidelity readout
• low-crosstalk architecture
• scalable robotic manipulation