Textile‐Based Wireless Pressure Sensor Array for Human‐Interactive Sensing

TLDR

The authors propose a textile‑based wireless pressure sensor array (WiPSA) for flexible remote tactile sensing applications. WiPSA consists of a fabric spacer between two passive antenna layers and a ferrite film, and pressure compresses the spacer, altering inductance and shifting resonant frequency, while the high‑permeability ferrite enhances sensitivity and suppresses conductive interference. WiPSA achieves a quality factor >35, sensitivity of –0.19 MHz kPa⁻¹ over 0–20 kPa, and maintains performance after >20 000 cycles, 15–103 °C, and 40–99 % humidity, and is demonstrated in wrist‑band, insole, and belt prototypes for human‑interactive sensing.

Abstract

Abstract A textile‐based wireless pressure sensor array (WiPSA) is proposed for flexible remote tactile sensing applications. The WiPSA device is composed of a fabric spacer sandwiched by two separate layers of passive antennas and ferrite film units. Under the external pressure, the mechanical compression of the flexible fabric spacer leads to an inductance change, which can further be transduced to a detectable shift of the resonant frequency. Importantly, WiPSA integrates the ferrite film featuring an ultrahigh permeability, which effectively improves the device sensitivity and avoids the interference of conductive materials simultaneously. The device performance with a high quality factor (>35) and sensitivity (−0.19 MHz kPa −1 ) within a pressure range of 0–20 kPa is demonstrated. In addition, WiPSA achieves excellent reproducibility under periodical pressures (>20 000 cycles), temperature fluctuations (15–103 °C), and humidity variations (40–99%). As a proof of concept for human‐interactive sensing, WiPSA is successfully 1) integrated with a flexible wrist band for fingertip pressure‐guided direction choices, 2) developed into a smart wireless insole to map the plantar stress distributions, and 3) embedded into a waist‐supporting belt to resolve the contact pressure between the belt and human abdomen in a remote transmitting scheme.