Ultra-Broad-Range Pressure Sensing Enabled by Synchronous-Compression Mechanism Based on Microvilli-Microstructures Sensor

Abstract

A sensor which is able to detect both the high- pressure and the subtle pressure is crucial for applications such as physiological health monitoring and human-machine interactions. However, current sensors often struggle to meet these requirements, as they usually rely on a single compression mechanism. In this study, a microvilli-microstructures sensor is reported which is capable of tracking ultra-broad-range pressures based on a synchronous-compression mechanism. The synchronous-compression mechanism includes: i) the increase of microvilli-induced electron-transfer, ii) the increase of microstructure contact area, and iii) the decrease of multi-walled carbon nanotubes spacing. At the high-pressure stages, the mechanisms contribute synchronously to changes in resistance. Hence, this sensor can measure a 5 kPa pressure change under the extremely high- pressure (750 kPa) conditions of meniscus simulation, where the commercial sensor fails. This sensor exhibits a high sensitivity of 58.88 kPa⁻¹, an ultra-broad working range from 50 Pa up to 782.5 kPa, a rapid response time of 9 ms, and a long-duration (under 250 kPa pressure, cycling for 10,000 times). This flexible pressure sensor also shows versatility and potential for various applications. The synchronous-compression mechanism proposed here can inspire future designs of high-performance flexible sensors.