Modeling of a Novel AlN Nanogenerator-Based Self-Powered MEMS Arterial-Pulse Sensor

A self-powered continuous arterial-pulse monitoring system can improve the treatment quality, and hence, lengthen patient’s life. Conventional pulse monitoring sensors have significant power consumption drawbacks that limit their continuous operation. To overcome this limitation, a lead-free, biocompatible, and high-performance aluminum-nitride (AlN) piezoelectric nanogenerator-based self-powered (energy-harvesting) MEMS sensor is proposed which is capable of continuously monitoring arterial-pulse. This article presents a comprehensive physics-based mathematical modelling and numerical simulation results that deliver optimized design parameters for a novel piezoelectric thin-film MEMS diaphragm energy-converter (transducer) for improved sensitivity and fatigue stress life-span. The sensor yields a nano-generation sensitivity of 0.13V/kPa, which is much better than recently reported nanogenerator-based arterial-pulse sensors. Most materials encounter premature failure due to fatigue when subjected to cyclic loading. Damage-accumulation and cycles to fatigue-failure were also estimated using FEM simulations. The sensor’s viability is around
$10^{8.03}$
cycles before structural-failure for pressure amplitude-range from 10.6kPa to 16kPa (Range of arterial blood pressure).