A low cost flame-retardant 4 material accelerometer for low-frequency vibration detection

Abstract Low-frequency vibrations of large buildings and bridges caused by factors such as earthquakes can lead to structural damage, therefore monitoring their vibration characteristics is of great importance for the safety of society. The fabrication of conventional silicon-based microelectromechanical system accelerometers involves microfabrication processes, resulting in escalated production costs. In this paper, we present an innovative area-varying capacitive accelerometer that can be achieved by low-cost and rapid fabrication. The accelerometer uses flame resistant 4 glass epoxy laminate material as the substrate of the accelerometer. And it is optimized through theoretical analysis and ANSYS finite element method simulation. It utilizes a cost-effective PCB production process to fabricate the metal electrodes, which are used to form the capacitive array for sensing, and CNC machining for the spring–mass structure. Experimental results demonstrate that the accelerometer achieves a high sensitivity of 1290 mV g −1 , a quality factor of 224, a fundamental frequency of 8.3 Hz, and also exhibits a low repeatability error of 2.27%, and a low nonlinearity of 2.52%. In addition, the accelerometer demonstrate good temperature stability and resistance to metal interference. The proposed design and processing methodology offer a cost-effective solution for the realization of low-frequency vibration monitoring.