Spring constant measurement using a MEMS force and displacement sensor utilizing paralleled piezoresistive cantilevers

Abstract

This paper reports on a method to measure a spring constant on site using a micro electro mechanical systems (MEMS) force and displacement sensor. The proposed sensor consists of a force-sensing cantilever and a displacement-sensing cantilever. Each cantilever is composed of two beams with a piezoresistor on the sidewall for measuring the in-plane lateral directional force and displacement. The force resolution and displacement resolution of the fabricated sensor were less than 0.8 µN and 0.1 µm, respectively. We measured the spring constants of two types of hydrogel microparticles to demonstrate the effectiveness of the proposed sensor, with values of approximately 4.3 N m−1 and 15.1 N m−1 obtained. The results indicated that the proposed sensor is effective for on-site spring constant measurement.

Design of a Tribotester Based on Non-Contact Displacement Measurements

“…From the results of the calibration to analyze the relationship between the applied force and the displacement of the cantilever tip, it is confirmed that the cantilever tip stiffness (3,950 N/m) in the lateral direction is approximately five times larger than the cantilever tip stiffness (710 N/m) in the vertical direction. The stiffness of the cantilever tip can be calculated using Equation (1) [29,30]:S=f N/d m where S is the stiffness of the cantilever tip, and d and f are the displacement and force generated in the vertical and lateral directions, respectively.…”

A measuring method for micro force based on MEMS planar torsional spring

“…MEMS spring is a typical microstructure, which not only provides elastic force but also transmits energy [4][5]. It is a key component of many micro-sensors [6] and actuators [7][8], and its performance determines the accuracy, output linearity of the device. Some researchers have tried to apply and measure the micro force with MEMS springs as driving sources.…”