Fabrication of a cost-effective MEMS-based piezoresistive cantilever sensor for gait movement analysis

Abstract

Gait analysis measurement is a method to access and identify gait events and the measurements of motion parameters involving the lower part of body. This significant method is widely used in rehabilitation, sports as well as health diagnostic towards improving the quality of life. However, it is not routine practice due to costs involved in creating and using gait labs. Alternatively, inertial sensors such as micro cantilever accelerometer can be used in the development of cheap and wearable gait analysis systems. Human stride segmentation measurement based on micro-accelerometer cantilever is used in the study of the lower limb movement patterns that include walk, jump and run; and the measurements of the motion parameters. A complete system consists of a fabricated sensor, a Wheatstone bridge circuit and a signal amplifier tailored for real-time stride analysis measurement is proposed. The novel fabrication method of an accelerometer sensor using laser micromachining is introduced in order to develop a simple way in realizing the sensor formation. This study allows us to optimize the requirements of hard-mask and fabrication process steps by reduction of 30% and 25% respectively. In the general framework, this research activity is focused towards development of piezoresistive cantilever formation using laser micromachining for fast fabrication development for real life gait and stride segmentation measurement application.