Intelligent Wearable Interfaces

CHAPTER 8

Intelligent Mobile Human Airbag System

8.1 INTRODUCTION

A human airbag system is designed to reduce the impact force from slippage falling-down. A micro inertial measurement unit (μIMU), which is based on Micro ElectroMechanical System (MEMS) accelerometers and gyro sensors is developed as the motion sensing part of the system. A recognition algorithm is used for real-time falling determination. With the algorithm, the microcontroller integrated with μIMU can discriminate falling-down motion from normal human motions and trigger an airbag system when a fall occurs. The airbag system is designed to be a fast response with moderate input pressure; i.e., the experimental response time is less than 0.3 sec. under 0.4 MPa. Also, we present our progress on using this μIMU based on support vector machine (SVM) training to recognize falling-motions. Experimental results show that selected eigenvector sets generated from 200 experimental data can be separated into falling-motion and other motions completely.

It is well known that the world is facing an increasingly aging population. With this increase, the proportion of frail and dependent elderly is also likely to increase significantly [1]. This shift in demographic pattern will lead to an exponential increase in the number of elder individuals suffering from injury of falls; i.e., falls and fall-induced fractures are very common among the elderly.

Hip fractures account for most of the deaths and costs of all fall-induced fractures. ...