Abstract
With the development of Internet of Things and wearable devices, human motion analysis in daily-living environment has attracted more attention. Accelerometers have been widely used in the quantitative analysis of human motion. However, the outputs of accelerometers include both the acceleration from gravity and the human motion accelerations as well as acceleration from noises. Consequently the accelerations of body segments of interest cannot be measured directly. In this paper, a wireless wearable sensor with a triaxial accelerometer, a triaxial gyroscope and a triaxial magnetic sensor was designed, and a new method by integrating a three-order low-pass filter and a Kalman filter was proposed to estimate the sensor orientation. This system is able to extract the acceleration only due to the body motion with a higher accuracy. It also can transmit sensor data to a personal computer using a ZigBee wireless module. The new fusion algorithm makes the motion sensor system suitable to various cases for analyzing the human daily activities.
