Gait analysis for freezing detection in patients with movement disorder Using three dimensional acceleration system

Due to the aging process, the aftereffect of an accident or the problems in brain, some people can experience difficulties in walking. It could be helpful in the treatment of these individuals suffering walking difficulties to monitor their movement. The Unconstrained Activity Monitoring System (U-AMS) was developed to monitor the body's acceleration. It can be attached easily and doesn't interfere with daily activity. The hardware consists of 3-axis accelerometer, which records data for long periods of time. The movement image was simultaneously recorded by a camcorder. To collect data from U-AMS and analyze them, several programs were developed. The data were transferred to a computer by RS-232 module and displayed through viewing program made by MFC (Microsoft, USA). The analyzing program, which links viewing program to MATLAB (Mathworks, USA), analyzes the data to detect movement disorder. In this paper, freezing, which is characterized as start hesitation., was the target disorder. Using the different characteristics in frequency domain between freezing and normal gait, freezing appearances were detected. By comparing with movement image, the accuracy of the freezing detection was verified to have a good performance.