An accelerometer-based physical rehabilitation system

This paper presents a portable physical rehabilitation monitoring system based on a personal network of intelligent sensors. Rehabilitation is traditionally carried out in hospitals under supervision of qualified personnel. However, significantly better results could be achieved using out-of-hospital portable monitoring to allow patients computer-assisted rehabilitation in their homes. The new generation of personal digital assistants (PDA), such as Compaq iPAQ, offers large processing power, decent graphical user interface, and compact flash based secondary memory. Therefore, they are perfectly suited for portable monitoring units. Individual sensors are positioned on limbs to analyze movements using 2-axis MEMS accelerometers. The system monitors periods and forces of individual sensors, visualizing relevant physiological data in real-time on PDA, and archiving progress data on compact flash. A specialist supervises current advance and sets new optimum rehabilitation modes, thresholds for forces, step periods, etc. The system generates real-time warnings when predefined thresholds have been exceeded. We are developing a system for hip and knee replacement rehabilitation, as well as general physical rehabilitation. Other possible applications of our system include rehabilitation of stroke and heart attack patients.