SaFePlay is a portable, self-operating and smart feedback wearable health promotion system. It monitors knee joint condition and provides gait adjustment suggestions instantly to the user during all kind of activities. The aim is to reduce the pressure exerted on the knee joints, in order to prevent knee osteoarthritis (OA) or mitigate the pain for knee OA patients. In the past, gait examination and correction suggestions can only be done in the specific clinical centre, using expensive facilities that can only be operated by professional or well-trained technicians. The SaFePlay system provides a more efficient self-operational solution that allows users to self-monitor their gait without any professional knowledge.
The SaFePlay system consists of wearable devices, including a pair of insoles, a pair of knee sleeves, a mobile application, and OLED lights that provide visualised feedback. OLED lights are placed surround the knee sleeves to alert the unsafe load on the knee joint. The insole includes a motion sensor, four vibration motors, and 18 pressure and shear force sensors that cover the whole sole area. The four vibration motors perform various patterns of vibrations and advice the user to correct the foot postures. By applying the SaFePlay analysis technique, users can get measurements on the progression angle, stride length, stride width, pressure and shear distribution on the foot, as well as the transformation trajectory of the pressure centre of the foot during activities. Feedback is provided via various vibration patterns.
The SaFePlay app switches between several activities modes, including hiking, jogging, running, cycling and daily normal walking. It provides real-time suggestions to adjust the gait/posture based on different activities. All the modes show real-time information, which are collected from the knee sleeves. The data is then recorded on the user’s mobile phone or uploaded to the SaFePlay cloud server. This allows user to play back and examine their gait/posture.
Institute for Information Industry, Taiwan, R.O.C
Chiu Ting-Wei, Lo Yi-Ping, Ma Chih-Chun, Wang Hsing-Man