A wireless personal wearable network system to understand the biomechanics of orthotic for the treatment of scoliosis

The wear tightness of an orthosis for the treatment of scoliosis varies greatly during daily activities. Currently, there is no commercially available product that can monitor force distribution inside the brace and the time that the othosis is worn during daily activities. Subjective feeling is the most commonly used method. To provide an objective measure, a battery-powered wireless personal wearable network system is developed. This system consists of up to 16 wireless force loggers and a USB ZigBee dongle. Each logger contains a force sensor and a wireless unit. The whole system records how much time the orthosis has been used and how loads distribute inside the orthoses. Laboratory tests have been performed; the maximum force measurement error is ±0.02N and the resolution is 0.1N. The average power consumption of the system is 0.3mW/h and thus a single AAA-sized alkaline battery is able to support the power for 6 months.