Fig. 1

Wearable system hardware. Eight distributed nodes (Dots) simultaneously send and receive data to and from the central control unit (Hub) where real-time computation and control algorithms are performed. Dots are configured in custom software to act as sensing Dot, feedback Dot, or both. Each Dot is comprised of a 9-axis inertial measurement magnetometer unit (IMMU) sensor, vibrotactile feedback motor, ZigBee wireless communication module, and a 100 mAh lithium ion battery. All Dot components are embedded in a single silicon mold. Each Dot weighs about 12 g and the overall top surface area is roughly the same as a 25 mm coin