Description:
Background
Wearable motion tracking technology has the potential to revolutionize injury rehabilitation, sports science, and virtual reality, but widespread adoption has yet to be realized due to limitations of the conventional camera- or accelerometer-based technologies. Current systems are bulky, power-hungry, and require line-of-sight or suffer from significant drift.
USC Solution
USC researchers have developed a 3D real-time motion tracking system using frequency-division-multiplexed magnetic induction. The network of wearable, wireless sensor nodes extracts spatial information via measured node-to-node coupling. Each node is a transceiver, concurrently transmitting a single tone and sensing low-frequency (MHz range) magnetic fields transmitted by all other nodes. The custom transceiver chip is fabricated in 180nm CMOS and is low power (<5-10 mA/sensor) relative to inertial sensors (40 mA/sensor). The CMOS technology is low cost, high-volume compatible, and amenable to miniaturization. The system offers high tracking reliability without the need for a calibration adjustment (like inertial sensors) or line-of-sight (like cameras).
Applications
- Healthcare: rehabilitation and physical therapy monitoring
- Sports Science: biomechanics and performance analytics
- Virtual Reality: high frame rate user motion tracking
Stage of Development
Proof of concept on 3D-printed model and human joints
Key Publications
Rustom, M., Farhadian, A., Nguyen, T.D., Moghaddam, M. and Sideris, C., 2025, June. Frequency-Division Multiplexed Magnetic Induction Based Wireless Wearable Sensor Network for Real-Time Motion Tracking. In 2025 Symposium on VLSI Technology and Circuits (VLSI Technology and Circuits) (pp. 1-3). IEEE. https://doi.org/10.23919/VLSITechnologyandCir65189.2025.11074912