Motion Capture

This project uses the lighthouse technology or SteamVR tracking technology for developing low-cost position trackers. HTC uses the SteamVR tracking technology for their VIVE virtual reality system. Unlike video-based systems that use cameras, this system uses base stations or lighthouses which emit infra-red laser light. The laser light is intercepted by photodiodes which are mounted on the surface of an object called the tracker. The SteamVR tracking software can then estimate the bearing or the pose information of the trackers with respect to the base stations by recording the timestamp information of when the photodiodes get hit with the laser light. The timestamp information along with the relative photodiode distance information is then used to estimate the spatial position and orientation of the position trackers. Along with optical tracking this technology also uses IMUs for dead reckoning. The system is quite analogous to the GPS navigation systems where multiple satellites help triangulate the position of a GPS receiver based on highly accurate timestamp information.

The current works with the technology focus on developing compact and body mountable position trackers for recording human biomechanics. The tracking performance is dictated by the location of the photodiodes on the tracker. This work entails solving the design optimization problem where we intend to find optimal positions and orientations for the photodiodes to have the best tracking performance results.

Motion Tracker Development

This project uses the lighthouse technology or SteamVR tracking technology for developing low-cost position trackers. HTC uses the SteamVR tracking technology for their VIVE virtual reality system. Unlike video-based systems that use cameras, this system uses base stations or lighthouses which emit infra-red laser light. The laser light is intercepted by photodiodes which are mounted on the surface of an object called the tracker. The SteamVR tracking software can then estimate the bearing or the pose information of the trackers with respect to the base stations by recording the timestamp information of when the photodiodes get hit with the laser light. The timestamp information along with the relative photodiode distance information is then used to estimate the spatial position and orientation of the position trackers. Along with optical tracking this technology also uses IMUs for dead reckoning. The system is quite analogous to the GPS navigation systems where multiple satellites help triangulate the position of a GPS receiver based on highly accurate timestamp information.

The current works with the technology focus on developing compact and body mountable position trackers for recording human biomechanics. The tracking performance is dictated by the location of the photodiodes on the tracker. This work entails solving the design optimization problem where we intend to find optimal positions and orientations for the photodiodes to have the best tracking performance results.

Sitole, S. P., LaPre, A. K., & Sup, F. C. (2020). Application and evaluation of lighthouse technology for precision motion capture. IEEE Sensors Journal, 20(15), 8576-8585.
LaPrè, A. K., Nguyen, V. Q., Baspinar, U., White, M., & Sup, F. C. (2017). Capturing prosthetic socket fitment: Preliminary results using an ultrasound-based device. In 2017 International Conference on Rehabilitation Robotics (ICORR) (pp. 1221-1226). IEEE.
Nie, Q., & Sup, F. C. (2017). A soft four degree-of-freedom load cell based on the hall effect. IEEE Sensors Journal, 17(22), 7355-7363.