LOSA-X is a novel, low-cost, expandable 3D motion tracking system with the ability to adapt to dynamic background illumination. The tracking system consists of multiple tracker modules equipped with a Linear Optical Sensor Arrays (LOSA) and a 9-DOF Inertial Measurement Unit (IMU) for position and orientation tracking of a wireless IR-LED illuminated active marker as shown in fig. 1a. The active marker is a small polyhedron, cube in this iteration, with an independently controlled high power, near IR LED, on each surface and an MEMS IMU sensor fitted inside it. The cube structure enables the marker to emit light in any direction using its six LEDs as shown in fig.1b. Fig. 1c shows schematics of the tracker module. Each tracker module is a battery-powered module (although USB power is possible). The IR (remote) receiver sensor (TSMP6000) is placed on the center of the tracker module to determine the visibility and lighting of the active LED marker.
With the technology of extracting background illumination, as shown in fig.1d, the system could work robustly in different sense illuminations (static or dynamic) as shown in fig. 2a. By applying extended Kalman filter based sensor fusion architecture for combining data acquired from multiple trackers and marker, the tracking accuracy and operational range are enhanced as shown in fig. 2b.
  Kumar, A., Ben-Tzvi, P., "Spatial Object Tracking System Based on Linear Optical Sensor Arrays," IEEE Sensors Journal, Vol. 16, Issue 22, pp. 7933-7940, November 2016.
  Ren, H., Kumar, A., Ben-Tzvi, P., "LOSA-X: Expandable 3D Motion Tracking System", IEEE Sensors Journal, Under Review, July 2018.