Lighthouse Localization of Miniature Wireless Robots

In this paper, we apply lighthouse localization, originally designed for virtual reality motion tracking, to positioning and localization of indoor robots. We first present a lighthouse decoding and tracking algorithm on a low-power wireless microcontroller with hardware implemented in a cm-scale form factor. One-time scene solving is performed on a computer using a variety of standard computer vision techniques. Three different robotic localization scenarios are analyzed in this work. The first is a planar scene with a single lighthouse with a four-point pre-calibration. The second is a planar scene with two lighthouses that self calibrates with either multiple robots in the experiment or a single robot in motion. The third extends to a 3D scene with two lighthouses and a self-calibration algorithm. The absolute accuracy, measured against a camera-based tracking system, was found to be 7.25 mm RMS for the 2D case and 11.2 mm RMS for the 3D case, respectively. This demonstrates the viability of lighthouse tracking both for small-scale robotics and as an inexpensive and compact alternative to camera-based setups.