Distributed 3-D Bearing-Only Orientation Localization

We propose a method to recover the orientation of a set of agents with respect to a global reference frame using local bearing measurements alone. Our method is distributed, does not require prior rotation information, and considers the full 3-D version of the problem. We identify sufficient localizability conditions on the directed graph of measurements, propose an algorithm based on distributed Riemannian gradient descent to recover a localization, and verify our theoretical results with simulations.