Indoor Cooperative Localization for a Swarm of Micro UAVs Based on Visible Light Communication

This article proposes an indoor cooperative positioning system for a swarm of micro unmanned aerial vehicles (UAVs) based on visible light communication. The proposed cooperative positioning system is composed of light-emitting diodes (LEDs) installed on the ceiling and a group of micro UAVs. Each micro UAV is composed of a single LED and multiple photodiodes (PDs) with a uniform distribution. The cooperative positioning of a group of micro UAVs is achieved through the LEDs installed on the ceiling and the interactive positioning information shared among them. In order to solve the nonconvex optimization function constructed by cooperative localization, an improved bat algorithm based on adaptive parameters was designed. In the proposed cooperative localization scenario, the theoretical lower bound of the localization error, i.e., the Cramer–Rao lower bound, is precisely analyzed by mathematical method. Simulation and experimental results demonstrate that compared with the single PD receiving technology, the multi-PD receiving technology can significantly improve the positioning accuracy, while the cooperative positioning technology can significantly improve the positioning accuracy compared with the noncooperative positioning technology.