Cooperative Localization of Unmanned Aerial Vehicles Using GNSS, MEMS Inertial, and UWB Sensors

Abstract

Cooperative networks of low-cost unmanned aerial vehicles (UAVs) are attracting researchers because of their potential to enhance UAV performance. Cooperative networks can be used in many applications, including assisted guidance and navigation, surveillance, search and rescue, disaster management, defense, mapping, precision agriculture, and mineral exploration. Such cooperative networks of UAVs can act as ad hoc networks and share information among different network nodes. Such information sharing makes these nodes more robust and efficient for the intended purpose. The location of UAVs is traditionally determined using a global navigation satellite system (GNSS), which limits the use of UAVs in regions that lack GNSS. However, the location of UAVs can be determined even in environments without GNSS through a cooperative network if a few of the nodes have access to GNSS. This is achieved by sharing the information among the nodes of the network. Information sharing in a cooperative network further results in improvement in the proportional accuracy of the nodes in cases where GNSS is available to all nodes. This study investigated a mathematical model and operational framework for cooperative localization of UAVs using GNSS, microelectromechanical systems (MEMS), inertial navigation system (INS), and UWB (ultra-wide-band) sensors under different architectures. This paper briefly discusses the practical feasibility of different distributed architectures and provides a comparison of distributed and centralized architectures. The study analyzed the proposed network using numerical simulation and investigated changes in performance with respect to different parameters. The simulation results show that the centralized architecture generally provided higher localization accuracy compared with the distributed architecture. It was also observed that reliable and consistent localization can be achieved, irrespective of the size of the network, by using a cooperative approach even if only four nodes have GNSS access in the network if there is good connectivity among the nodes. Further, the simulation results demonstrate that a cooperative approach benefits all the nodes in terms of improved localization accuracy even if all the nodes have access to GNSS.