NIKE BLUETRACK: Blue Force Tracking in Underground Structures

A blue force tracking system sends position information of the own forces to the command post. Typically, such systems use Global Navigation Satellite Systems (GNSS). Since GNSS is not available in underground structures, a new concept must be found. In this article we present a localization system for operators in underground structures, such as tunnels or subways. By fusing inertial data (accelerations and angular rates) sensed by an Inertial Measurement Unit (IMU) with distance measurements from Ultra-Wideband (UWB) and map information from a 3D model, a robust blue force tracking system is introduced. The challenges here are that the needed infrastructure and an existing 3D model cannot be assumed to be available. Thus, algorithms and tools are developed to provide the necessary information in near real-time. Our tests in a street tunnel at Zentrum am Berg (ZaB) showed that the developed system provides robust localization information on the own forces.