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IFEN ’ s integrated ( GNSS , foot-mounted IMU and QR codes ) navigation device applied for supporting fire fighters

In the course of this paper, a by IFEN GmbH developed integrated navigation device for aiding and rescuing fire fighters in emergency situations is presented. In areas with sufficient signal strength the respective rescue force is tracked by means of GNSS/INS position information, whereas indoor or in areas without GNSS support, the positioning is conducted by means of a foot mounted inertial measurement unit and the according strap-down architecture. As an improving measure, the conducted strap-down algorithm was also supported by the introduction of so called ZUPT ́s (Zero Velocity Updates) to stabilize the inertial navigation system. For recalibration issues, QR codes providing the system with WGS84 position information were placed at specific strategic points within buildings. Finally the separate navigation results were integrated by means of a Helmert Transformation, to obtain the fire fighters position in WGS84