To cover for losses in satellite visibility, which can occur in urban canyons, tunnels and under bridges, most OEM navigation systems have a dead reckoning (DR) capability that utilises vehicle wheel speed data and turn rate information (Yaw). When it comes to testing these systems on the bench, if the dead reckoning signals are not present, the OEM navigation systems will not function correctly. To overcome this, we have developed a full navigation system testing solution comprising of a LabSat 3 GNSS simulator, Video VBOX data logger, turntable and yaw rate sensor. Wheel speed data is recorded by the LabSat 3 from vehicle CAN or wheel speed pulse.
The turntable system can use GPS, Galileo, GLONASS or BeiDou satellite constellation data to record live drive data combined with vehicle yaw rate and wheel speed information. The turntable system can work with any GNSS based dead reckoning (DR) system.
All of this data is replayed in perfect alignment so that the turntable will simulate the physical turning required to activate the DR in the navigation system under test. The wheel speed and satellite RF data will activate the navigation system and in combination with video provide a realistic replay of the driven route.