Testen von Koppelnavigations-Systemen

Unterschiedliche Straßenlayouts, verschiedene Arten von Kreuzungen und auf welcher Straßenseite gefahren wird, sind nur einige der vielen Herausforderungen für Entwickler von Navigationssystemen. Hinzu kommen die Kosten für die Prüfung in verschiedenen Ländern oder auf verschiedenen Kontinenten.

SatNav testing

Wie können Sie folglich, Ihre Firmware oder Software zuverlässig und wiederholbar testen? Für viele führende Anbieter und Entwickler von Navigationssystemen liegt die Antwort in der Aufnahme, Wiedergabe oder der Simulation von GPS- und Multi-GNSS-Signalen.

Warum Aufnahme und Wiedergabe von GNSS-Daten?

By recording from real satellite signals under poor reception conditions, such as. For example in tunnels and underpasses, or by repeatedly leaving the specified route, the complexity can be detected by today's driving conditions much more realistic than with a GNSS simulator.

The added scenarios will be played over and over again in order to standardize your testing program and to be able to ensure consistency test various software and firmware versions.

Different variants of cartography databases can also be tested.

Prüfung der Dead-Reckoning (Koppelnavigation)-Funktion

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. When it comes to testing these systems on the bench, if the dead reckoning signals are not present, the navigation systems will not function correctly. To overcome this, we have developed a full navigation system testing solution comprising of a LabSat GNSS simulator, a Video VBOX data logger, a turntable, an inertial measurement and a wheel speed generation unit.

The turntable system uses global satellite constellation data to record live drive data combined with vehicle yaw rate and wheel speed information.

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.

Wie funktioniert das LabSat-Drehplattensystem?

The LabSat records live-sky GNSS data, and synchronised vehicle signals from CAN. The LabSat then replays this data,  containing GPS L1 signals and/or GLONASS L1 signals (along with any from Satellite Based Augmentation Signals (SBAS) WAAS/ EGNOS/ QZSS) back to the device under test - accurately reproducing the satellite and CAN signals from all of those which were present during the recording.

The turntable will rotate, simulating the yaw rate of the car in its original drive. This combination of physical rotation and GPS data will then activate the navigation unit’s gyro, and therefore its dead-reckoning system.

As it is based on a real recording the data will replicate the satellite signal loss experienced in city centres and tunnels and maintain the dead reckoning solution until the signals are regained, just like the live drive. This makes the replay repeatable time and again to save you significant testing costs.

Warum Video?

LabSat turntable software has the ability to replay a Video VBOX video recording in synchronisation with the live recorded satellite data file. This will allow you to visually compare the position with the test performance. This is particularly useful in assessing the navigation system in and out of tunnels and in areas of poor satellite reception. All the replay data is managed by the LabSat software which has the flexibility to repeat the replay continuously to allow for accurate comparison and analysis.

The Video VBOX system can also create a custom scene in which a range of user defined data can be displayed on the video replay. This includes logos, headers, receiver data and information from the IMU. The picture within picture feature can also record the real time navigation screen data in a test vehicle, as well as the forward facing camera picture.

LabSat 3 Turntable solution

Rund um den Globus testen

SatGen simulation software can easily create a route and output artificial satellite RF data files. By uploading NMEA or KML files or by using the Google Maps interface a complex route can be defined and recorded. When this simulated signal data is replayed the system generates the yaw rate and wheel speed data required to operate the turntable and the navigation unit being tested.

By removing the Satellite data feed GNSS signal loss can easily be replicated in the navigation system whilst the DR function remains active.

SatGen software with an imported KML file
SatGen software with an imported KML file

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