A collaboration between AVL and Rohde & Schwarz, two providers of measuring and automotive testing systems, now permits the reproduction of realistic GNSS reception conditions for vehicle testing on a testbed. As a result, the companies claim, users can reliably test all aspects of GNSS-based vehicle positioning – a core functionality of autonomous vehicles. GNSS signals – for example GPS signals – are of major importance for positioning and tracking, orientation and safety-related information, such as congestion, in road traffic.
AVL’s DrivingCube testbed provides reproducible testing of driver assistance systems and driving features for self-driving vehicles using a real vehicle within a virtual environment in a variety of different traffic situations. For that purpose, test drives are performed with a real, ready-to-drive vehicle on a chassis dynamometer or powertrain testbed. With the help of realistic virtual driving scenarios, it is possible to test peripheral sensors, control systems and actuators inside the vehicle in a reproducible and reliable manner. Automated vehicle functions are thus sufficiently validated during development and even before testing on the proving ground.
Effective immediately, the range of environment simulations carried out with AVL DrivingCube can now be extended to include GNSS signals, bringing simulation closer to reality than ever before. The vehicle’s GNSS receiver (e.g. GPS) is stimulated realistically using GNSS signals generated on the testbed. This way, technical engineers can identify exactly how sensors, automated driving features and other actuators respond inside the vehicle. The GNSS-based vehicle positioning feature that’s now possible is a core functionality of automated driving and the approach ensures that it is reliably tested.
To generate GNSS signals, Rohde & Schwarz GNSS stimulators are used (R&S SMBV100B or R&S SMW200A), which generate signals for all of the available satellite navigation systems (GPS, Glonass, Galileo, BeiDou, QZSS, SBAS) across all frequency bandwidths (L1, L2, L5). This also makes them suitable for testing multi-frequency receivers, which are playing an increasingly important role in automated driving, AVL says.
“By generating consistent GNSS signals in connection with environment simulation, AVL DrivingCube now provides a test system that enables users to validate GNSS-based driver assistance systems and autonomous driving features,” said Dr.-Ing. Tobias Düser, head of the advanced solution lab at AVL Deutschland.
Christoph Pointner, head of signal generators at Rohde & Schwarz, added, “We are very pleased to bring our expertise in the field of signal generation to this collaboration with AVL and to contribute to such an important innovation and trendsetting solution for testing automated driving features.”
AVL believes that additional GNSS stimulation not only makes testbed testing more realistic but is a further step in moving testing from the road to the rig. This leads to a much sharper reduction in the test drives required than was the case previously and major savings in the kilometers driven.
Rohde & Schwarz GNSS stimulators form a flexible, modular system that can be adapted to customer requirements and are easily integrated into the AVL DrivingCube environment. The stimulator is controlled automatically from the simulation platform.