Modern vehicles with driver assistance systems usually detect when something is wrong with the sensors and warn the driver of a system failure. But what if the sensors are so minimally adjusted that the vehicle does not yet report a fault? DEKRA experts investigated this question in driving tests at the DEKRA Technology Center at the Lausitzring in Brandenburg, Germany. The consequences of so-called sensor misalignments were examined. “We found that even the smallest impairments below the so-called self-diagnosis threshold can lead to a malfunction that endangers safety”, Christoph Bahnert, Team Leader for Driver Assistance Systems and Highly Automated Driving at DEKRA Automobil GmbH in Klettwitz, points out. The results of the driving tests are also taken up in the DEKRA Road Safety Report 2023 “Technology and People”.
- Self-diagnosis is not sufficient to ensure functional behavior
- Sensors should definitely be checked during vehicle inspection
- Issue gains further importance with increasing automation
Case A was carried out with three different test vehicles, each of which had an emergency brake assistant and was also equipped with high-precision measurement technology. The DEKRA experts ran two standard Euro NCAP scenarios: approaching a stationary vehicle or target and detecting a dummy pedestrian on the roadway. The speeds driven were 20, 40 and 60 km/h respectively (12, 25 and 37 mph). When the camera was correctly aligned, all three vehicles warned the driver in good time and braked to a standstill in front of the respective target.
The need to test sensor technology as part of periodic vehicle monitoring naturally applies not only to the front camera but also to other sensors such as rear radar, as test case B illustrates.