In the new Porsche 911, a “Structural Health and Knock Emission” (SHAKE) sensor from Hella is integrated in the front wheel arch liners for moisture detection. The piezoelectric SHAKE sensor detects the road condition and detects the water film on the road surface.
In the field of driver assistance systems, Hella has therefore further developed the so-called SHAKE technology. This complements existing assistance and safety systems, as it enables the vehicle not only to "see" its surroundings (for example via radar and camera systems), but also to "feel" them, thus covering the invisible area between all driver assistance systems in the immediate vicinity of the vehicle. Using a piezoelectric element, the SHAKE sensor detects, for example, vibrations and airborne noise from swirling water droplets and determines the degree of wetness between the tire and the road.
If the system detects a wet road, the response behaviour of Porsche Stability Management (PSM) and Porsche Traction Management (PTM) is preconditioned. In addition, the driver receives a warning and a recommendation to switch to wet mode. Various systems, such as the response behaviour of the drive, then adapt to ensure the greatest possible driving stability. "This is a great advantage over most systems available to date, which only warn when a critical driving situation with a very wet road has already occurred," says Michael Jaeger, who is responsible for the actuators and sensors in the management of Hella's electronics division.
In addition, the moisture sensor also has potential for autonomous driving. "Precise information about road conditions is crucial in order to determine static friction and thus also braking distance. This is precisely what the SHAKE sensor can reliably determine.
In addition to the SHAKE sensor, Hella also supplies the interior light, central control units and sensors for accelerator pedal sensors.