FRANKFURT, Germany—Continental A.G. engineers are developing an aquaplaning alert system that uses signals from surround-view cameras and tire-mounted electronic sensors to warn the vehicle's driver and engage active stabilization measures.
"Wet road conditions are difficult for a car driver to evaluate," Bernd Hartmann, head of enhanced Advanced Driver Assistance Systems and tire interactions at Continental's Chassis & Safety Division.
"Once you feel your vehicle floating, it is too late. Our aquaplaning-assistance concepts detect the early aquaplaning phase to make the driver aware of what is going on under the tires. This can help drivers or automated vehicles to adapt their speed appropriately to wet road conditions."
The system under development, dubbed "Road Condition Observer," is all encompassing, using input from the tires, tire-sensors, cameras, algorithms, brake actuation and the human-machine interface, Hartmann said.
According to Conti, aquaplaning occurs when standing water on a road surface is deep enough to cause the tire to lose contact with the road surface and begin to float. Braking and steering are no longer possible, and the driver loses control of the vehicle.
As such, Conti's technicians are focused on predicting and managing the risk of aquaplaning by detecting conditions conducive to it as early as possible so as to trigger an early warning to the driver. Conti aims to do this by using signals from surround view cameras and tire-mounted eTIS (electronic-Tire Information System) sensors.
The Hanover, Germany-based tire and vehicle systems supplier also is working on the control and stabilization of vehicles in aquaplaning situations, such as torque vectoring by individual wheel braking.
Aquaplaning conditions can occur unexpectedly with no opportunity for advance warning, Conti said. In such cases, the potential risk to other vehicles on the road can be mitigated by early car-to-car communication via V2X technology and eHorizon, facilitating a network of solidarity where one vehicle acts as a safety sensor for all other vehicles and not just those in its direct vicinity.
Conti noted that surround-view cameras mounted on a vehicle's outside rear-view mirror, grill and rear can recognize a specific splash and spray pattern of the tires that can be recognized as aquaplaning in its early phase.
Conti is studying these patterns in order to develop "wetness recognition" algorithms that will be integral to the system in predicting potential aquaplaning conditions.
In addition, the eTIS sensors mounted on the tire's inner liner can deliver critical data, such as the radial acceleration of the part of the tire that is in contact with the road. As soon as the water on the road becomes deep enough to effect grip, the acceleration signal begins to oscillate in a characteristic way, indicating an early risk of aquaplaning, Conti said.
Since the eTIS sensors can also detect a tire's remaining tread depth, a safe speed for a given wet road condition can be calculated and communicated to the driver.
Testing has shown that future aquaplaning assistance will also have the potential to intervene in an actual aquaplaning situation by applying the rear brakes in a controlled way to establish a degree of "torque vectoring" in order to maintain vehicle maneuverability within physical limits.