Polestar Performance has filed a patent with the European Patent Office that describes an innovative system aimed at detecting grip loss at a driven wheel and taking corrective action to restore traction. The system identifies when a predetermined amount of grip has been lost and responds by applying an oscillating steering motion to the affected wheels. This targeted steering action reduces wheelspin, improves traction, and enhances overall vehicle stability, offering a more refined approach to maintaining control in challenging driving conditions.
The Next Level Of Traction Control
Traction control is an integral part of cars’ stability-control systems nowadays, and aims to reduce wheelspin and optimize tire grip on acceleration. The system is typically electronically controlled and uses various inputs, such as those of the ABS sensors, to read wheel speeds and to determine which wheels are losing traction. Traction can then be restored by reducing engine power, activating individual brakes, or both.
Wiggling the steering from side to side can sometimes be all a spinning wheel needs to regain some traction, and Polestar describes a system that seems to do exactly this to improve the current state of the traction-control art. By applying oscillating steering input to affected wheels, wheelspin can be reduced and traction improved.
Improved traction:
- Leads to better vehicle control and safety
- Can prevent a vehicle becoming stuck in slippery conditions
- Reduces the strain on the powertrain
- Reduces the wear on the tires
- Uses less fuel or battery charge lost to otherwise slipping wheels
Unanswered Questions
Polestar says its system will determine the amount of steering input necessary to restore traction, but various questions are still left unanswered. The basic system seems to describe a drivetrain arrangement where the driven wheels are also the steered ones, ie. front-wheel drive, but we can see no reason why the system cannot be adapted to work on all wheels of vehicles with all-wheel steering.
What we’re more intrigued by is the fact that the oscillating action can be applied to individual wheels, and we don’t know how this is done in a vehicle that has the steered wheels connected via a traditional drag link, unless the action can be applied subtly via flexible mountings. Alternatively, it could have been designed for a steer-by-wire system that allows individual control of wheels’ steering angles.
