Brake-to-steer technology gets smarter, covers all autonomy levels
Originally developed to provide driver safety through an additional layer of directional control for highly automated and fully autonomous vehicles, the BtS technology has now been enhanced to cover and improve backup safety layers for all variants of Electric Power Steering (EPS) and Steer-by-Wire (SbW) systems and across all SAE levels of driving automation (levels 1 – 5). The developer company, CNXmotion, is a joint venture of automotive suppliers Continental and Nexteer.
Besides support for the autonomy levels 4 and 5, the company has added two new features: Driver effort support (SAE Levels 1-3), and steer-by-wire support for all autonomy levels from 1 to 5. “These new brake-to-steer software functions further enable safety redundancies across all electric power steering applications and SAE driving levels without the cost and complexity of additional hardware,” said Greg Katch, General Manager, CNXMotion.
EPS systems are designed with multiple protective layers to ensure the steering safety net is always on. When paired with a traditional EPS system, BtS Driver Effort Support adds another safety layer and can provide up to an additional 25% reduction in torque. While steering traditionally manages the lateral control of a vehicle, BtS enables the braking and powertrain systems to contribute to lateral control to reduce steering efforts when necessary.
Steer-by-Wire Support (SbW) replaces the mechanical steering connection between the hand wheel and road wheels with algorithms, electronics and actuators. In this type of steering system, the BtS SbW Support function adds another safety layer by translating the driver’s steering inputs into brake system control of the vehicle’s lateral motion.
“Brake-to-steer’s expanded software functions highlight how collaboration through our CNXMotion joint venture with Continental leads to innovation in motion control solutions and further enhances the steering safety net for all assisted and automated driving levels,” said Robin Milavec, President, Chief Technology Officer (CTO), Chief Strategy Officer (CSO) and Executive Board Director, Nexteer Automotive. “When combined with our advanced steering systems like steer-by-wire or high availability EPS, brake-to-steer provides OEMs with a cost-efficient, flexible way to add yet another layer of safety and redundancy.”
Brake-to-steer leverages the vehicle’s existing steering, braking and powertrain systems. The portable software functions can reside on an existing controller, eliminating the cost of any additional hardware.
According to the developer company, it enhances system’s flexibility by providing an additional layer of vehicle safety and redundancy on all vehicles with EPS and SbW. The three BtS software functions cover all types of vehicles with or without a driver.
CNXMotion was established as a joint venture between Continental and Nexteer Automotive in 2017 to innovate motion control solutions for advanced applications and accelerate R&D activities for the parent companies. The company employs about 30 people in its state-of-the-art facility located in Grand Blanc, Michigan, U.S.