Steer-by-wire steering system and method

A steer-by-wire steering system for a vehicle, comprising:

• a steering wheel,
• a first steering-angle sensor configured to directly measure an absolute steering angle of the steering wheel, the first steering-angle sensor being electrically powered via an actuator unit of the steering system;
• wherein the actuator unit is configured to set a wheel setting angle at the vehicle wheels,
• a steering unit comprising a steering actuator for applying torque to the steering wheel;
• a second sensor comprising a position sensor of the steering actuator, the second sensor being configured to derive a steering-angle of the steering wheel based on a position of the steering actuator,
• a processing logic configured to:
• use a steering-angle signal from the first steering-angle sensor during operation, and
• use the steering-angle signal derived from the position of the steering actuator via the second steering-angle sensor when the first steering-angle sensor fails, and
• two processing paths, including a first processing path and a second processing path, each comprising its own processing logic, actuator unit and position-sensor based steering-angle acquisition,
• wherein the first processing path determines a wheel-setting angle requirement ahead of the second processing path during normal operation, and
• wherein the steering angles determined by the position sensors of the respective processing paths are cross-checked against the output of the first steering-angle sensor of the second processing path to identify a faulty position sensor.