Steer-By-Wire – The Challenge of Angles and Torque

The introduction of Steer-by-wire systems for cars is believed to bring a wide range of advantages ranging from production simplifications to passive safety and advances in active safety. The intense work with autonomous driving has paved the way for redundancy and systems safety needed to introduce steer-by-wire to the broad market. This paper explores some of the fundamental aspects of mechanically disconnecting the driver and hand wheel from the vehicle and the road wheel, such as variable steering ratio and generation of haptic torque feedback. Simple strategies are developed and tested on test track in a prototype vehicle. Initial tests suggest that the simple strategies show promise.