“Steer-by-wire means the end of the mechanical connection between the steering wheel and the road wheels, with electronically-controlled actuators setting the steering angles and electronically-controlled force feedback to the driver’s steering wheel,” said Dr. Dieter Fehlings, engineering director for TRW’s European steering operations. “Steer-by-wire will be the enabler for fully integrated vehicle stability control systems, for collision avoidance systems, and one day, potentially, even for autonomous driving.”
According to Fehlings, the challenge for this technology is defining the fault tolerant electrical architecture with internal redundancies that enables the system, which has no mechanical connection between the steering wheel and the road wheels. TRW said it is now working to develop a system, based on the output from this project, that delivers advanced functionality enabled through a steer-by-wire system, such as variable steer ratio according to speed and a choice of driver feel, but at a cost viable for the mass vehicle market.
“Coupled with the introduction of brake-by-wire systems, the design of the chassis will be greatly simplified. Ultimately, there will be four equal corner modules that will be significantly lighter and easy to fit. Moreover, steer- and brake-by-wire are key enablers toward the integrated vehicle control systems that TRW is working toward,” said Alois Seewald, TRW Chassis Systems’ global director of research and development.