Published October 18, 2012
By Philippe Crowe
Nissan unveiled yesterday the world’s first steering technology that allows independent control of a vehicle’s tire angle and steering inputs.
A conventional steering system directs tire movements by transmitting steering inputs to the tires via a mechanical link. Nissan’s next-generation steering technology reads the driver’s intentions from steering inputs and controls the vehicle’s tire movements via electronic signals.
It also has the benefit of being fully electric; doing away with traditional mechanical steering means less energy consumption.
According to Nissan, this system transmits the driver’s intentions to the wheels even faster than a mechanical system and increases the direct driving performance feel by quickly and intelligently communicating road surface feedback to the driver.
Per Nissan, the system controls and insulates the vehicle from unnecessary road-generated disturbances to deliver only the necessary performance feel to the driver. For example, even on a road surface with minor ridges or furrows, the driver no longer has to grip the steering wheel tightly and make detailed adjustments, so traveling on the intended path becomes easier.
Accompanying this next-generation steering technology, Nissan has also developed a camera-based straight-line stability system to further enhance on-center driving capability. This system is a world-first of accurate tracing technology in continuing driving as planned in the lane with small steering angle adjustments depending on road condition.
This camera-based system improves vehicle stability by making small input angle adjustments so the vehicle will accurately trace and continue as planned in the lane it is traveling. If the vehicle direction changes due to road surface or crosswinds, the system acts to minimize the effect of these conditions resulting in reduced steering input from the driver.
Using a camera mounted above the vehicle’s rearview mirror, the system analyzes the road ahead, recognizes the lane direction, detects changes in the vehicle’s direction, and transmits this information to multiple electronic control units as electronic signals. If a discrepancy occurs, the system acts to reduce the discrepancy by controlling the opposing force to the tire angle. By reducing the frequency of detailed steering input adjustments, which are a cause of fatigue on long drives, the driver’s workload is greatly reduced.
This next-generation steering technology’s high reliability is achieved by multiple ECUs. In the event a single ECU malfunctions, another ECU will instantly take control, and in extreme circumstances such as the power supply being disrupted, the backup clutch will act to connect the steering wheel and wheels mechanically, ensuring continued safe travel.
This technology will be equipped on select Infiniti models on sale within one year.
