Nissan's system does allow the steering effort to be customizable to provide steering effort ranging from that of a luxury car to that of a sports car. Since there is no mechanical link between the wheels and the steering wheel, any unwanted vibrations from the road can be isolated and will not be felt by the driver. The system also uses a series of cameras and sensors to help keep the car in the lane and can automatically correct the car even if there is a crosswind or road condition that could change the direction of the car: the overall benefit to the driver is the reduce fatigue. Just in case something goes wrong, the system does have backup systems and is still fitted with a mechanical link should there is a big problem.
How could this be useful to disabled drivers? For those that do not use altered steering, this could make driving a little bit easier. For drivers that use zero-effort steering or modified steering, this system could potentially make conversions cheaper since it could just take a little reprogramming to get zero effort steering. The cost of steering modifications could potentially be reduced since there is no mechanical linkage to connect to: the steering wheel can be whatever works for the disabled driver and all it needs to do is interact with the steer-by-wire system. Many of the systems used in custom steering systems for disabled drivers have been integrated into the Nissan's system, making it virtually as safe as the current AEVIT-like systems currently in use.
Check out the clip below to find out more about Nissan's steer-by-wire system. Enjoy!