Researcho n a directional control technique which steers the rear wheels along with the front ones has been reported in a series of papers since the 7th International Technical Conference on Experimental Safety Vehicles.

These fundamental studies have led to the development of a new four wheel steering system that varies the steer direction and angle of the rear wheels, depending on the steering wheel input. Among its features are decreased delay of steering response at high speed and decreased minimum turning radius at low speed.

This paper describes the basic principles of this new four wheel steering system, as well as its design and operation. It also discusses the results of tests of system function conducted under various operating conditions over a range of speeds, to demonstrate the benefits of installing this system in a vehicle.