First vehicle with 4WS system was 1987 Honda Prelude. It was a mechanical joint with nifty cinematic connections between tie rods of front and rear wheels. Right after the appearance of this model whole Japanese market just exploded with full-steering cars. Mitsubishi released four wheel steering Galant and Sigma, Mazda added 4WS to it's 626 model and even Toyota Celica make it's rear wheels move two years later.

The four-wheel steering system has three goals. First is to make the steering sensible to the steering wheel turning intensity. It gives the possibility to have a "sharp" steering wheel at the city and soft the highway. The second goal is to decrease the turning radius and make parking more comfortable. The last goal is to increase the vehicle stability during the maneuvers at the high speed.

The fourth generation of Honda Prelude has the next generation of the 4WS system introduced in 1991. Rear wheels are turning using the electronic drive into the rear suspension. The electric drive is controlled by computer who gets the information about the steering wheel position, front and rear wheels turn angel and current vehicle speed.

4WS system is working in two modes. At low speed the rear wheels are turning in the same direction as the front wheels. It allows increasing the steering radius with same steering wheel turning angle. It means that the steering wheel becomes "sharper". For example if the front wheels would be turned maximum into left the rear wheels would be turned into right by the 8% of the front wheels turn. Steering diameter decreases by 15%.

And vise versa. At the high speed the 4WS system will turn rear wheels by low angel the same direction as the front wheels. It is very helpful while taking over at the highway. The car will move by the arc of less curvature and bigger radius. The torque turning the car around the vertical axis will decrease. That means the vehicle stability will rise and there will be lower drifting risk.