Vehicle steering apparatus

Abstract

A vehicle steering apparatus that can prevent a large returning torque from acting when a steering wheel is turned. Through processing of an assist control program, rotational torque (assist torque) of an electric motor is calculated by adding returning torque g*Trto to turning torque Tc (in actuality, subtracting the returning torque g*Trto from the turning torque Tc). The electric motor is driven and controlled in accordance with the calculated assist torque. When the steering torque is large, the calculated returning torque gain g decreases, and therefore, the returning torque g*Trto decreases or becomes zero. With this control, the greater the force (torque) required to operate the steering wheel, the smaller the influence of the returning torque, and steering feel at the time of turning the steering wheel is improved.

Dependencies are inferred from the claim text.