Abstract: A vehicular steering control apparatus controls the wheel steering amount of wheels based on a steering angle and an assist angle obtained by multiplying a steering speed by a gain. If the amount of power control differs between the left wheel and the right wheel, the value of gain is increased. The amount of power control includes, for example, the amount of braking control and the amount of drive control. If the assist angle is increased by increasing the gain, the magnitude of the wheel steering amount relative to the steering angle increases, so that a driver can correct the orientation of the vehicle body by performing a small amount of steering operation.

Abstract: A base transmission ratio Gbase is determined according to the vehicle speed and a compensation amount &agr; is determined for each of feed steering case and return steering case during acceleration/deceleration. Based on this, the transmission ratio G of a transmission ratio varying mechanism is set as G=Gbase+&agr;.

Abstract: Target rotational speed of servo motor 31 is set based on steering speed &thgr;hv detected by steering speed sensor and transmission ratio G set according to a running condition, and speed of servo motor is controlled so that rotational speed &thgr;pv of servo motor detected by rotational speed sensor may agree with the target rotational speed.

Abstract: A hand-off state determination section 73 estimates torque Th exerted on the steering handle by a driver. When the steering handle is in the hand-off state in which the torque is small, switching is effected to the side of compensator 75 having smaller gains set, so as to stabilize a steering control system.

Abstract: In a vehicle steering apparatus having a variable gear ratio unit arranged midway along a steering transmission system for connecting a steering wheel and tires to change the transmission ratio, and an ECU for variably controlling the variable gear ratio unit in accordance with the state of a vehicle, the variable gear ratio unit includes a motor controlled by the ECU, and a reducing mechanism which has a transmission ratio for allowing to maintain the steering angle of the steering wheel with respect to an RF reverse input and transmits the rotation of the motor to the output side. Even if a reverse input acts from a tire side during traveling, the relationship between the steering amount of the steering wheel and the turning amount of the tire can be kept unchanged.

Abstract: A vehicle steering apparatus having a variable gear ratio unit arranged midway along a steering transmission system for connecting a steering wheel and a tire to change a transmission ratio upon driving a motor includes a connecting unit for stopping actuation of the variable gear ratio unit in accordance with an external signal to connect the input side of the variable gear ratio unit which is connected to the steering wheel to the output side of the variable gear ratio unit which is connected to the tire. Even if a reverse input acts from a tire side during traveling, the relationship between the steering amount of the steering wheel and the turning amount of the tire can be kept unchanged.

Abstract: An object of this invention is to provide an electric power steering apparatus with good steering feeling. This electric power steering apparatus has a steering system for turning tires in accordance with manipulation of steering wheel, a power assist motor for assisting this turning of the tires by the steering system, a non-stage transmission with variable transmission ratios, interposed between the power assist motor and the steering system, and an ECU for controlling the transmission ratios of the non-stage transmission and for controlling the output of motor in accordance with the turning of the tires by the steering system.