Abstract: A control device for a steer-by-wire type vehicle calculates a target turn angle being represented as a function of a steering angle of a steering wheel, and controls a turning device such that a turn angle of a wheel becomes the target turn angle. A variation range of the steering angle includes: an effective steering range in which the steering angle is an effective maximum steering angle or smaller; and an adjustment steering range in which the steering angle is between the effective maximum steering angle and a predetermined maximum steering angle. The target turn angle calculated according to the effective maximum steering angle is an effective maximum turn angle. The control device variably sets the function according to a road surface condition such that the effective maximum turn angle in a case of a low-? condition is smaller than that in a case of a high-? condition.

Abstract: A control device for a steer-by-wire type vehicle calculates a target turn angle being represented as a function of a steering angle of a steering wheel, and controls a turning device such that a turn angle of a wheel becomes the target turn angle. A variation range of the steering angle includes: an effective steering range in which the steering angle is an effective maximum steering angle or smaller; and an adjustment steering range in which the steering angle is between the effective maximum steering angle and a predetermined maximum steering angle. The target turn angle calculated according to the effective maximum steering angle is an effective maximum turn angle. The control device variably sets the function according to a road surface condition such that the effective maximum turn angle in a case of a low-? condition is smaller than that in a case of a high-? condition.

Abstract: A travel control device for a vehicle has a steered angle varying device 14 or a by-wire type steering device 96 which modifies a relationship of steered angle of steerable wheels to steering operation amount by a driver. When the control device decides that vehicle trajectory control is to be initiated or renewed, it calculates a target steered angle of the steerable wheels for driving the vehicle along a target trajectory which is required for the vehicle to arrive at a target arrival position in a target traveling direction on the basis of steering operation amount by a driver and vehicle speed at a time point of the decision. The control device controls the steered angle of the steerable wheels according to the target steered angle in feed-forward or feed-back manner.

Abstract: A travel control device for a vehicle has a steered angle varying device 14 or a by-wire type steering device 96 which modifies a relationship of steered angle of steerable wheels to steering operation amount by a driver. When the control device decides that vehicle trajectory control is to be initiated or renewed, it calculates a target steered angle of the steerable wheels for driving the vehicle along a target trajectory which is required for the vehicle to arrive at a target arrival position in a target traveling direction on the basis of steering operation amount by a driver and vehicle speed at a time point of the decision. The control device controls the steered angle of the steerable wheels according to the target steered angle in feed-forward or feed-back manner.

Abstract: When it is determined that the torque output from the electric motor abnormally fluctuates or the torque output from the electric motor varies between clockwise and counterclockwise turning operations of the driver's steering wheel, the steering assist control is continued if the vehicle speed v is equal to or lower than the reference speed v0. In this case, the width of the dead band of the steering torque in the assist map used to calculate the target assist torque is increased. Thus, only in a case where the vehicle is moving at a low speed and the driver's steering wheel is operated with a great force, the steering assist torque is produced to alleviate the burden on the driver. In the other cases, the electric motor is stopped to minimize a sense of discomfort in the steering operation.

Abstract: When it is determined that the torque output from the electric motor abnormally fluctuates or the torque output from the electric motor varies between clockwise and counterclockwise turning operations of the driver's steering wheel, the steering assist control is continued if the vehicle speed v is equal to or lower than the reference speed v0. In this case, the width of the dead band of the steering torque in the assist map used to calculate the target assist torque is increased. Thus, only in a case where the vehicle is moving at a low speed and the driver's steering wheel is operated with a great force, the steering assist torque is produced to alleviate the burden on the driver. In the other cases, the electric motor is stopped to minimize a sense of discomfort in the steering operation.

Abstract: An adjusting mechanism in a control valve assembly for a power cylinder in a power-assisted steering system of an automotive vehicle for adjusting a steering effort to be applied to a steering wheel placed in a neutral position, wherein the adjusting mechanism is provided with an adjusting-element located outside a housing of the control valve assembly to be operated for adjusting a load applied to the components of the control valve assembly.