Patent ID: 8131426

Claim:
A vehicle steering system comprising: a first rotating member connected to a steering member; a second rotating member connected to a steering mechanism; a switching member that switches between a connected state where the first rotating member and the second rotating member are connected to each other and an unconnected state where the first rotating member and the second rotating member are unconnected to each other; a reaction force actuator that applies a steering reaction force to the steering member; a steering actuator that drives the steering mechanism in the unconnected state; and a control section that controls the steering actuator, the reaction force actuator, and the switching member, wherein the control section includes a steer-by-wire mode, a power steering mode, and a first transition mode for transition from the steer-by-wire mode to the power steering mode, in the steer-by-wire mode, the control section controls the steering actuator for steering while controlling the reaction force actuator for reaction force in the unconnected state, in the power steering mode, steering assist control is carried out with at least one of the steering actuator and the reaction force actuator as an assist unit in the connected state, in the first transition mode, the control section controls the reaction force actuator for reaction force in a transition period from the steer-by-wire mode to the power steering mode, and in the first transition mode, the reaction force actuator is controlled such that a reaction force generated by the reaction force actuator is gradually increased toward a target reaction force upon completion of switching of the switching member previously set or is held in a reaction force generated by the reaction force actuator before output of a switching signal.