Patent ID: 8073593
Filing Date: 2011-12-06
Classification: B62D

Abstract:
1. A vehicle steering apparatus comprising: a variable transmission ratio device provided in a steering transmission system between a steering wheel and a vehicle wheel, wherein the variable transmission ratio device varies a ratio of a tire angle of the vehicle wheel to a turning angle of the steering wheel, by superimposing a first steering angle of the vehicle wheel based on operation of the steering wheel on a second steering angle of the vehicle wheel based on actuation of a motor mounted to a vehicle; and control means for controlling actuation of the variable transmission ratio device, wherein the control means executes an active steering control in which the control means automatically changes the second steering angle so as to stabilize an attitude of the vehicle, and wherein the control means starts the active steering control when a slip angle differential value is equal to or greater than a predetermined threshold value for the slip angle differential value, a sign of the slip angle differential value is identical with a sign of a yaw rate, a sign of the steering wheel turning angle is identical with a sign of a steering wheel turning speed, and a vehicle speed is equal to or greater than a predetermined threshold value for the vehicle speed.