Automatic steering system for vehicle

Abstract

An automatic steering system that can detect the steering operations of a driver during an automatic steering control operation in order to reliably discontinue the automatic steering control operation. The automatic steering control operation is discontinued if the driver spontaneously carries out a steering operation during an automatic steering control operation and if a steering torque equals to or is larger than a reference steering torque. When the steering torque equals to or is larger than the reference steering torque for at least a predetermined time, the automatic steering control operation is discontinued. Interruptions to the automatic operation by an instantaneous increase in steering torque due to a factor other than the steering operation provided by the driver, such as noise, can be eliminated. Furthermore, the reference steering torque or the predetermined time is changed in accordance with the frequency of an input steering torque, the vehicle speed, the steering angular speed, or the steering angular acceleration or the locus of movement of the vehicle.

Dependencies are inferred from the claim text.