Steering system

A steering system provided in a vehicle and configured to steer a pair of wheel mechanically disconnected from a steering operation member operable by a driver, the steering system comprising:

• an operation amount sensor configured to detect an operation amount of the steering operation member by the driver;
• an operation amount estimator configured to estimate an operation amount of the steering operation member which is not based on a detected value of the operation amount sensor;
• a steering mechanism including at least one steering actuator and configured to steer the pair of wheels by an operation of the steering actuator;
• and
• a steering controller configured to control a steering angle of the pair of wheels by controlling the at least one steering actuator based on the operation amount of the steering operation member,
• wherein the steering controller is configured to:
• control the at least one steering actuator based on an estimated operation amount when an operation amount estimation system including the operation amount estimator is normal and
• control the at least one steering actuator based on a sensor operation amount when the operation amount estimation system is abnormal,
• the estimated operation amount being an operation amount of the steering operation member estimated by the operation amount estimator, the sensor operation amount being an operation amount of the steering operation member detected by the operation amount sensor.