PURPOSE: To execute quickly a correction in case when an operated neutral position is dislocated from an actual neutral position, and also to reduce a degree of the dislocation by selecting a sampling period in case of deriving a steering angle neutral position, to an appropriate value in accordance with a running state.
CONSTITUTION: This device is provided with a running state detector 1, a steering state detector 2 for outputting a signal corresponding to turning of a steering mechanism of a vehicle, a period selecting means 4 for selecting a sampling period based on a signal of the detector 1, a steering angle neutral position operating means 3 for calculating a steering angle neutral position in accordance with a sampling period based on a signal of the detector 2, and an actual steering angle operating means 5 for calculating an actual steering angle based on steering angle information based on a signal from the detector 2 and steering angle neutral position information from the operating means 3. In this state, a sampling period in case of deriving the steering angle neutral position based on the steering angle information detected by the detector 2 is selected in accordance with a running state of a vehicle, and even if the running state is varied, by always deriving a steering angle neutral position which is presumed to be correct, an actual steering angle is calculated from this neutral information and the steering angle information.
KUROKI JUNSUKE
AKATSU YOSUKE
