| 摘要 |
PROBLEM TO BE SOLVED: To precisely detect the abnormality of a yaw rate sensor without any erroneous detection. SOLUTION: On the basis of the difference between a right wheel speed detection value VWR and a left wheel speed detection value VWL, an estimated yaw rateϕobs is calculated. The estimated yaw rateϕobs and the detection yaw rateϕR of a yaw rate sensor 14 are high-pass-filter-processed. Their deviationΔϕis then found. When the deviationΔϕexceeds a threshold valueαfor an abnormality judgment time T or higher, the abnormality of the yaw rate sensor 14 is judged. At this time, whether a vehicle is in an acceleration state or a deceleration state is judged on the basis of the detection value XG of a lengthwise accelerometer 13. When it is in the acceleration state or in the deceleration state, a cutoff frequencyωC in a high-pass-filter- processing operation is set at a higher value as compared with a non-acceleration state and a non-deceleration state. A temporary increase in an estimated yaw rateϕobs', after the high-pass-filter-processing operation, generated in an acceleration and a deceleration caused by the tire diameter difference between a right wheel and a left wheel is converged quickly so as to prevent the temporary increase from being judged erroneously to be the abnormality of the yaw rate sensor 14. |
