Patent ID: 7677076

Claim:
An angular velocity sensor diagnosing device for use in a movable body, the angular velocity sensor diagnosing device comprising: an angular velocity sensor unit including two angular velocity sensors, each of the two angular velocity sensors including a respective oscillator having a shaft portion and an oscillatory portion, the two angular velocity sensors being arranged such that the shaft portion of each respective oscillator is not in parallel with an XY-plane defined by an X-axis and a Y-axis of three orthogonal axes; a first failure judging circuit for judging a failure of one angular velocity sensor of the two angular velocity sensors the judgment of the failure of the one angular velocity sensor depending on whether or not a detection value of an angular velocity about a Z-axis detected by the one angular velocity sensor is outside a tolerance range of a detection value of an angular velocity about the Z-axis detected by another angular velocity sensor of the two angular velocity sensors; and a second failure judging circuit for judging a failure of the another angular velocity sensor by comparing the detection value of the angular velocity detected by the another angular velocity sensor with an angular velocity calculated by a sensor that is mounted in the movable body and derives the calculated angular velocity from (i) a speed of the movable body, (ii) a steering angle of the movable body, and (iii) acceleration of the movable body.