| 摘要 |
<p>PURPOSE:To carry out switchover to manual steering without suddenly changing the steering feeling of a driver by gradually reducing assistant torque at a defined reduction coefficient based on a former steering torque data at the time of detecting the abnormality of a torque sensor. CONSTITUTION:At the time of starting the operation of a vehicle by turning on an ignition switch IG, a steering torque data is inputted into a CPU by inputting the output of a torque sensor 40 via an amplifier AMP1, a control compensation circuit PID and an A/D converting circuit AD. The abnormality of the torque sensor 40 is detected by comparing the output of the torque sensor 40 inputted via the AMP 1 with a steering torque inputted via the PID, while also detecting the abnormality of the torque sensor 40 by a sensor abnormality detecting circuit SA from the output of the sensor 40. At the time of detecting the abnormality of the sensor 40, control is carried out so as to gradually reduce an assistant torque at a defined reduction coefficient based on a former steering torque while referring to a hysteresis table.</p> |
