| 摘要 |
<P>PROBLEM TO BE SOLVED: To improve an operation feeling of a steering system with a variable rotation transmission ratio. <P>SOLUTION: The steering system includes: an operation-side shaft rotating by control force; a turning-side shaft located on a wheel side of the operation-side shaft; a rotation transmission mechanism which transmits rotation of the operation-side shaft to the turning-side shaft; a torque detector which detects a rotational torque of the turning-side shaft; an assist device which assists a wheel turning; and an assist power control device which controls an operation of the assist device. In the steering system, the assist power control device estimates the control force on the basis of the rotation transmission ratio from the rotational torque of the turning-side shaft, decides a target assist power on the basis of the control force, and controls the operation of the assist power device on the basis of the target assist power. Such a control causes the target assist power to be decided on the basis of the control force even if the rotation transmission ratio varies, and the operation feeling can be kept excellent. <P>COPYRIGHT: (C)2011,JPO&INPIT |
