| 摘要 |
PROBLEM TO BE SOLVED: To provide a vehicle steering device which detects the malfunction of a transmission ratio variable device with higher accuracy. SOLUTION: A microcomputer 21 has a position control computation part 28 for executing feedback control computation to make an ACT angleθta as an actual value follow an ACT command angleθta* as a target value. The position control computation part 28 varies a F/B gain to be used for the computation to be a lower value as a vehicle speed V is lower and to be a higher value as the vehicle speed V is higher. The microcomputer 21 has a malfunction detection part 34 for detecting the malfunction of the transmission ratio variable device 8 by comparing a deviationΔθta as the base of the feedback control computation with a threshold value. The malfunction detection part 34 changes the threshold value to be used for the malfunction detecting determination, to a lower value as the vehicle speed V is higher. COPYRIGHT: (C)2008,JPO&INPIT |
