| 摘要 |
<p>A control mode for a damping force characteristic is set to be a variable control when a product of the sum x b ' of sprung member speeds and a sprung-member-unsprung-member-relative-speed x s ' is positive. Accordingly, when the vibration in a middle/high frequency range is not being input to a suspension apparatus SP, an operation of a variable throttle mechanism 30 is controlled in such a manner that a step number representing the damping force characteristic of a damper 20 varies in accordance with a vibration state of a sprung member HA based on a Nonlinear H ˆž control theory. Further, when the product of the sum x b ' of sprung member speeds and the sprung-member-unsprung-member-relative-speed x s ' is negative, the control mode is set to be an operation prohibiting control. Consequently, when the vibration in the middle/high frequency range is being input to the suspension apparatus SP, the operation of the variable throttle mechanism 30 is prohibited, and an increase in the operation frequency of or in the operation amount of the variable throttle mechanism 30 is therefore suppressed. Accordingly, the durability of the variable throttle mechanism 30 is improved.</p> |
