| 摘要 |
PROBLEM TO BE SOLVED: To estimate road surface gradient accurately in detail even if output variation occurs to a motor.SOLUTION: When calculating a road gradient &thetas; on the basis of forward-reverse acceleration generated in a vehicle, in the vehicle at least including a motor that outputs drive force for traveling, a change amount &Dgr;Tm that is temporal change in motor torque Tm substantially affecting the forward-reverse acceleration is detected. In a case where the change amount &Dgr;Tm in the motor torque is equal to or more than a threshold &Dgr;Tc, variation in an input value of the forward-reverse acceleration used for calculating a road gradient &thetas; is suppressed, and a road gradient &thetas; is calculated on the basis of the input value with the variation suppressed. |
