| 摘要 |
PROBLEM TO BE SOLVED: To provide a method capable of estimating a snow road on which a vehicle is traveling by further segmenting the snow road.SOLUTION: A tire circumferential vibration of a tire, a road surface temperature T, and a tire noise are detected by an acceleration sensor, a road surface thermometer, and a microphone, respectively. Band values P, P, and Pof a pre-stepping region R1, band values P, P, and Pof a stepping region R2, band values P, P, and Pof a pre-kicking region R3, band values P, P, and Pof a pre-kicking region R4, and band values P, P, and Pof a post-kicking region R5 are calculated from data on the tire vibration. A sound pressure level ratio Q=(P/P) that is a ratio of a band power value Pin a low frequency band to a band power value Pin a high frequency band is computed from data on the tire noise. A road surface state is estimated using the band values P, data on the road surface temperature T, the sound pressure level ratio Q, and data on a wheel speed. |
