Patent ID: 9046457
Filing Date: 2015-06-02
Classification: B60G,B60T,B60W,G01N

Abstract:
1. A road surface condition estimating apparatus comprising: a reception means for receiving the wirelessly transmitted data of a vibration level or a vibration level computed value from a road surface condition estimating tire; and a road surface condition estimating means for estimating a road surface condition based on the vibration level or the vibration level computed value; and the road surface condition estimating tire comprising: a tire vibration detecting means disposed on the air chamber side of an inner liner in a tire tread area, the tire vibration detecting means detecting the vibration of a tire of a running vehicle; a pre-trailing domain signal extracting means for extracting signals of the pre-trailing domain, which is a domain before a trailing position estimated from a peak position of said tire vibration detected by said tire vibration detecting means; a post-trailing domain signal extracting means for extracting signals of tire vibration in the post-trailing domain, which is a domain after the trailing position estimated from the peak position of said tire vibration detected by said tire vibration detecting means; a frequency analysis means for analyzing the frequencies of said signals extracted by the pre-trailing domain signal extracting means and signals extracted by the post-trailing domain signal extracting means and obtaining a frequency spectrum in the pre-trailing domain and a frequency spectrum in the post-trailing domain; a vibration level calculating means for calculating a vibration level of a frequency band, the lower-limit frequency of which being 0.5 kHz or above and the upper-limit frequency of which being 4 kHz or below, from the obtained frequency spectrum of the post-trailing domain obtained by the frequency analysis means, and a vibration level of a frequency band, the lower-limit frequency of which being 2 kHz or above and the upper-limit frequency of which being 10 kHz or below, from a frequency spectrum of the pre-trailing domain obtained thereby; a means for calculating a vibration level computed value using said calculated vibration level in the post-trailing domain and vibration level in the pre-trailing domain; a means for wirelessly and automatically transmitting data of the vibration level or vibration level computed value to the vehicle body side; and a transmission means for wirelessly and automatically transmitting information of the estimated road surface condition to another vehicle automatically, wherein the frequency band for calculating the vibration level is higher in pre-trailing domain than the band in the post-trailing domain.