Road surface condition estimating method, vehicle control method, and road surface condition estimating apparatus

摘要

The condition of a road surface on which a vehicle is traveling is estimated accurately, using a tire having a general variable-pitch tire pattern for detection of a road surface condition. The tire for detection of a road surface condition has rows of blocks, the total number N of the circumferentially disposed blocks being 10 or more and the number n of lug grooves, each provided with a joining section connecting circumferentially adjacent blocks, being in the range of (N/2)≦n≦(N−5). The vibrations of the tire are detected by an acceleration sensor and are subjected to a rotational order ratio analysis by a rotational order ratio analyzing unit. And the road surface condition is estimated by comparing the amplitude P of the rotational order component of the tire vibrations extracted by a rotational order component extracting unit with a predetermined threshold value K.

主权项

1. A method for estimating a road surface condition,
comprising the steps of: detecting vibrations of a tire having a block pattern by a vibration detecting unit; performing a rotational order ratio analysis on the tire vibrations by a rotational order components extracting unit; and estimating a current road surface condition from an amplitude of a rotational order component of the analyzed tire vibrations by a road surface condition estimating unit, wherein the tire has at least one row of blocks and lug grooves, each lug groove being disposed between adjacent blocks of the row of blocks, the total number N of the circumferentially disposed blocks and corresponding lug grooves being 10 or more, wherein a number n of lug grooves are provided with a joining section connecting circumferentially adjacent blocks, a relation between n and the total number N satisfying the range of (N/2)≦n≦(N−5), and wherein the order of the rotational order component for estimation of the road surface condition is (N−n).