Patent ID: 7668669
Filing Date: 2010-02-23
Classification: G01L

Abstract:
1. A method for estimating the magnitude of a back-and-forth-direction force exerted on a tire comprising: using a plurality of strain sensors fixed to a sidewall of the tire at circumferentially different positions around the rotational axis of the tire, each said strain sensor capable of outputting data on the magnitude of a strain occurred at the position of the strain sensor; reading the output data from the strain sensors when come to measuring positions, said measuring positions are a plurality of fixed positions predetermined around the tire rotational axis; in relation to each of the strain sensors at the respective measuring positions, calculating the back-and-forth-direction force as an intermediate result by the use of the data read from the strain sensor and a relational expression effectual for the measuring position at which the strain sensor is positioned, whereby a set of the intermediate results are obtained from the respective strain sensors; and computing a mean value of only the valid intermediate results or result so as to output it as the estimated magnitude of the back-and-forth-direction force.