Being the presumption method of presuming with front and back power

摘要

PROBLEM TO BE SOLVED: To improve estimation accuracy of forces applied to a tire by estimating while accurately separating each of the applied forces from a tire strain.SOLUTION: In this method of estimating forces applied to the tire, the estimation equations of fore-and-aft force Fx, vertical force Fz are determined as functions of synthetic variables Px(v), Pz(v) using sensor outputs V1, ..., Vn of tire strains. The synthetic variables Px(v), Pz(v) are determined from a prior weight load test as follows: (α) Letting loaded weights Fx, Fz and sensor outputs V1, ..., Vn measured when loaded be the variables, a plurality of sample data D are determined. (β) The sample data D are applied with principal component analysis to obtain factor loadings of first to k-th (k≥2) principal components of the variables Fx, Fz, V1, ..., Vn. (γ) A scatter diagram of the factor loadings is determined taking the first principal component and the second principal component as reference axes. (δ) In the scatter diagram, an orthogonal vector Fx' to the vector Fz and an orthogonal vector Fz' to the vector Fx are synthesized using at least two selected vectors selected from vectors V1, V2, ..., Vn, respectively. This synthesized orthogonal vectors Fx', Fz' are let to be the synthetic variables Px(v), Pz(v).