| 主权项 |
1. A calibration method for a multi-component force measuring spindle unit applied to a tire testing method,
wherein the tire testing method comprises:
a measurement step in which the multi-component force measuring spindle unit including a spindle shaft on which a test tire is adapted to be mounted, a housing for rotatably supporting the spindle shaft via a bearing unit, and two multi-component force measuring sensors which are disposed on locations spaced apart from each other along an axial direction of the spindle shaft, fixed to the housing, and capable of measuring loads exerted on the spindle shaft is used to measure the load exerted on the spindle shaft, anda calculation step in which a measured load vector consisting of the measured loads obtained in the measurement step is used along with a transformation matrix applied to the measured load vector, to thereby find an actual load vector consisting of actual loads acting on the tire, that comprises selecting, based on a plurality of output values obtained from the two multi-component force measuring sensors, the measured load vector consisting of five components fx1, fx2, fz1, fz2 and fy1+fy2, and applying a transformation matrix to the selected measured load vector, to thereby find the actual load vector consisting of n components where n<5 is/are selected from components of the actual loads (Fx, Fy, Fz, Mx, Mz) acting on the tire, where fx1, fy1, and fz1 are components of the measured loads in an x axis direction, a y axis direction, and a z axis direction, respectively, which are obtained from one of the two multi-component force sensors, and fx2, fy2, and fz2 are components of the measured loads in the x, y, and z axis directions, respectively, which are obtained from the other one of the two multi-component force sensors, where the x axis direction is a tire traveling direction, the y axis direction is in the axial direction of the spindle shaft, and the z-axis direction is a tire loading direction, andwherein the calibration method comprises:prior to the calculation step, a calibration step ofapplying the actual load vector whose components are all known to the multi-component force measuring spindle unit in such a manner that five linearly independent test conditions are established, anddetermining the measured load vector based on the plurality of output values obtained, under the conditions, from the two multi-component force measuring sensors, andcalculating the transformation matrix, defined as at least one of a 5 by n matrix and an n by 5 matrix, which relates the determined measured load vector to the actual load vector whose components are all known, and defining the calculated transformation matrix as the transformation matrix for use in the calculation step, whereinthe two multi-component force measuring sensors are adapted to be capable of measuring at least a three-degree-of-freedom translation load exerted on the spindle shaft. |
