Study On The Method Of Analysis Of The Road Load Signals Measured On The Proving Ground

This paper focuses on studying the method for analyzing the rear axle load signals of a minibus measured on the Hainan proving ground.The locations for sticking the strain gauges were properly determined,strain gauges stuck and the rig static calibration test performed in SAIC GM Wuling Automobile Co.,Ltd..The six-component wheel force transducers were also mounted on the vehicle tested.The road durability drive tests were done on the Hainan proving ground,with the stain signals and the wheel six-component load signals measured.The static rear axle finite element model was constructed by use of HyperMesh software.RADIOSS software was used to do the static analysis of the model.The obtained strains were compared with the static calibration results,which shows that the errors of the strains calculated with the finite element model were all smaller than 20%,indicating that the accuracy of the finite element model is comparatively high.Two dynamic finite element models of the rear axle were constructed based on the static finite element model of the rear axle above,in which the three-component force and six-component load signals were taken as the input signals,respectively.The modal transient analysis method was applied to calculate the strain time histories of the model elements corresponding to where the strain gauges were stuck.The strain signals obtained with the dynamic finite element models of the rear axle were compared with the corresponding signals measured on the Hainan proving ground,which shows that the reproduction accuracies of the strain signals of the strain gauges whose axes are parallel to the axle axis,obtained with the two dynamic models,are comparatively high,with the accuracies of the six-component loading model a little bit higher than those of the three-component loading model.But,the reproduction accuracies of the strain signals of the strain gauges,between the axis of each of whom and the axle axis there is an angle of 45 degrees,are not good.The nominal stress method was applied to calculate the fatigue damages of the strain signals obtained with the rear axle dynamic finite element models above and measured on the proving ground.The fatigue damages obtained were compared with each other,indicating that the fatigue damages of the calculated strain signals of the strain gauges whose axes are parallel to the axle axis are comparatively close to the fatigue damages of the corresponding measured signals and the engineering analysis requirement can be met.Thus,the dynamic finite element models constructed have reached the engineering application level in calculating the fatigue damages in the locations where the strain gauges whose axes are parallel to the axle axis are stuck.