Ride Comfort Study On Heavy_duty Commercial Vehicle Using Rigid-elastic Coupling Model

This article studies on the ride comfort of commercial vehicle and combines the"research on optimization and matching design of commercial vehicle". The study content of this article is relate to multi-body dynamic, optimization design and Timoshenko theory etc. in this paper, based on some commercial vehicle, the study is carried out.The templates of front suspension, midele suspension, rear suspension, steering, powertrain and mount of the pawertrain are built. In the process of building front suspension, the research of building leafspring is carried out, in the same time the orthogonal test and the extreme difference analysis are performeced. From the analysis of stiffness characteristics, the leafspring model can quickly established through parameter adjustment. In order to establish more precise model, the flexible bodies are considered. In this paper, the frame and cab are considered into flexible body, then the rigid full vehile and rigid-elastic models are built. After the model building, the simulations of the models are performed according to the national standard. The virtual road is edited in MATLAB according to the triangular waveform superimposing methord. The simulation calculations are carried out in FEA software Hypermesh and muli-body dynamic software ADAMS.According to the national standard GB/T4970-1996, the virtual full-vehicle models should be driven straightly on the national road level B, the travel speed should from 40km/h to 100km/h with an interval of 10km/h. the acceleration curves of the floor in the time domain can be gotten after the simulation, the PSD (power spectral density) of the acceleration can be gotten through the FFT transform, these calculations were carried in postprocessor of the ADAMS. Via the method of one third octave, the calculation program was edited in MATLAB. Based on the program, the weighted RMS (root mean square) of three directions are calculated. Then the value of weighted RMS of the floor was calculated. Through the comparation of different models, the dffect to the ride comfort of flex body in discussed. It is a trend to consider some important parts of the vehicle into flex body and analysis the rigid-elastic coupling model in the future. There will be more widely application prospect in coupling simulation area.