Random Analysis of Heavy‐Duty Vehicle Based on Rigid–Elastic Synthesis

Abstract

Heavy‐duty vehicles have the advantages of heavy load, long transportation distance and so on, and ride comfort is an important feature of heavy‐duty vehicles. Flexibility of the heavy‐duty vehicle body is an essential factor in ride comfort, and a three‐axle heavy‐duty vehicle is the main commercial vehicle in China. To comprehensively analyze flexibility of vehicle body, elastic natural characteristics of free‐free beam with equal cross sections are derived, and vibration energy of rigid–elastic synthesis of the beam is obtained. Because the vehicle body is regarded as a free‐free beam with equal cross section, a 10 degree‐of‐freedom rigid elastic synthesis mechanics model of the three‐axle heavy‐duty vehicle is established, and a mathematics model of this heavy‐duty vehicle is derived based on the model energy. The frequency domain analysis method for the rigid–elastic synthesis model of a three‐axle heavy‐duty vehicle is determined by Fourier transform. The formulas of vibration response for the three‐axle heavy‐duty vehicle are derived, and the calculation method for statistical properties of vibration response is given. In order to analyze the effect of body flexibility on ride comfort, the ride comfort of a three‐axle heavy‐duty vehicle is simulated according to both the rigid–elastic synthesis model and the rigid model of three‐axle heavy‐duty vehicle, and the simulation results are compared on a B‐grade road with a common speed of 70 km/h. The results show that rigid–elastic synthesis of the vehicle body has a greater effect on vertical accelerations of the vehicle body and a lesser effect on human vertical acceleration, working places of suspensions and relative dynamic loads of wheels under regular analysis. © 2020 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC.