Abstract:

The load spectrum of commercial vehicle cab assembly is the key factor affecting the accuracy and computational efficiency of virtual fatigue prediction. In this article， key links such as road load spectrum collection and editing， high fidelity dynamic modeling， and virtual iteration are explored， in order to obtain accurate and efficient external point time-domain loads from the engineering application perspective. Firstly， the full path road load spectrum of the driver's cab assembly is collected from the actual vehicle in the test field， and the original data is normalized， split， and reassembled considering random errors to obtain a statistically strong total damage target in the test field. Then， using the principle of equal damage， 9 operating conditions and their number of cycles are optimized， which not only controls the error within 10%， but also increases the efficiency by 75%. Subsequently， based on the performance parameters of the measured damping components， a high fidelity rigid flexible coupling dynamic model of the cab is established， and the accuracy of the model is verified through a 7-channel road simulation bench in the cab. Finally， the load decomposition of the optimal operating conditions is completed through virtual iteration， with an iteration error of less than 10%. Based on the above optimization and decomposition of the external connection point load， the virtual fatigue calculation of the cab body is efficiently completed， and the failure of the cab welding points is accurately predicted， which has a high degree of consistency with the durability test results of the road simulation bench， providing strong technical support for the design and optimization of commercial vehicle cabins.

Key words: accelerated editing of load spectrum, damage equivalence, virtual iteration, load extraction, virtual fatigue