The Study Of Analysis Technology Of Vehicle Axle Housing’s Fatigue Life Under Road Excitation

Axle housing is an important part of automobile axle. It has a complex stress condition and a harsh working condition, so it has the most possibility to failure. In the process of driving, the excitation from the road roughness would not only cause resonance damage of the axle housing, but also can cause fatigue failure of the axle housing. Therefore, it is necessary to do modal analysis for the axle housing to get its natural frequency and to analyze whether it can damage that caused by resonance. And it is necessary to predict the fatigue life of the axle housing when the vehicle is driving on the complex road condition. In this paper, the excitation load was obtained by a method of convenient operation, low cost and reliable data. The research object of this paper is the axle housing of a mini car, using the finite element method combined with experimental method to ensure this research has the experimental support. The followings are the main research work of this paper:Firstly, the finite element model of this driving axle housing was established, and the modal analysis was done to get its natural frequency in this paper. Its natural frequency was used to compare with the road excitation frequency to analyze whether the axle housing was able to resonate.Secondly, the hammering model test was done to the entity of this axle housing to verify whether the above conclusion was correct or not and the availability of this finite element modal.Then, the acceleration sensors were used to collect the acceleration signal on the axle housing generated due to the impact of the load when the car driving on the washboards road, fish scale hole road, and twisted road. Then built and solve the tire-suspension system differential equation and used the acceleration signal to solve to get the force signal of this axle housing.Finally, this force signal obtained by the above solution was acted as the excitation load, the RADIOSS module from Hyperworks was used to do fatigue analysis of the axle housing and to calculate the driving distance when the car driving on these three kinds of composite road which is more in line with its driving conditions. Then proposing a improvement program according to the results and verifying the feasibility of this improved scheme.