During straight-line driving, the driver’s acceleration and braking maneuvers induce pitching motion of the vehicle body. Frequent attitude changes are prone to causing motion sickness of passengers and adversely affect the handling experience. To suppress this adverse pitch response, focusing on the problem of vehicle body pitch attitude control under driving and braking conditions, this paper conducted research on modeling and control algorithms based on a fully active suspension system, and verified the control effect through real-vehicle tests. Firstly, a four-degree-of-freedom vehicle pitch model was developed, with particular emphasis on the effects of suspension anti-dive and anti-lift characteristics, the location of the sprung mass’s pitch center, and the differences in the transmission paths of driving and braking forces. The model was validated via CarMaker co-simulations. Subsequently, a vehicle body attitude control algorithm based on feedforward-feedback architecture was designed, for which a nonlinear pitch model was used in place of real vehicle state feedback, achieving decoupling between the driving/braking force inputs and the disturbances caused by vertical road displacement. This approach effectively prevents road undulations and gradients from interfering with the suspension control force output. Furthermore, based on the control objective of zero pitch angle, a feedforward and PID feedback controller was designed, and an optimization method for the feedforward controller that is easy to implement in engineering was proposed, which resolves the issue of high-frequency chattering in the output force of the theoretical feedforward controller. Finally, real-vehicle tests were conducted on a prototype vehicle equipped with fully active suspension, and the results demonstrate that the proposed control strategy significantly attenuates vehicle pitch response under full-throttle acceleration and emergency braking conditions, reducing pitch angle RMS by up to 89.2% and 77.7%, respectively, thereby enhancing ride comfort and handling stability.

As one of the core components of electric vehicles, battery package has a critical impact on the overall performance of the electric vehicle. During the operation of electric vehicles, the battery package is constantly subjected to continuous impact from the road, causing fatigue damage to the battery package, which affects the safety of drivers and passengers as well as the performance of the whole vehicle. Taking battery package of electric vehicles as research object, this study established random vibration test method and calculation method for fatigue life of battery package. Firstly, it carried out frequency sweep analysis on Shaker table, fixture and battery package, and obtained the values of the acceleration sensors at shaker table surface, fixture unloaded end plate, and the connection end plate between battery package and fixture, which were consistent with the input frequency sweep acceleration values, verifying the effective transmission of the vibration signal and ensuring that the input vibration signal can be accurately transmitted to the battery package. After that, random vibration test of battery package was carried out. Cell performance testing, air tightness inspection, insulation resistance inspection, and resonance frequency inspection on the battery package were conducted and the damaged parts of battery package were obtained. The calculation method of battery pack fatigue damage was studied, and the battery box, battery module and battery pack were finely modeled. Based on the fine modeling, frequency response of battery package was analyzed. Based on the results of frequency response analysis and the random vibration load spectrum curve of the battery package obtained from the vehicle road spectrum acquisition test, and combined with the S-N curve of the battery pack material, random vibration fatigue life of battery package was analyzed under load spectrum by using Goodman fatigue life estimation method and Miner linear cumulative damage rule. The damage positions of battery package obtained from the test are in good agreement with the failure positions obtained from the analysis, which confirms the accuracy of the fatigue life calculation method proposed in this paper.