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The analysis of the vehicle crash performance is of great meaning in the vehicle design process. Due to the complexity of vehicle structures and uncertainty of crashes, the analysis of vehicle crashworthiness is generally depending on the researchers' experiences. In this paper, different deformation modes of energy absorption components are studied. More specifically, the bumper, crash box, the front longitudinal beam and the engine/firewall have different frequency characteristics in the deformation process. According to these characteristics, it is possible to identify the performance of each component in the crash process of assembled structures. To achieve this goal, the crash response of the passenger cabin is decomposed by the time-frequency transformation. Different frequency components exist mainly in a specified period of the crash process.

In this paper, we focus on the active vehicular suspension controller design. A quarter-vehicle suspension system is employed in the system analysis and synthesis. Due to the difficulty and cost in the measuring of all the states, we only choose two variables to construct the feedback loop, that is, the control law is a static-output-feedback (SOF) control. However, the sensor reduction would induce challenges in the controller design. One of the main challenges is the NP-hard problem in the corresponding SOF controller design. In order to deal with this challenge, we propose a two-stage design method in which a state-feedback controller is firstly designed and then the state-feedback controller is used to decouple the nonlinear conditions. To better compensate for the varying vehicle load, a robust load-dependent control strategy is adopted. The proposed design methodology is applied to a suspension control example.