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The aim of this research is to present a new concept of adaptive crashworthiness system. Main objectives of the proposed system are to predict, control and adjust the impact characteristics to various conditions by decreasing the pre-designed crushing stiffness of the vehicle frontal deformation zone. According to the initial pre-crash parameters (velocity, mass, stiffness and overlap) the prospective system can select proper crushing force. In most basic approach each absorber has two levels of the crushing stiffness - high and low. De-stiffening feature is driven by pyrotechnic detachable connectors integrated in the frontal car structure, which can be destroyed causing disconnection of selected structural members, excluding them from the energy dissipation process. Pyrotechnical stiffness control can be activated in a very short time, sufficient to act during typical road accidents. Among other things, the presented idea can be used to solve mass compatibility problems.

Vibration of an exhaust tube with a non-linear fixing construction is analyzed. Numerical and laser holography investigation methods are used for the determination of vibration processes happening nearby the cylinder fixing areas. Obviously, the analyzed non-linear system can produce complex reactions even to harmonic excitations. The knowledge about such zones of “wrong” dynamic behavior may help to eliminate and reduce higher noise levels and extend the lifetime of the construction.

The dynamics of the vehicle is strongly dependent from the quality and interaction between its subsystems. The quality of assembly and mounting of bearings can effect the characteristics of the system, especially its dynamical properties. The assembly process of bearing joints requires rather high pressing forces. At the same time the accuracy of the assembled components must be controlled with extreme precision. Rather small deviations from the predefined limits can cause quite severe complications, - such as necessity of maintenance, or just problems with dynamical response of the subsystem, especially under heavier dynamic loads. The goal of the study was to evaluate the status of bearing joints assembly, and to optimize the process of mechanical integration. The control of the mounting forces was altered introducing the high frequency vibration excitation. The resulting effect decreased friction and static load forces in the joint under the assembly.