Dynamic study of a high-performance vehicle seat: Modal analysis and Sled tests

Nowadays, one of the most important aspect throughout the design of any component on a vehicle is the safety of the passenger. During the homologation path, many tests are carried out to satisfy complex regulations, which force manufacturers and designers to introduce active and passive safety systems. In general, this type of tests involves the destruction of the device under investigation, with resulting economic costs. For this reason, the design process is followed by a simulation process, to investigate the needed aspects in a more efficient way. The purpose of this thesis is to give an example of this method from the simulation point of view, applied on a seat for a high performance vehicle. At first, a brief introduction about the current legislations and consumer tests is presented. Then, a description of the seat and its corresponding numerical model is given, with a focus on its characteristic to have the main structure of composite, for the best performance with lowest weight. The core of the work starts with modal analysis, used to have a general overview on the behaviour of the system, and to underline possible problems of vibrations during operation. After that, the work deals with sled tests, considering the cases of front and rear crash. The goal is to verify the seat from the structural point of view, avoiding any collapse on the main composite frame. At the end, the results are analysed more in detailed: the evolution of the test, the energetic balance and the added mass are shown to validate the simulations; weight is compared between the starting and the final models; the decelerations measured on the dummy are reported to evaluate physical damage on the driver and compared to the limits given for homologation.