Caracterisation et modelisation d'un vehicule tout terrain et de ses tampons d'ancrages faits d'elastomeres

The purpose of this Masters Thesis is to model an all terrain vehicle (ATV) in order to design a vibration energy harvesting device for engine mounts. Such a device needs to be optimized under known environmental conditions to work properly and to maximize the harvested energy. The ATV was modeled in a Finite Element Analysis (FEA) software in order to simulate the vibration loads and responses on the engine mounts and on the harvesting device. Information about the environment, such as induced forces and corresponding accelerations were needed in order to validate the ATV model and run simulations with the real inputs. A test bench was built in order to characterize the vehicle and its components. Rubber characterization was performed to simulate the hyperelastic and viscoelastic behaviors in the FEA software. Acceleration measurements were taken to identify the movement of the vehicle when excited by the engine. A modal analysis was performed experimentally to find the natural frequencies and mode shapes of the structure. A new method using force sensors (CF) has been developed to identify the forces exerted by the engine. This method consists in measuring the forces transmitted to the mounts and the accelerations at the mounts. Transmitted forces and corresponding inertia vectors were summed to identify the induced forces. This method was compared with the existing Frequency Response Function (FRF) method. The results achieved with the new developed method were satisfying when compared with the literature. The FEA model was run and improved in order to meet the identified natural frequencies, mode shapes and response spectra measured on the test bench. The results were satisfying according to the natural frequencies and mode shapes, but the model still needs improvement to match the response spectra.