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The increased adoption of downsized engines along with higher electrical demand is generating a challenge to the Front-End Accessory Drive (FEAD) system functioning and validation. One alternative to speed up the validation of potential design solutions is the in-vehicle experimental tests approach. Nevertheless, experimental data collection during in-vehicle FEAD evaluation imposes some challenges due to, for instance, packaging space constraints and sample rate required to capture the dynamic events during vehicle operation, among others. In order to overcome this limitation, the objective of this research is focused in the development of a customized test rig that emulates FEAD layout of an actual automobile in a simulated operating condition.

Vehicle alternator pulleys with one-way-clutch and vibration attenuation mechanisms have recently been adopted in modern vehicles in order to reduce or mitigate undesirable side effects of torsional vibrations generated by Internal Combustion Engines (ICE) during its normal operation. It is noticeable how excessive vibration can be particularly detrimental to the components of the Front-End Accessory Drive (FEAD) system. Increase of inertia forces due to the use of larger alternators along with the increase in torsional vibration amplitudes of downsized engines added up with lower idling speeds to reduce emissions have set a challenge for proper FEAD functioning and validation. In order to validate potential design solutions, in-vehicle experimental tests are an important approach. How to define an adequate test plan, execute test cycles and post-process bulk experimental data to assure proper assessment of alternator pulley alternatives is a key factor of success.

Increasingly research has been conducted lately towards reduction of both fuel consumption and gases emission in automotive vehicles propelled by Internal Combustion Engines. Among many initiatives, downsizing of those engines has been broadly adopted, arising side effects as increased vibration levels along Front-End Accessory Drive (FEAD) system. The present study focuses on the potential improvement of transmission efficiency and of vibration levels along FEAD by considering different layouts for the system. Multiple combinations of alternator pulley technologies and tensioner types are evaluated either during in-vehicle tests or in customized test rig that emulates vehicle FEAD in operating conditions. Specific transducers spred over the vehicle and at test rig assure the relevant data are captured for every layout arrangement investigated.