Monday  |  Cottonwood  |  02:10 PM–02:30 PM

#7753, Bayesian Uncertainty Quantification in The Development of a New Vibration Absorber Technology

The essential requirements for the suspension strut of modern vehicles are high driving safety and high driving comfort. The control of the driver over the vehicle, and thus also the driving safety, can only be ensured if there is wheel-ground contact at any time. The driving comfort is influenced decisively by acceleration acting on the occupants. Thus, the suspension strut of a vehicle affects both driving safety and driving comfort. The adjustment of a classical shock absorber system leads to a compromise between driving safety and driving comfort. In contrast a dynamic vibration absorber is capable of reducing vibrations of the wheel in a defined frequency band without affecting the body acceleration. Therefore, energy of the accelerated wheel is redirected into the structure extension. The inertia of the fluid dynamic vibration absorber (FDVA) is translated by a hydraulic transmission and can therefore be built more lightly compared to a conventional dynamic vibration absorber.
Mathematical models of such a FDVA are utilized in order to predict its dynamic response under different boundary conditions. This helps to guarantee the desired functionality at an early design stage and thus ensure a safe design. However, such a prediction of the dynamic response is subject to model uncertainty.
The main focus of this paper is on model’s uncertainty resulting from model’s complexity. The model’s complexity is designed to be as simple as possible for optimization calculations.
Since development is often domain-specific, system and module boundaries must first be defined for the development process. For this purpose, the modules are cut out of the overall system. The boundaries of the model, in this case the FDVA, has first be found for a correct mathematical model but also for a correct experimental setup to get reliable empiric data. After this the proposed dynamic response of mathematical model will be investigated.
At a hydraulic transmission in an oscillating system, there are several approaches to modeling the oscillating flow and damping. Damping plays a decisive role in vibration absorbers. The occurring uncertainty of prediction of the dynamic response of the different models has to be quantified, especially if it represents a risk for vehicle occupants. Therefore Bayesian interval hypothesis-based method is used to quantify this uncertainty.

Nicolas Brötz   Technische Universität Darmstadt
Peter Pelz   Technische Universität Darmstadt