The Project Hypergears focuses on the development of innovative models, methods and tools to improve the design process of high-performance gears aiming to increase efficiency and reduce vibrations produced and noise radiated by power transmissions. Notwithstanding the large body of existing scientific literature, the topic remains of primary importance for the industry: for example, in the automotive sector, gear efficiency and transmission noise has become aspect of considerable importance because, in electric vehicles, the gearbox system is the main mechanical source of losses and noise. From scientific literature, the most commonly adopted modelling strategies can be classified in analytical, Finite Element, and multibody. Hypergears is focused on the development of a new methodology for the simulation of high-performance gears based on the concept of flexible multibody model. In particular, the main goal is to identify those parameters and constructive elements of gear pairs that are most relevant for the generation of vibration and noise. This goal is achieved through the development of simulation models to predict vibrations phenomena and evaluate the performance of the gears in complex scenarios. In order to use such models as design tools, they shall necessary be, at the same time, highly accurate and computationally efficient. Two different approaches will be followed throughout the project: the first is based on the concept of the pseudo-rigid body, the latter on combinations of rigid and flexible bodies in which pseudo-rigid and flexible elements coexist. When dealing with nonlinear dynamics of reduced-order models, the main challenge is the identification of the parameters and their dependency on operative conditions. This task will be performed through model updating based on optimization techniques in an innovative numerical schema based on fuzzy arithmetic, to assess the uncertainties related to the parameters’ identification and to the simplification of the model itself. Coupled with
the multibody model, an innovative acoustic model will be also proposed, converting the vibration output of the multibody models into an acoustic measure. Finally, the models will be verified against experimental results. Scientific literature lacks a significant body of experimental results to be used as reference, thus an important experimental campaign will be carried out to obtain the necessary reference data, which will be then made available to the public. The outcomes of Hypergears will make it possible to develop a simulation model capable of identifying, and therefore predicting, complex operating phenomena in gears such as transients, gear shifts, non-linear dynamics phenomena, noise, and backlash. At the current state of the art, these phenomena cannot be evaluated within a single simulation environment and are generally unsuitable for design optimization.