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Gearbox behavior is strictly affected by gears, shaft, bearings and casing stiffnesses. As a matter of fact, their contribution to gear dynamics is fundamental for mechanical transmissions design. In this paper a semi-analytical model developed for the estimation of the dynamic behavior of two mating gears is presented and tested on two case studies. Starting with the estimation of the Static Transmission Error, intended as the difference between the theoretical and actual angular position between the two mating gears, the dynamic behavior of the mating elements is estimated by means of a Dynamic Model. The Dynamic Model takes into account the gears, the contact between teeth exchanging loads and the other mechanical elements reduced by means of a DOF reduction technique. Based on the block-oriented approach, Dynamic Model allows the user to easily manage the complexity of the system with further or less elements by adding or removing DOFs.

The paper presents experimental investigation and numerical simulation of a commercial exhaust manifold gasket. Non-linearities in geometric and material behavior make exhaust manifold gasket modeling quite complicated. In the paper, two different FE modeling techniques are compared in order to suggest the best modeling way. Experimental data are collected in order to validate the numerical models. Differences between the two modeling techniques are emphasized and a choice criterion is suggested.

The complexity of automotive market, the request of new gearbox layout able to improve the efficiency of a vehicle and the requirement of quick and effective design of gearboxes push the designers to seek new technologies, new layouts, new solutions. The typical development of a gearbox requires a lot of time and engineers' effort and it often implies a lot of time to define the right layout. The idea of developing a "paradigm" able to guide the designer through the design process seems to be effective. Starting from the experience of a code called "Engine Paradigm" where such idea was firstly implemented, the authors propose in the present paper the development of a code able to suggest a first attempt design of a gearbox. The "Gearbox Paradigm" code requires few data introduction, as torque, power, number of gears, some geometrical constraints such as the axes gap the gearbox layout, and the code elaborates a proposal of CAD design of a gearbox.

The aim of this paper is to study in deep the peculiar test-rigs and experimental procedures adopted to the fulfilment of the principal requirements of automotive steel wheels, in particular regarding fatigue damaging. In the discussion, the standard requirements, the OEM specifications and the dimensional and geometric tolerances are approached. As result of an increasingly necessity to improve the performance of the components, innovative virtual test benches are presented. Differently from their traditional precursors, virtual test-rigs give an extended view of the physical behaviour of the component as the possibility to monitor stress-strain distribution in deep. In the first section, the state of the art and the specifications are listed. Secondly, the adopted hardware test-rigs as the experimental tests are described in detail. In the third one, proposed virtual test-rig is discussed.

In this paper a test bench for measuring the Static Transmission Error of two mating gears is presented and a comparison with the results obtained with the commercial software GeDy TrAss is shown. Static Transmission Error is considered as the main source of overloads and Noise, Vibration and Harshness issues in mechanical transmissions. It is defined as the difference between the theoretical angular position of two gears under load in quasi-static conditions and the real one. This parameter strictly depends on the applied torque and the tooth macro and micro-geometry. The test bench illustrated in this work is designed to evaluate the actual Static Transmission Error of two gears under load in quasi-static conditions. In particular, this testbed can be divided in two macro elements: the first one is the mechanism composed by weights and pulleys that generates a driving and a braking torque up to 500 Nm.