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Tire model is one of the most significant components of vehicle ride and durability simulation. A balance of calculation accuracy and computational efficiency is always desired in the modeling work. This paper proposes a new discrete ring model for the characterization of the tire enveloping properties. Two modeling concepts are put forward: assuming a stationary tire loaded on a moving road. In this case, the contact interactions can be treated with a tread arc instead of a complete circular. The second operation is decoupling the grid discretization of the tire structure. A higher number of the discrete units at the pre-contact area convinces the calculation results. The discrete elements are relatively sparsely distributed at the non-contact region, which guarantees a competitive time consumption. In this paper, the simulations are validated with the measurements of different operational conditions.

The vehicle handling dynamics stands in the central place of the automotive developing processes. The accurately parameterized vehicle handling models play an important and useful role at different vehicle developing phases. At the early phase of vehicle development, they can be used to set the desired target by comparing the handling characteristics of competitors' vehicles. For the further developments of active systems, the right parameterized models are the basis to design the control systems in a virtual simulative environment. Therefore, there are the strong needs to develop a systematic methodology to parametrize the vehicle handling models, whose qualities should also be assured by the validation of field tests. The kinematics and compliance (KnC) behavior of the suspension is in the focus of this study. Compared with parameterization methods of other chassis subsystems, sensitivity analyses of suspension KnC testing conditions were very few in literatures published.

This paper describes a new hybrid algorithm for multibody dynamics in vehicle system dynamics which combines the advantages of both embedding technique algorithm and augmented formulation algorithm. An approach to vehicle dynamics modeling based on the hybrid algorithm is presented. Embedding technique algorithm has relatively small number of equations of motion. With help of this technique, an enhanced parametric vehicle dynamics model can be built, representing characteristic curves of suspension comprised in kinematic and compliance. Small number of equations enables the vehicle dynamics model to be simulated very efficiently. In comparison to embedding technique algorithm, the main benefit of augmented formulation algorithm is relatively simple for computer programming. With help of augmented formulation algorithm, the structure of the vehicle dynamic model can be easily extended.

The aim of this investigation is the improvement of the lateral vehicle dynamics by optimizing the rim width. For that purpose, the rim width is considered as a development tool and configured with regard to specified targets. Using a specifically developed method of simulation, the influence of the rim width is analysed within different levels - starting at the component level “tyre” and going up to the level of the whole vehicle. With the help of substantial simulations using a nonlinear two-track model, the dimensioning of the rim width is brought to an optimum. Based on both, tyre and vehicle measurements, the theoretical studies can be proved in practice. As a result, the rim width has a strong influence on the behaviour of the tyre as well as on the overall vehicle performance, which emphasises its importance as a potential development tool within the development of a chassis.

In ride comfort as well as driving dynamics, the behavior of the vehicle is affected by several subsystems and their properties. When analyzing the suspension, especially the characteristics of the main spring and damper but also rubber bushings are of main importance. Still, the properties of the different components are dependent on the present operating conditions. Concerning rubber bushings, several effects have already been investigated, e.g. dependencies of the transfer function of frequency, amplitude or load history. In this context influences of changes in temperature are often neglected. However, in the following research, the focus specifically lies on determination and analysis of the temperature dependency of rubber bushings. For this purpose, initially the relationship between properties of pure rubber and rubber bushings is described, which serves as a basis for correlating respective temperature dependencies.

Starting from the USA and followed by the European Union, legal requirements concerning “Tire Pressure Monitoring Systems” (TPMS) for passenger cars and light trucks will be introduced in China as well and therefore in the third of the three largest automobile markets worldwide. Changes of pressure dependent physical tire properties such as dynamic roll radius and a certain tire eigenfrequency, which are included in the ESC-wheel speed signals, indicates pressure loss in an indirect manner. Systems with corresponding working principles are called “indirect Tire Pressure Monitoring System” (iTPMS). Since the tire is a structural element with varying characteristics according to the design parameters, the roll radius and frequency behavior due to pressure loss is variable as well. As a consequence, tires have to be evaluated regarding there compatibility to iTPMS during the vehicle development process.

In investigation and development of road tires within passenger car development, temperature dependency of tire characteristics is often neglected. This research however explicitly focuses on investigation and identification of temperature dependency of tire characteristics and its interaction with other inner tire states. To this extent, a novel method using a thermographic camera for measurement of both tire core and surface temperature is used. On the basis of these measurements, the dependency of cornering stiffness, relaxation length and lateral coefficient of friction on either core or surface temperature is presented. Moreover, the effect of tire core temperature on inner pressure is investigated. By choice of appropriate operating conditions, the effects of temperature and inner pressure on tire characteristics is investigated separately. A mechanical-analytical analysis forms the basis for derivation of the relationship between material attributes and tire characteristics.