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The full vehicle simulation on durability proving grounds is a well established technique in the development process of passenger car manufacturers. The respective road surfaces are designed to generate representative spindle loads and typically include events that will result in large tire deformations. Depending on manufacturer and the combination of vehicle size and wheel properties, these deformations can be so large that the tire belt and/or sidewall have contact with the rim crown (protected by the tire sidewall). The current tendency to low-aspect ratio tires reduces the available deformation capability of the tire while simultaneously introducing larger nonlinearities in the sidewall behavior. After a short overview of the standard modeling technique used by the CDTire model family to handle such events, a refinement of this technique is introduced, modeling both the non-linearity behavior of the sidewall and a possible subsequent rim contact.

The full vehicle simulation on durability proving grounds is a well established technique in the pre-development process of passenger car manufacturers. The respective road surfaces are designed to generate representative spindle loads and typically include events that will result in large tire deformations. Depending on manufacturer and the combination of vehicle size and wheel properties, these deformations can be so large that the tire belt and/or sidewall have contact with the rim crown (protected by the tire sidewall). The current tendency to low-aspect ratio tires reduces the available deformation capability of the tire while simultaneously introducing larger nonlinearities in the sidewall behavior (see [ 2 ]). This paper is based on a co-development project between Fraunhofer LBF and Honda R&D and is dealing with the development of a tire model, which can accurately handle very large deformations of the tire up to misuse-like applications.

Rolling resistance and tread wear of tires do particularly influence the maintenance costs of commercial vehicles. Although tire labeling is established in Europe, it is meanwhile well-known that, due to the respective test procedures, these labels do not hold in realistic application scenarios in the field. This circumstance arises from the development phase of tires, where the respective performance properties are mainly evaluated in tire/wheel standalone scenarios in which the wide range of usage variability of commercial vehicles cannot be considered adequately. Within this article we address a method to predict indicators for rolling resistance and tread wear of tires in realistic application scenarios considering application-based factors of influence like specific customers, operation circumstances, regional dependencies, fleet specific characteristics etc. Moreover, the prescribed methodology may also be transferred to the prediction of fuel consumption and pollutant emission.

In the last two years, Fraunhofer has developed an advanced tire model which is real-time capable. This tire model is designed for ride comfort and durability applications for passenger cars and trucks, as well as for agricultural and construction machines. The model has a flexible belt structure with typically about 150 degrees of freedom and a brush contact formulation. To obtain sufficient computational efficiency and performance for real time, a dedicated numerical implicit time-integration scheme has been developed. Additionally, specific coordinate frames were chosen to efficiently calculate and use the needed Jacobian matrices. Independently from this, Fraunhofer ITWM has developed and installed the new driving simulator RODOS (RObot based Driving and Operation Simulator), which is based on the industrial robot KUKA KR1000.