The chassis as a data source for the digital twin of the road system

The "Digital Twin of the Road System" is intended to lay the foundations for analysing and controlling the road of the future as an intelligent system that will subsequently enable efficient use of the road infrastructure while meeting the requirements of future mobility. As the main user of the road system, the vehicle plays a central role in the development of the digital twin. Interaction between the road and the vehicle takes place via the chassis subsystem, including the tires. The contact area between the tires and the road is used for power transfer, which is relevant for the vehicle dynamics on the one hand and contains detailed information about the road surface on the other hand.

The aim of the subproject is to develop a concept for determining this information in order to provide the Digital Twin of the Road System with real-time data on the dynamic loads applied by the vehicle and the road condition. The use of real load data enables the derivation of measures for a more rational use of the road infrastructure by vehicles. In addition to its primary purpose as input data for the digital twin, the data collected is also highly relevant for the development of future active chassis systems to improve vehicle safety.

As the first component in the load path between the road and the vehicle, the tire plays a central role in this subproject. However, real-time data on the interaction between tire and road cannot be collected directly, as a direct measurement of the force distribution in the contact patch is not possible. To meet this challenge, a model-based approach for data generation is chosen. At the core of this approach are real-time capable vehicle and tire models whose input data are provided by a distributed sensor network concepts in the chassis. The sensor network concepts consist of combinations of sensors, which are already present in modern vehicles, such as acceleration sensors, and novel sensors with scalable potential. These are systematically analysed and evaluated. The most target-oriented concept will be prototypically implemented. In order to collect the data set for the development of the software for the individual sensor modules, variety of tire and vehicle measurements will be carried out under a wide range of operating conditions. To isolate the influence of the chassis transfer behaviour on the tire response, measurements on sub-system level in a laboratory environment will be conducted. These influences will be further investigated, by the means of system level measurements with a test vehicle, considering a wide range of vehicle manoeuvres. Data fusion between the model-based sensor concept and the sensor network concepts ensures the provision of accurate dynamic wheel load data in longitudinal, lateral and vertical directions as well as data on the actual road surface condition in real time.