Road Test Emulation: A Data-Driven Calibration Approach

The resource-intensive process of road testing constitutes an essential part of the development of powertrain software. A significant proportion of explorative tests and adjustments for use in service are conducted during the vehicle test phase. However, the observed trends of decreasing development cycles and increasing system complexity generate a field of conflicts. In order to address this issue, this paper proposes road test emulation as a data-driven approach for continuously adapting powertrain software to the evolving overall system. A dedicated data strategy is designed to enhance customer-oriented software development. Therefore, test scenarios equivalent to in-service conditions are determined based on customer data. These test scenarios enable an emulation of road testing and the analysis of the system in a real-world operational context from the early stages of the product development process. System-specific data from the vehicle under development itself is utilised to define the initial parameter settings of the software. A generic approach to system-specific and customer-oriented calibration is presented. The example used is that of the causal, rule-based energy management of a performance-hybrid vehicle. This process results in the definition of an efficiency- and comfort-driven parameter set for the electric drive control, which is compared to a reference in various test scenarios. The method presented enables the data-driven generation of customer-oriented parameter sets and the quantification of the effects of comfort adjustments on the efficiency of the system in real-world operational contexts. Utilising software-in-the-loop simulations enables continuous implementation and iterative adjustments of the parameter sets and powertrain software throughout the product development process. The early consideration of in-service operations facilitates a shift-left in development activities. This supports an enhancement in the level of maturity at the beginning of road testing for the purposes of final calibration and testing of extreme conditions in the vehicle.