Subjective Perception Prognosis of Divergent Data Sets of the Shift Strategy of Modern Dual-Clutch Transmissions on the Basis of Simulation Results
Authors:   Karlsruhe Institute of Technology (KIT), IPEK - Institute of Product Engineering, GERMANY, Köber John , Albers Albert ,   Karlsruhe Institute of Technology (KIT), IPEK - Institute of Product Engineering, GERMANY, Jacobs Paula Marta ,   TU Braunschweig, GERMANY, Karakus Ercan ,   Hochschule Albstadt-Sigmaringen, GERMANY
Published: March 2022

The objectification of customer, user and supplier requirements in the development process is an important task to translate abstract requirements into the language of the product developers. However, this is particularly challenging in complex contexts, such as the adjustment of shift points of a transmission, since this system has a very strong interaction with the overall system. The subjective adjustment currently takes place very late in the development process, in the so-called hardware phase of the overall vehicle integration. However, the adjustment and definition of the shift points of modern dual clutch transmissions is a fundamental part of today's vehicle developments. In particular, the subjective perception of the application engineers in the context of so-called driveability is decisive for the milestone release of data statuses in the automotive product development process. Currently, a large part of the application process, including the associated validation, is thus based on global test drives with physical prototype vehicles. Due to the necessity of prototype vehicles, this process can only take place at a correspondingly late stage in the product development process. This results in a rigid application and validation process that is very closely timed. If subsequent changes to the data status are necessary after the very time-consuming and cost-intensive process, it is hardly possible to validate the resulting adjustments to the overall customer perception of the product. Thus, it can happen that vehicles are introduced to the market without final validation of the subjective drivability, or a cost-intensive postponement of this must be effected. Simulation models can be used to meet this discrepancy between the time requirements and the desire for sufficient validation. On the basis of this motivation, this thesis deals with the question of how the subjective perception of drivability as a dependency of diverging application data of dual clutch transmissions can be predicted on the basis of simulation results. First, possible influencing factors are identified which have the greatest influence on subjective perception in the context of the shift strategy. On the basis of a selected series data set, it is shown how it can be specifically adapted to achieve a sportier or more comfortable driving style depending on the factors identified. In order to measure the real influence on subjective perception, a test person study was then carried out, whereby the deviations of the adjusted data set from the series data set were always to be evaluated. In order to be able to use directly comparable results for the correlation analysis, the diverging data sets are simulated and evaluated with regard to their expected deviations from the series data set. Based on the simulation results and the statistical analysis of the test person study, a model is then developed to correlate time-dependent simulation data with subjective assessments of diverging data sets. This approach enables a prognosis to be made regarding the subjective perception of drivability. Finally, a method for validation is presented, how this approach can be transferred to another vehicle segment with an alternative automatic transmission concept.