Schlüsselwort: Gefallensurteil

Motor vehicles embody a successful symbiosis between technology and design. The design of a vehicle is defined by numerous functional relationships. As an example consider the drive unit having an immediate effect on a vehicle‟s exterior body. External constraints like technological advances, shifting social standards and economical enforcements lead to changes within the design process and affect the exterior body of future vehicles. One main aspect of this research study discusses the issue, how the vehicle exterior design is influenced by technical features. From a customer‟s point of view the design of a vehicle is a very important product characteristic. Hence, it is important to be aware of the influence of the parameters of the vehicle design and their impact on the viewer‟s judgement. This thesis considers the influence of technical aspects on future vehicles‟ exterior bodies. It has been analysed which kinds of vehicle designs, especially which exterior bodies, are relevant for future cars and how the exterior bodies of these vehicle concepts are perceived by the viewers. To answer these questions a methodical approach is developed, in order to predict future vehicle exterior bodies. Afterwards the effect of the detected vehicle concepts on these viewers was examined in a survey supported by computer-aided vehicle illustrations. Chapter 2 contains the theoretical basis and defines fundamental terms of the study. Subsequently, the vehicle exterior body is defined for further analysis and for the following modelling process. The vehicle comprises a front section with front overhang and a rear section with rear overhang. The central compartment belongs to both sections. On that basis more detailed body areas can be defined. The theoretical discussion focuses on the fields of product design (chapter 2.1), visual perception (chapter 2.2), aesthetics (chapter 2.3) and future vehicle concepts (chapter 2.4). In this context scientific studies related to the design review of vehicles are analysed (chapter 2.5). To specify relevant exterior bodies for future vehicles, a methodical approach is proposed in chapter 3. The foundation of this approach is the definition of the exterior utilizing the attributes layout, shape, colour with surface and graphics [MAIER ET AL. 2016]. Based on customer requirements [BRAESS ET AL. 2013A, S. 12] and alteration impulses [PREUSCHOFF 2010, S. 26 f.] the method deduces connections between technics and design. Essential tools of the approach are matrices which correlate and combine all important aspects of the relevant issues. Initially the procedure points out important technical influences by, e. g. battery compartment, aerodynamics, reduced parking space, etc. All these lead to specifications related to the dimensions of future vehicle exterior bodies (chapter 3.3). After the analysis of feasible vehicle exterior bodies front and rear design types additive (A), cubic (C) and integral (I) are defined. The combined exterior body types were correlated with the specifications above. The final result is a method for predicting vehicle exterior bodies of future vehicles (chapter 3.6). Using this method it is now possible to extract a portfolio of various future vehicle concepts including explicit dimensional specifications (chapter 3.7). Based on this theoretical prediction adaptive 3D-CAD vehicle models were developed (chapter 4). With these stimulus patterns of vehicle illustrations were created. To reach an appropriate level of abstraction, specifications for modelling and pattern generation were defined. Finally 36 models and stimulus patterns were generated for the survey with subjects. These vehicle models were designed with different types of vehicle exterior bodies to represent the complete vehicle concepts portfolio of the previous prediction. In preparation for the survey the test layout and setting were designed and optimized with a pretest (chapter 5). With the results of this pretest CAD-models and stimulus patterns were revised. Within the main survey 36 stimulus patterns were shown to 80 subjects. Six patterns were shown twice as a repeat measurement. The subjects had the task, to assess the appeal of the shown vehicle representations on a seven stage rating scale. During this process the eyes of the subjects were tracked by a remote eye tracker. The evaluation of all test data is described in chapter 6. The values of appeal were visualized with boxplots and analysed with inferential statistical methods (chapter 6.2). The results indicate that modifications of the vehicle exterior body do affect the appeal of a vehicle. The gaze data was analysed with heat maps and areas of interest, called AOIster 6.3). One stimulus pattern included vehicle representations in three different points of view: side, oblique rear and oblique front. The evaluation of view-based AOIs showed that all views were used by the subjects. Furthermore, it appears that there are important parts of a vehicle‟s exterior body, on which the subjects focused independent of the type of exterior body. The evaluation time, analysed in chapter 6.3.4, was found to depend on the appeal level. Strong likes or dislikes led to shorter evaluation times. Finally, the results are interpreted in chapter 7 and related with the outcome of the prognostic method in chapter 3, so that a visualisation within the implemented parking illustration is possible. In this respect critically and mainly positively valued modifications of the vehicle dimensions were also analysed. Very slim vehicles, e.g., are in general assessed negatively throughout all types of exterior bodies. Additionally, the study shows that the appeal of the vehicle illustration with dimensional changes also depends on the type of vehicle exterior body. Within this study the four methodical steps were developed. In summary, it was researched which vehicle exterior bodies received positive values by the subjects. In combination with the prognostic data functional and formal potentials of the analysed vehicle concepts were specified. This study focused on the vehicle exterior body. With the knowledge of valuation and perception of the vehicle exterior body it was elaborated how the vehicle shape could be specifically designed to vanquish the detected problems. The current research study underpins the scientific potential of the interdisciplinary topic of automotive engineering and design. Therefore, functional aspects of vehicle development and formal aspects of design theory were linked by a user-centred approach. Thus it was possible to measure the appeal and perception of vehicles‟ exterior bodies with different kinds of exterior bodies and dimensions. The practical application of these findings is well suited for the early stage of vehicle development, before position and arrangement of the modules are specified. The results of the study also point the way to further research topics in the context of automotive technique and design according to other design properties, e. g. shape, colour with surface, or graphics. Moreover, promising scientific overlaps with other fields of automotive engineering are to be expected, such as car body technology, aerodynamics and interior spatial effects.