Structured Eyetracking-based Requirements Validation with the Help of Virtual Prototypes

Customer requirements form the basis of every product development project. Incomplete requirements and lack of involvement of customers are the main factors for the failure of a product at the buyer's market (Hull et al. 2011). The Quality Function Deployment (QFD) describes a common method for translating customer requirements into product features. For this purpose, the QFD provides various matrices for the prioritization and quantification of the requirements, through the various phases of the product development. The first customer tests are carried out with physical prototypes in the later phases of the PEP. These allow the validation of the customer requirements and the verification of the fulfillment of the customer requirements by the product characteristics (Rupp 2014). This occurs at a time when the influence on the product to be developed becomes smaller. Virtual product presentations provide an opportunity to simulate the first findings about the product characteristics and functions early in the product development process. Due to the functional support, the virtual prototypes allow a real-time interaction by the test persons. Thus, it becomes possible that digital images of products can be interactively experienced. Operating units of technical devices and their operating concepts can be analyzed early on their intuitive use. Product features of virtual prototypes can be analyzed in a highly immersive stereoscopic virtual space. The generated virtual prototypes could query the actual areas of interest of the customer in connection with an eye-tracking system.It is unclear whether the various visual perceptions of the prototypes differ between the virtual and the real world and thus unsatisfactory validation results can occur. A study already planned by the department will reveal possible differences in perceptions. Two-dimensional (2D) monocular eye trackers already allow to analyze the focus of attention and the perception of the customer (Duchowski 2007). By measuring the fixation points (particular sighted point in space), fixation duration, saccade (short jumps from one fixation to the next) and the fixation order, conclusions about the attentional processes of the subjects can be drawn (Rey, 2015). In the three-dimensional simulation, the estimation of binocular eye-tracker still poses major challenges, as with the third dimension the stimulus now will be extended to another level, the depth. In this context, it should be discussed whether the perception of virtual prototypes can be equated with physical prototypes. The necessity and characteristics of a comparative study to investigate the perceptions of both 3D VR and the reality is derived and described. The test objectives and test design are explained.