# HMD-Based VR Tool for Traffic Psychological Examination: Conceptualization and Design Proposition
## 4 Discussion  
In the present paper we discuss the current body of knowledge about the use of wearable VR technologies for traffic psychological examination (TPE). Since the standard TPE was found to possess several limitations, especially with respect to specific populations or limited ecology [6; 10; 11], new approaches for TPE are suggested. We emphasize the potential of combining cost-effective wearable HMD VR devices with interactive haptic driving interfaces as a promising platform for driving skills assessment, and we perceive situational awareness as a central construct for the TPE. The VR technologies, regarding their recent massive development as well as imminent features of cognitive and physical fidelity, immersiveness and availability, were found to be a viable trend for valid and effective driving assessment [44; 46], which have the potential to surpass expensive high-fidelity driving simulators by mobility, dissemination, minimal maintenance and price. Regarding VR technologies, current as well as potentially desirable measures for driving assessment based on recent advances of low-cost virtual technologies are outlined. Considering the crucial position of situation awareness as a psychological construct significantly predicting driving decision-making and driving behavior, the specific role of eye-tracking technologies embedded into VR is emphasized [50; 68; 69; 70; 71]. Based on the empirical and theoretical summary, the specific HMD-based driving assessment tool is proposed. The potential of currently available technologies for variable measurement is discussed and selected to design a prototype of a mobile cost-effective driving simulator, which can be suitable for a safe driving simulation and follow-up driver assessment out of the research institutions. Further, the basic path diagram of crucial variables potentially affecting situational awareness is proposed as a suggestion for further research on VR driving assessment. The abovementioned combination of VR technologies and eye movements tracking, in comparison to standard TPE, emphasizes the ecology of the driving assessment since it better represents the state of the real world where driving naturally occurs [44]. With the  
Figure 5: Selected technologies for VR-based TPE tool: Thrustmaster T300 RS (**left**); HTC VIVE pro eye (**right**). use of HMD interface, we can precisely and concurrently measure several aspects relating to the driving process in real time, so crucial variables such as SA can be measured. The examination scenario can be dynamically modified based on the real time (inter)actions of the driver or her/his recorded physiological state. The data can be subjected to the automated analyses. The eye-tracking technology can be used to study driving interfaces such as the strategies when reading GPS navigation, checking fellow passengers, conspicuity--i.e., the probability of perceiving an object in the visual field or the distractibility by visual smog. Next to ET technology, since the virtual assessment can be easily kept in the lab, the measuring interface can be complemented with measures such EEG, ECG, GSR or blood pressure measures or, e.g., saliva analysis, etc. [48; 118]. The true strength of complementarity is enhanced by VR technology, where the real-time body feedback from the ecologically valid simulation can be effectively recorded and used for complex assessment of driving skills. The combination of the various cognitive, motoric physiological and emotional aspects measured at the same time may provide a comprehensive perspective on the actual level of the driver skills. The next step of the research will be constructing the proposed HMD-based driving platform with the functional driving scenario. Using this platform, the empirical measures are about to be done to test the used HW setting and validate the proposed SEM path diagram. The further direction is creating norms in the driver performance on the HMD-based tool, further optimization and potential dissemination into TPE practice.