Subjective evaluation of high-fidelity virtual environments for driving simulations

Virtual environments grant the ability to experience real-world scenarios, such as driving, in a virtual, safe and reproducible context. However, in order to achieve their full potential the fidelity of the virtual environment must provide confidence that it replicates the perception of the real-world experience. The computational cost of simulating real world visuals accurately means that compromises to the fidelity of the visuals must be made. In this work a subjective evaluation of driving in a virtual environment at different quality settings is presented. Participants (n = 44) were driven around in the real world and in a purposely built representative virtual environment and the fidelity of the graphics and overall experience at low, medium and high visual settings were analysed. Low quality corresponds to the illumination in many current traditional simulators, medium to a higher quality using accurate shadows and reflections and high to the quality experienced in modern movies and simulations that require hours of computation. Results demonstrate that graphics quality affects the perceived fidelity of the visuals and the overall experience. When judging the overall experience, participants could tell the difference between the lower quality graphics and the rest but did not significantly discriminate between the medium and higher graphical settings. This indicates that future driving simulators should improve the quality, but once the equivalent of the presented medium quality is reached, they may not need to do so significantly