Haptic feedback is more important than VR experience for the user experience assessment of in-car human machine interfaces

Abstract

The user experience (UX) of a product is important for a customer’s decision, especially in the automotive sector. In recent years, a frontloading of UX assessments from physical prototypes to virtual prototypes has occurred. Nevertheless, there are clear indications that established UX assessments methods cannot simply be transferred 1-to-1 from real to virtual evaluation setups as results get biased. For the UX assessment of an in-car human machine interface (HMI) the haptic properties of the knobs and buttons are just as important as their visual features. Therefore, it is mandatory to also simulate the haptic behavior of the in-car HMI in virtual reality (VR) assessment scenarios. However, accurately simulating this haptic behavior adds considerable costs and effort, diminishing the beneficial effects of VR UX assessments. Due to confidentiality reasons the volunteering participants of VR UX studies in the automotive sectors are typically employees with a varying degrees of VR experience. It is unknown if this gap in VR experience biases the results of UX assessments in VR. This paper presents a UX assessment study of an in-car HMI in VR in comparison to reality. From a practitioners viewpoint two research question are investigated: (1) How much is the UX assessment impaired by missing haptic simulation? (2) Does VR experience influence UX assessment ratings in VR? The results show that missing haptic feedback severely diminishes UX ratings, leaving no doubt that meaningful UX assessments in VR can only be performed when haptic is included. This means that more effort has to be put into earlier VR assessments severely reducing its benefits compared to UX assessments with physical prototypes. However, the VR experience of the participants only has a slight effect on the UX assessment results.