Immersive virtual spacewalking in stakeholder workshops:the effect of immersive, BIM-driven design and interaction tools on human sense of presence

IntroductionOver the last decade, the use of Building Information Modelling (BIM) has become increasingly wide-spread to manage the growing complexity of construction projects. As a result, project managers are facing new challenges in managing stakeholders in BIM projects, as the BIM concept is still relatively new to many of the stakeholders (Leśniak, Górka &amp; Skrzypczak, 2021). The introduction of BIM has brought new and complex activities into the already complex process of project management, resulting in a radical change in the working practices of project managers and in the working practices of the project stakeholders (Li et al., 2021). Besides the purely technical advantages of better(?) planning and manipulating data, plans, etc. used to get the best possible visualization of the future, human factors are at least as, if not more, important when looking into the future. Immersive virtual reality (VR) can transform virtual plans into a walkable world, so that different stakeholders (architect, builder, tenant, etc.) can walk through the same flat without the need for specialist expertise in understanding building plans (Schiavi et al. 2022). This same mental picture of the e. g. apartment can now have an impact on decision-making processes and shorten the time to final judgement. At the same time, different aspects of interior design can be explored (size effect, furnishing, etc.). In our mixed methods study, we wanted to know which interaction mechanisms play an important role in the immersive virtual world and whether the sense of presence (illusion of place) is changed by the virtual design of rooms. MethodsIn three workshops, planned BIM data of two different types of apartments were put into a virtual environment (UNITY3D). We optimized the virtual apartments for an immersive virtual reality walkthrough and developed interactive tools for exploring the virtual apartments. In the first workshop (W1) we aimed to assess and demonstrate the sense of space of the planned apartment. In the second workshop (W2) we focussed on the texturing and in the third workshop we demonstrate the kitchen &amp; wet room variants. Form W1 to W3 the visual details and naturalistic implementation of the virtual apartment were gradually enhanced. The participants were tenants, building owners, architects, and employees from the local building office. Their experience in virtual reality varied from none to a lot of experience. There were different tasks and goals for each workshop. Beside discussions, there was at least one VR-experience session per workshop, where participants would experience the virtual room in groups of two, with tasks specific to the session. This was done with three HTC VIVE pro headsets (one per group) with one per-son experiencing in the virtual world and the other spectating the first-person view from on a 75” screen. After some time, they swapped medium and the person who was in the virtual world now watched from outside. We recorded the following data during the workshop: technical affinity with TA-EG (Karrer, Glaser, Clemens &amp; Bruder, 2009), usability with UEQ-S (Schrepp, Hinderks, Thomaschewski, 2017) and sense of presence with PLBMR (Frank &amp; Kluge, 2014). Additionally, the participants were interviewed several weeks after the workshops with half structured interviews: Over all workshops a dataset of N=13 participants could be archived and evaluated. Descriptive and non-parametric statistics were calculated with SPSS 21. The coding of the interviews was done with MAXQDA.ResultsWe found a heterogeneous group in the scales for technical affinity. Regarding the importance of the tools we found that not all tools were remembered in the interviews. The overall usability rating was good and the most important finding was a significant less sense of presence (PLBMR) in workshop 2 (p &gt; .05, cohens d`=.21).DiscussionThe introduction of BIM resulted in a radical change in the working practices of project managers and in the working practices of the project stakeholders (Li et al., 2021). This change should be carried out in a way that most stakeholders should feel comfortable with. As we saw in the data, the usability ratings were good, but some interviews showed that a reduction in complexity may be a further improvement, since not every feature was remembered or needed in the virtual room (Schiavi et al. 2022). The decrease in sense of presence in the second workshop show a possible connection with the uncanny valley phenomenon. Also, the limitation of the study is discussed and an outlook of possible further research is suggested.