A key affordance of AR during construction is to provide guidance to builders when fabricating complex geometries. Here is an interesting use case where computer data has been overlaid onto a physical site to help build a complex tile vault which would have proven difficult to construct using traditional means. While the technology utilised does not fall neatly within the 'mobile AR' focus of this research project, the principles remain the same; it is not difficult to see how this same computer data could potentially be viewed through a Head Mounted Display, leaving the builders' hands free for construction.
The authors of the project note that their workflow uses minimal 'physical' guidance, which effectively does away with traditional 2D drawings (ie: plans, sections, elevations) that require further interpretation. Overlaying data from a computer model directly onto a physical site eliminates the need to 'flatten' complex 3D shapes into their 2D representations which, with freeform geometries, can be very difficult to read. Using AR, the workflow moves seamlessly from the '3D' depiction of the virtual computer model, to a 3D overlay of this information in real-time on the construction site. As the builder works to geo-spatially located points from the computer model, the construction process is sped up, and the likelihood of errors reduced.
