Yes, the 3D overlay is the entire point. A heads up display is just looking at the blueprint on a piece of paper with an additional layer of complexity, it wouldn't remove the need to manually measure, nor would it provide any assistance in spotting missing attached pieces (or some extra pieces). Once the model is overlayed QC goes from having to measure the placement of every pieces and the location of every hole to just walking around the finished assembly and ensuring that every conforms to the civil engineer approved model. A half hour process can be done faster and more precisely in 5 minutes, you notices very quickly when there is solid steel where the hologram has a hole, or thin air where the hologram shows that a plate was suppose to be welded on.
replyHave you looked into OpenSplat type of post-processing? You take a bunch of pictures and then let hardware create a 3d model. It's really competent and could easily create a rectified model for measurements. To get actual values, you'd need some control points, but beyond that, a pipeline that continiously creates models could be feasible.
replyThen your QC guys are mostly behind computers and rotated to the floor when things are identified.
Ultimately, your VR isn't doing anything more technically accurate than this.