OK. Well. I carried out my first survey with Structure on Tuesday. It was a listed building and very quirky with odd split levels etc.
First Survey, so I wasn’t going all out to just use Structure as I am aware of its accuracy ‘limitations’ so I was using my usual Leica Disto and companion Sketch app to do my usual measure up and record.
I recorded all the major rooms with Structure (and Disto) as well as complicated areas where the scan was going to capture way more info than was going to so I could refer back to it later if reqd. (on a side note, the wide angle lens you get with the kit is an absolute godsend for taking photos in tight spaces;0)
So nearly did the whole thing on the first day (took a while as I was doing both) but had no problems with the capture software, just took a few goes to get the knack of doing a room - drawing curtains, avoiding mirrors, identifying a signature bit of furniture that you can use as reference.
Basically the Structure sensor is aligned with the iPad camera and a wide angle lens, so it captures through the IR lasers for depth and the RGB from the iPad camera. But. as you make a circuit the system can acquire drift, as you get back to a starting point, the system can recognise this and an ‘Enhance’ button appears which corrects for this drift - it works best if there is furniture and other items in the room that act as a signature that the system recognises a prior point but it doesn’t always work. But you can do as many scans as you like until you get one you are happy with.
So by the end of the first day I had done all of the internal rooms bar one and the exterior, so I arranged to revisit the next day to complete the survey. On my return did some standard measurements on the rear exterior and started on the last room. Now, Ive been using my Leica Disto and companion Sketch app for a couple years and recognise that the Sketch app is flaky at best and seems to get slightly more flaky with each iteration but when I got it there really wasn’t much if any competition available at a reasonable price so I stuck with it and its general crapness. Anyway while I was doing the last room, it started to get slow and not record gestures or input so I jumped out of the app, killed it and reopened it as per usual to give it a fresh start. Yep, lost everything from the previous days survey, kind of angry but the client was in the room so couldn’t swear too much.
Obviously I still had all the scans in Canvas so I had to go back through the house and do another measurement survey, in which, I didn’t record nearly as much as I did the previous day. I scanned pretty much everything and just took critical dimensions with my Disto.
Anyway, I UL’ the major rooms to the Scan to CAD service and I got back my first set of rooms this evening in .Skp format. I was a little apprehensive given I hadn’t used it before and I’d invested in the hardware etc but hey, its great to be pleasantly surprised and I was! the files came back nice and clean, layered (I need to re-layer them to fit my workflow) and the accuracy is definitely good enough as the rooms were represented correctly and I can adjust to fit my critical dimensions.
On the accuracy point, I went into this knowing what the score was, so If you are doing a room, the further away you are from the target, the lower the accuracy. From my initial checks this eve my accuracy ranged from with 10mm to around 50mm, this is inevitable as sometimes you just cant get close enough due to furniture items etc, Occipital say that you can expect an accuracy of about 0.14% at 400mm and 0.3% at 1m, my first time sort of bore this out (ish), if I was thinking about how I was scanning rather than just waving the thing about, I got much better results - bizarrely the accuracy is higher at the periphery rather than the centre of the scan, I’d love to know the technical reason behind this.
So as an initial gut feel I am very happy with the kit and the result as I have a bunch of rooms done that I can stick together in SU and use a base for the remainder of the model - it has saved me a TON of time as getting a detailed model up to scratch takes (me) a great deal of time and I can concentrate on the remodel design. (fun bit)
When I’ve got my other scans done and done more work in SU I’ll give a more detailed response.
Just as an aside - the Canvas app captures everything so its another source of survey data as well as measurement, photos, panoramas, video etc. It grabs 100% which you can go back into later and take a measurement within the app, so If you forget to take particular measurements (which happens to me all the time) - you can get a steer from the scan even if you haven’t had it converted to an .skp
So to wrap up. Pretty fantastic, sits in my workflow well, accuracy is definitely ‘good enough’ alongside other survey data , I just need more practice. Oh, the client thought it was amazing - she even got me to scan her dog!