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Claes Lundstrom

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    www.touchcad.com , www.lundstromdesign.com
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  1. Accuracy is, according to their web site, +- 0.5% on a 12 ft long line, so +- 18.3 mm. So, in my experience it does not seem better than the lidar apps I have used for the iPhone 12/13 Pro. Seems rather expensive relative to what it does.
  2. I agree that it would be very useful to be able to control the number of points (beyond high, medium and low), and exact behaviour of a given curve. In my main 3D modelling program, I can set it locally for each given element, part of an element, and numerically to whatever I find relevant for any given task. I find it extremely useful, and could probably not live without it for my type of work.
  3. Have done a lot of such work. The problem is often in the other end, that is, many of the programs used for controlling CNC machines have severe limitations. The software is often simplistic and often ageing. I therefore suggest keeping geometries on a very basic level. In 2D, it typically means using lines, polygons, and arcs to define things. Avoid Berzier and spline curves. Avoid symbols and groups. Avoid using filled surfaces, and for example using Clip Surface to define a hole in a closed polygon/polyline shape. On polylines, only define shapes using straight lines and arcs.
  4. I think the liar is the same on iPhone 12, 13 Pro and iPad Pro. It's basically a matter of taste using a smaller or bigger screen vs how easy it is the bring it along at any give time. A smaller screen works fine for me tough. I have the bigger iPhone 13 Pro model.
  5. There are many apps on Appstore doing this. I checked five or six and decided on Scaniverse as my personal favourite. It's also free, believe it or not. Is it difficult to use? I bet you will get something reasonable good out of it in your first try. It's fairly similar to creating a movie. You get white and red stripes where it still misses data. Just move around with gentle movements and watch was happens on the screen. You need to practice a few times to know how to get the best result, but it's fun and easy. Skinning the model takes a few seconds, in any event less than a minute, after which you can look at the result on the screen in full 3D, including spinning and zooming. You can trim and rotate the model in the app, and even generate a movie or a still shot from any view. Then save the model if the preferred format. I have a Mac, so a quick Airdrop from the iPhone or iPad is the quickest way to export to the Mac. Takes seconds. OBJ gives the best rendering, whereas PLY works best for Digital terrain models. The Ply importer allows you to define the number of points to be used with a slider. Lower res may be good enough. It's a bit like using a well used piece of soap instead of a new one having sharp edges, or using a more or less blurry image to represent the shape. In VW, you import OBJ as OBJ and PLY files as a Point cloud. The sample model contained 469204 points.
  6. Though I would try the other formats supported by the iPhone scanner program. Besides OBJ, it also supports PLY and FBX. Not sure about FBX by this is what came out of the PLY version, when converted into a Digital Terrain model. The model was about 7 megs. The input as such was not as pretty as the OBJ, but the DTM thing working is a plus. Of course, it freaked out a little by the house and resting walls and where there was a steep rock wall, but not bad. Measurements seems t be right too. It only took a few minutes to get to this, plus the five to ten minutes it took to scan the site. Not bad for a phone? I even managed to include my feet here and there by scanning myself.
  7. The scan was more like 10 minutes. You don't get mm precision, for the most part more like within say 10 cm. Heights seems to be more accurate for some reason. To check I measured a seven story stair, and compared it to the real heights and the heights where off by something like 2-3 cm, so the fluctuation was not clearly distinguishable from fluctuations of the eighty year old concrete house. At the most heights where possibly short by say 2 cm on a 2.7 meters height of each floor. The scan was essentially done by walking from the top downwards in the stair, at say half the speed I normally use, while gently moving the camera back and forth. Time, say five minutes at the most. The picture shows a hybrid of scan and measurements. The back side drifted a little in shape due to bad access to a corner. When scanning large objects, it's important to do it using slow and gentle movements. Limitations. The lidar can only measure up to about five meters, so tall buildings are impossible without a drone. Size, just to mess with it, I had a walk around a small local lake, having a circumference of about two kilometers, As you can see from the second picture, it started to get lost about half way around it, but when I made a copy of the cans and rotated it around the point where it got lost, the second part actually worked fine. I placed it on top of a satellite map and the result was surprisingly good, considering that it's not really a measuring device, it's a PHONE. I checked regularly against the water surface to see if it drifted in height, and it basically didn't. It also freaked out completely at about 1.7 of the 2 kilometers, though the data wasn't lost. It just slowed down to a crawl.
  8. I used the this manual method as VW does not seem to like meshes having a couple of hundred thousand triangles. As I mentioned, I generated a flat rectangular 3D polygon and used that as a working plane. The trace takes place that the intersection between the flat plane and the 3D model, a bit like something sticking up on a water surface. I started at the lower corner of the house with Z = 0. I then went to the top (not top plan) and traced the contour around the intersection between the flat plane and the 3D model using OpenGL rendering (or whatever it's called now). I used 3D polygons but it can just as well be 3D loci. Also important to do the tracing in a different layer with no intermediate snapping going on, as VW then freaks out completely. Once one level is done, you simply move the flat plane up some distance, in my case I used 0.5 meters, and traced it again. Remember to move the working plane to the new level. Etc. The result was indeed a site model. Details such as trees are easy to insert when required.
  9. My comment was perhaps not intended to be all that seriously for city planning 😉 The iPhone can be surprisingly useful for smaller projects. The movie was just for fun and was actually created by the iPhone program itself. The purpose of this scan was to analyse a drainage problem on a 30 x 15 meter area. The scan took say 5-10 minutes as the site was rather steep and slippery. The model imported fine into VW though I hade to fit the YZ from this particular program. Converting the model to a DTM seemed to take forever, so instead I placed a plane at a given height and traced the intersections manually in a separate layer not using snapping. I then moved the plane a given distance and repeated the procedure until I got a series of 3D polygons, which was used for creating the DTM. I also did an illustration of the shape using a series of vertical grid surfaces to visualise the shape to the non technical people.
  10. ... or you can use a poor man's drone, an iPhone 13 Pro 🙂 and Scaiverse Poor Mans Drone.mp4
  11. Using lofting of cross sections can be a nightmare in most NURBS based programs, and VW simply doesn't handle NURBS editing very well either, compared to most standard 3D CAD programs. No disrespect intended. VW's inability to nudge control points, and why you can't edit any number of control points in any number of objects at the same time remains a mystery. In my professional boat design program, I can easily tweak 500-1000 NURBS objects at the same time using a random selection of control points, and get an instant update of the lines drawing at the same time. Given the use of VW, you my consider using the following method: 1/ Generate some curves along the length of the boat, say three. 2/ Loft them into a a surface. Convert it into an interpolated surface having four by four controls in the grid (or thereabout) . 3/ Adjust the shape so that it looks reasonable. 4/ Add sectioning to see what the shape looks like. 5/ Repeat step 4 & 5 until the sections get close to the original cross sections 6/ Extract the cross sections to generate the updated buck shape cross sections.
  12. The three point arc mode in the Reshape tool creates arcs like in the picture, where I exaggerated the shape to illustrate it. In reality you need to fine tune it more. This typically works best of the arcs as they are seen as just arcs by many cutter being next to one another The Blue circle is just one object being on top of another, which works better that the second option, where there is a physical hole in the rectangle. You can however achieve this by exploding the model before exporting to the cutter. The fist option is what I typically use within VW as its much more logical.
  13. I have for sure tested it indoors too, and even though it wobbles a bit and generates rounded corners etc, I'm still amazed when I scan from room to room. You need to wing it a bit and double-check key measurements, but the voids generated by walls are clearly there and they are reasonably correct.
  14. Nobody expects it to be as good as the pro equipment, but for smaller projects it may very well be fairly usable, and for getting rough estimates. It was however way better than I expected. And having it in your pocket at all times is great, and its quick.
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