Open Source 3d Scanning Software | 3d Scanning For Free

Holocreators GmbH

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3d Scanning For Free

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Hi, my name is Swann with the 3D scanning company Holocreator’s. Today I will show you how to do a 3D scan for free using just your cell phone camera. The technology is called photogrammetry. It has been covered by many video tutorials, But I think whether you are a novice or an experienced user, I will show you something new today because I am not only making the 3D scan for free. I will also make the 3D scan with a professional scanner, which costs around 20,000 Euros and later on I will compare the two. And just a little heads up The deviation between the two is just 02mm. So what we get for free is actually pretty damn good. To follow this tutorial, you will need—well apart from a cell phone camera—four free software packages. You will need Meshroom. That’’s for converting the pictures You have taken into a 3D model. We will need MeshLab. That’s for 3D scan, cleanup and alignment of the different 3D scans. Then you will need Netfabb That’s for taking measurements on the file. And then finally we will need GOM Inspect. This is for comparing the free scan with the professional scan. So the very first step is to actually make a manual measurement. So, for that, I will take this caliper here and I will take a measurement on the flange. If you don’’t have a caliper, you might as well take a ruler. Then I will take 3 separate measurements. That is just to get an average. And then you will see that the measurement is 76.2 mm. And this is our reference measurement, which will get very important down the road. Now we start the actual scan. I will place the part on this yellow box, and then I’’m taking my cell phone camera and I’’m moving around the box, taking many pictures from different angles and perspectives. While making these pictures, I pay attention to have a very good lighting. Actually, the more light the better. But you don’’t want to have harsh shadows on the object. I will make two picture sets of around 100 pictures each. One is where the part is sitting on the flange and one where it’’s upside down. That is because I also want to record the inside geometry of this part. Now, it’’s time for Meshroom. We import the pictures that we just made with camera. That’’s super easy! Just by dragging and dropping. And then you see the start button, You hit that, And the software will calculate the 3D models from this picture. We do this two times. Once from the picture set that we made from the part sitting on the flange and once where it’’s upside down. So in the end, we have two 3D models created. The two 3D scans, which I have created in Meshroo’m. I will now import one by one into MeshLab and here I will remove everything that is not really needed in the scan. Because Meshroom has well apart from the part, it has also recorded some parts of the box and these areas we want to remove. To remove areas of the 3D scan. I can click up here on the button select faces in a rectangular region. And now I have this red selection box and I select it in red, and then I hit the delete key and this is how I can remove geometry. And when I am happy with the result, I can just export it as an STL file. I think I’ve said it before. Photogrammetry is a great technology, but one major disadvantage is that it’’s not according to scaling. Because you have a picture set and the computer calculates a 3D model from it, but it doesn’’t know how big the part is in reality. For that, we now check the scaling of the 3D scan. I will import the 3D scan to NetFabb and here I make a new measurement and then I select 3 points on the outside of the flange and then Netfabb supplies me with the correct measurement, which in this case is 698mm. And now I click on scale. We make a quick calculation. You remember the reference measurement that we have taken that is 762mm. We divide that by the measurement we just did, which is 698mm. And then we get the scaling factor of 10.917. And the scaling factor we put in here and then we hit scale and then you can see how the 3D model is scaled up. And again we export the file as a STL file from NetFabb. The final step for the actual scan is to combine both 3D scans—the one sitting on the flange and the one upside down. For that again, we use MeshLab one by one we drag and drop them into the software. And you can see them now inside the software. And now we hit the yellow button up here with an A. And on the right side here we have the two scans. We select the upper 3D scan and click on glue mesh here, And then we select the lower 3D scan and click on point based gluing. And now this new window opens. And now we try to find distinctive features, which are similar in both scans because we are helping the computer to align both. This is by selecting points with numbers. You should at least select three points. And now we click on OK And the rough alignment has been done. And now, when we hit process, the detailed alignment will begin and also the computer will supply us with a global alignment error, which in this case is 0.001 Which is really good. The final step we again Select the parts that we don’’t really need the upper and lower part and hit the delete key. And now our scan is finished. The final step is to select both scans and flatten visible layers. And now we can export the 3D scan as a STL file. I told you that I also 3D scanned this part with a professional scanner. So now I want to show you the comparison between the two. In this animation, first, you can see in yellow rotating our 3D scan and then afterwards in green, you can see the professional scan that we did. This scan was made with the 3D scanner Artec Space Spider, a professional scanner, which costs about 20,000 Euros. It’’s a little cleaner. But you could expect that from a professional device. Now, Let’’s check how accurate the free 3D scan actually is in comparison to the professional scan. For that, we will use the software GOM Inspect Again drag and drop both 3D scans into the software. The free one and the professional one. Then we hit automatic pre-alignment. On the right side, you can now see an explanation. It’’s a gradient going from red over green to blue And well. If it’’s green, that means there’’s no deviation between our free scan and the professional scan If it’’s red that means there’’s material from the free scan above the professional scan and in the blue area. It’s the other way around. We also want to see in selected places, the deviation, and for that we can set deviation labels. These are like markers showing us in selected areas, the deviation between the two scans. And here you can see that the deviation is about 0.2 mm, between both scans on average, I will supply all files on our blog to download them – the free scan, the professional scan and also the report that that compares the two. On a final note Holocreator’s my company is a 3D scanning company. So we do 3D scans with photogrammetry structured light and even computed tomography—that’’s Xray Scanning—and. You get really accurate scans with that. So the accuracy range that we offer goes from 0.1 mm down to 0.005 mm, so we make highly accurate scans. So if you have a project where you need that kind of accuracy, please get in touch with us. Now that we have created a 3D scan for free for many of you, that might just be a first step in a long process of working with these files. Many of you may want to convert these STL files into a STEP files. For this, I have also prepared a tutorial called STL to STEP and in that, I will show you how to use free software to convert STL to STEP files.