3D scanning and Scan to BIM is one of the fastest growing segments of the construction industry, be it in the industrial sector or the commercial sector.
There are many competing technologies and techniques that seem to pop-up every day, photogrammetry, time of flight (depth-sensing) based scanning, and of course laser scanning are the three dominant technologies currently in use and development.
Being a small business in a developing nation, laser scanners were out of our price range, so we’ve opted for the first two techniques; photogrammetry and depth-sensing based scanners (Later we’ve tried testing Intel D515). We’ve dappled with photogrammetry but the process require huge computing power as well as very laborious photo-shoots, so we’ve decided to test the Intel RealSense platform.
Intel RealSense for scanning
This review will focus only on using the Intel RealSense D415 as a scanner and not for any other application ( robotics, object tracking, etc.).
At the time of deciding which camera to buy (late 2018), two main cameras were available; the Intel D415 and the Intel D435, other cameras like SR300 were nearly discontinued.
After doing our due diligence (prolonged research) we’ve found that the results from the D415 were better than the D435, it has less distortion and an overall better scan quality without many voids.
The first challenge we’ve faced was the SDK from Intel, the new SDK (V2) doesn’t have any scanning application unlike the old SDK. You can scan and get a .bag file.
First, the size of the file is huge, second, you can’t convert it to a point cloud, we’ve tried every trick using ROS, MATLAB, etc. and non was successful.
We had to rely on third-party software like Dot3D and RecFusion, there will be a separate post covering each of the software in details, for now, you’ve to understand that you can’t use the SDK to get an STL for 3D printing or a point cloud of the scan that you can use later in your BIM Software.
It’s also worth noting that you can capture a still STL using the SDK, it is like a photo but with some depth data, if that is what you seek.
Small Scans with Intel RealSense D415
We’ve tried using both software (Dot3D and Recfusion) to scan small mechanical spare parts and instrumentation, the results were very bad (nearly unusable) in any professional capacity, the scans were so bad that I can’t include in this post, it was nothing but a blob.
Large Scans with Intel RealSense D415
We had better results with larger scans, again none of them could be professionally submitted to a client, results from Dot3D (as seen below) were better but again not for professional use. The more complex the area we were trying to scan the more voids and the more cumbersome the scan becomes. we’ve even returned to photogrammetry as for many scans the results were better and the process was easier.
Intel RealSense D415 Bottom Line
If you want to use the Intel RealSense D415 in a professional capacity for complex site scans, it is better to seek an alternative, but if you want to scan a room or a simple space then it is a good option. In the coming posts, I’m going to compare between RecFusion and Dot3D.