The OpenScan project has been updated quite a bit since its inception. OpenScan is an open source, Arduino or Raspberry Pi-based 3D scanner for small objects that uses 3D printed hardware and some common electronic components to create 3D scans using photogrammetry; a process by which a series of still images from different angles are used to create a 3D point cloud of an object, which can then be used to generate a 3D model.
Photogrammetry is a somewhat involved process that relies on consistent conditions, so going through the whole process only to find out the results aren’t up to snuff can be tiresome. Happily, OpenScan offers some interesting new functions such as feature visualization via the web interface, which helps a user judge scan quality and make changes to optimize results without having to blindly cross their fingers quite so much. OpenScan remains a one-person project by [Thomas], who is clearly motivated to improve his design and we’re delighted to see it getting updates.
When the Raspberry Pi 4 came out, [Frank Zhao] saw the potential to make a realtime 3D scanner that was completely handheld and self-contained. The device has an Intel RealSense D415 depth-sensing camera as the main sensor, which uses two IR cameras and an RGB camera along with the Raspberry Pi 4. The Pi uses a piece of software called RTAB-Map — intended for robotic applications — to take care of using the data from the camera to map the environment in 3D and localize itself within that 3D space. Everything gets recorded in realtime.
This handheld device can act as a 3D scanner because the data gathered by RTAB-Map consists of a point cloud of an area as well as depth information. When combined with the origin of the sensing unit (i.e. the location of the camera within that area) it can export a point cloud into a mesh and even apply a texture derived from the camera footage. An example is shown below the break. Continue reading “Handheld 3D Scanning, Using Raspberry Pi 4 And Intel RealSense Camera”→
One of the best applications for desktop 3D printing is the creation of one-off bespoke components. Most of the time a halfway decent pair of calipers and some patience is all it takes to model up whatever part you’re after, but occasionally things get complex enough that you might need a little help. If you ever find yourself in such a situation, salvation might be just a few marker scribbles away.
As [Mangy_Dog] explains in a recent video, he wanted to model a control panel for a laser cutter he’s been working on, but thought the shapes involved were a bit more than he wanted to figure out manually. So he decided to give photogrammetry a try. For the uninitiated, this process involves taking as many high-resolution images as possible of a given object from multiple angles, and letting the computer stitch that into a three dimensional model. He reasoned that if he had a 3D model of the laser’s existing front panel, it would be easy enough to 3D print some replacement parts for it.
That would be a neat enough trick on its own, but what we especially liked about this video was the tip that [Mangy_Dog] passed along about increasing visual complexity to improve the final results. Basically, the software is looking for identifiable surface details to piece together, so you can make things a bit easier for it by taking a few different colored markers and drawing all over the surface like a toddler. It might look crazy, but all those lines give the software some anchor points that help it sort out the nuances of the shape.
Unfortunately the markers ended up being a little more permanent than [Mangy_Dog] had hoped, and he eventually had to use acetone to get the stains off. Certainly something to keep in mind. But in the end, the 3D model generated was accurate enough that (after a bit of scaling) he was able to design a new panel that pops right on as if it was a factory component.
It’s possible to have an enjoyable weekend touring a city with a stolen cardboard cutout from some advertising display or other. However, it’s 2019, and 3D printing means you can go so much further. [Simon] of RCLifeOn went so far as to print a lifesized body double of himself, and it’s only slightly creepy! (Video, embedded below.)
The model was sourced from a 3D scan [Simon] had done with commercial hardware. An Optimus P1 industrial-grade 3D printer was used to print the parts, with total printing time being around 200 hours. Adhesive was used to join the various segments together, and the assembly was then sanded and primed, ready for paint.
Unwilling to tackle the task alone, [Simon] enlisted a professional painter to help put the finishing touches on the piece. The end result is impressive, particularly from a distance. [Simon 2.0] was then sent out to the city centre, aiming to raise money from bewildered passers by.
We suspect the market for custom body doubles will only increase as the technology to create them becomes more widespread. If you’ve tackled a similar project, be sure to let us know. Video after the break.
It seems 3D printers have been around for ages and still we don’t have a good solution for turning physical 3D objects into digital ones. Yes, 3D scanners exist, but the OpenScan is the best 3D scanner we’ve seen. It’s a 3D printed device meant to take pictures of an object that can then be used by photogrammetry software to construct a point cloud. From there, it’s just a matter of messing with meshes to create a 3D printed copy of anything you want.
The latest version of the scanner is an improvement over the previous version that kind of, sort of looked like the Machine from Contact. This was a gigantic hubless ring, with a smartphone attached to the rim. Put an object in the center, and the phone would rotate around the object in every axis, snapping pictures the entire time. Needless to say, a simpler design prevailed. That doesn’t mean the old version didn’t look awesome. The electronics are simply an Arduino clone, two stepper drivers, a character display for control and some headers for connections and power supplies. This is pretty normal stuff for the RepRap crew.
Running this machine is as simple as putting an object in the device and taking a few pictures. There is some support for remotely controlling some cameras, but everything is universal if you have a remote shutter release. This can be plugged into the electronics, and once everything is done you have a few dozen pictures of an object with optimal lighting conditions that can be thrown into your photogrammetry software of choice. (Ed note: at least one that doesn’t rely on the object remaining stationary with respect to the background to estimate camera position.)
Not long ago, photogrammetry — the process of stitching multiple photographs taken from different angles into a 3D whole — was hard stuff. Nowadays, it’s easy. [Mikolas Zuza] over at Prusa Printers, has a guide showing off cutting edge open-source software that’s not only more powerful, but also easier to use. They’ve also produced a video, which we’ve embedded below.
Basically, this is a guide to using Meshroom, which is based on the AliceVision photogrammetry framework. AliceVision is a research platform, so it’s got tremendous capability but doesn’t necessarily focus on the user experience. Enter Meshroom, which makes that power accessible.
Meshroom does all sorts of cool tricks, like showing you how the 3D reconstruction looks as you add more images to the dataset, so that you’ll know where to take the next photo to fill in incomplete patches. It can also reconstruct from video, say if you just walked around the object with a camera running.
The final render is computationally intensive, but AliceVision makes good use of a CUDA on Nvidia graphics cards, so you can cut your overnight renders down to a few hours if you’ve got the right hardware. But even if you have to wait for the results, they’re truly impressive. And best of all, you can get started building up your 3D model library using nothing more than that phone in your pocket.
If you want to know how to use the models that come out of photogrammetry, check out [Eric Strebel]’s video. And if all of this high-tech software foolery is too much for you, try a milk-based 3D scanner.
In its most basic sense, photogrammetry refers to taking measurements from photographs. In the sense being discussed here, it more precisely refers to the method of creating a 3D model from a series of photographs of a physical object. By taking appropriate images of an object, and feeding them through the right software, it’s possible to create a digital representation of the object without requiring any special hardware other than a camera.
[Eric] shares several tips and tricks for getting good results. Surface preparation is key, with the aim being to create a flat finish to avoid reflections causing problems. A grey primer is first sprayed on the object, followed by a dusting of black spots, which helps the software identify the object’s contours. Camera settings are also important, with wide apertures used to create a shallow depth-of-field that helps the object stand out from the background.
With the proper object preparation and camera technique taken care of, the hard work is done. All that’s then required is to feed the photos through the relevant software. [Eric] favors Agisoft Metashape, though there are a variety of packages that offer this functionality.