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In early 2013 we were trying to verify the specifications of a parabolic dish we used in concentrating solar photovoltaic applications. The cheapest 3D scanner that was reliable cost $20,000. So we set out to build our own and, four prototypes later, we decided that this was an important problem to solve and in the process became obsessed about point-clouds.
When we began work on the Eora 3D scanner, our goal was to make sure it was precise and easy to use. We considered every element that defined professional 3D scanners – the processors, cameras, build quality, turntable design, projected light scanners and laser-based scanners.
Of course, there are all kinds of 3D scanners today – from projected light scanners that connect via a tablet that are handheld and fast, to traditional flat-bed/turntable scanners that are too often slow and stationary – but none is accurate, unless you have a lot of money to spend. So we challenged ourselves to design and engineer a 3D scanner that not only was extremely precise and accurate but also fast, portable and affordable.
Eventually we realised that the solution to our needs was sitting in our pockets. By harnessing the power and optics of a modern smartphone, we knew we could reduce our part-count and invest instead in the one part that makes high-precision scanning possible – a green laser.
Most consumer 3D scanners use a red laser, but digital camera CMOS sensors are twice as sensitive to the green spectrum as they are to red. This means you can scan in a variety of lighting conditions, even outdoors. Admittedly, a green laser costs almost three times as much as a standard red laser.
But when you have a smartphone that does all the heavy lifting, it means costs can be saved on the camera and processor and instead invested in other areas like the laser optics and powerful algorithms for the app.
The result is the Eora 3D scanner, a cylindrical device that connects to a phone via Bluetooth and uses a laser to scan the object in precise colour, and then allows the phone to analyse the laser and reconstruct the scan into a 3D model.
The scanner can connect to smartphones via Bluetooth 4.0, with a free 3D app available from the iOS app store and Google Play store. The precision of the scanner is sub-100 microns, with images captured in full-colour and rendered on-screen.
It is possible to scan up to a range of 1m and, based on a typical smartphone camera’s field of view, this means it is possible to capture 1m2 in one scan. For objects that are larger, it is possible take multiple scans and stitch them in-app or on compatible desktop software. A ¼-inch 20 UNC thread is included in the bottom for easy mounting on tripods.
A typical scan with the Eora 3D scanner takes just 5 minutes. And the result is displayed right on the screen. Unlike other 3D laser scanners, Eora doesn’t require a turntable because the app stitches together multiple scans from various angles to create a full model. Turntables can make scanning smaller objects easier, however, so we created an optional companion wireless turntable that connects to Eora via Bluetooth.
So what does this mean for engineers? Well, whether it’s a clay model or a custom figurine, you can digitise it within minutes. And it can be done at an affordable cost – the plan is to price the 3D scanner at $199 and the Bluetooth turntable at $259.