Posts with «3d scanning» label

OpenScan 3D Scans All Of The (Small) Things

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.

Feature visualization overlays detected features onto the camera preview to help judge quality. Broadly speaking, green is good.

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.

Embedded below is a video that walks through the installation and web interface. It’s a fairly long and comprehensive, but if you like you can skip directly to [Thomas] demonstrating the interface around the 8:22 mark, or watch it below. Interested in your own unit? [Thomas] has an e-shop for parts and the GitHub repository is right here; the project also has its own subreddit.

Photogrammetry isn’t limited to small objects. We have seen some neat applications in the past, where it was the missing link to modeling a custom control panel and making a 3d scan of a custom-molded ergonomic trackball.

Manual 3D Digitizer Works a Bit Like 3-Dimensional Measuring Tape

Digitizing an object usually means firing up a CAD program and keeping the calipers handy, or using a 3D scanner to create a point cloud representing an object’s surfaces. [Dzl] took an entirely different approach with his DIY manual 3D digitizer, a laser-cut and 3D printed assembly that uses rotary encoders to create a turntable with an articulated “probe arm” attached.

Each joint of the arm is also an encoder, and by reading the encoder values and applying a bit of trigonometry, the relative position of the arm’s tip can be known at all times. Manually moving the tip of the arm from point to point on an object therefore creates measurements of that object. [Dzl] successfully created a prototype to test the idea, and the project files are available on GitHub.

We remember the earlier version of this project and it’s great to see how it’s been updated with improvements like the addition of a turntable with an encoder. DIY 3D digitizing takes all kinds of approaches, and one example was this unit that used four Raspberry Pi Zeros and four cameras to generate high quality 3D scans.

An Arduino-controlled turntable for 3D scanning

Many DSLR cameras can be operated with a simple infrared signal, making them perfect targets for Arduino control. Travis Antoniello took advantage of this with his brilliantly simple 3D scanning rig.

Electronics are handled by an Arduino Uno, which commands a stepper motor to rotate a scanning platform 10 degrees per photo. After rotation, it stops for a set amount of time to let scanned objects settle, and triggers the camera, a Nikon D3200, via an infrared LED. It then repeats this process over and over until a full set of photos is taken. 

Code for the build can be found on GitHub, and the device’s 3D-printed components are available on Thingiverse. The project video seen here gives a good overview of how it works, and the scanned object on display just after 2:30 looks absolutely brilliant.

Hackaday Prize Entry: Cheap, Open LiDAR

[adam] is a caver, meaning that he likes to explore caves and map their inner structure. This is still commonly done using traditional tools, such as notebooks (the paper ones), tape measure, compasses, and inclinometers. [adam] wanted to upgrade his equipment, but found that industrial LiDAR 3D scanners are quite expensive. His Hackaday Prize entry, the Open LIDAR, is an affordable alternative to the expensive industrial 3D scanning solutions out there.

The 3D scan of a small cave near Louisville from [caver.adam’s] Sketchfab repository
LiDAR — Light Detection And Ranging —  is the technology that senses the distance between a sensor and an object by reflectively measuring the time of flight of a light beam between the two. By acquiring a two-dimensional array of multiple distance readings, this can be used for 3D scanning. Looking at how the industrial LiDAR scanners capture the environment using fast spinning mirrors, [adam] realized that he could basically achieve the same by using a cheap laser range finder strapped to a pan and tilt gimbal.

The gimbal he designed for this task uses stepper motors to aim an SF30-B laser rangefinder. An Arduino controls the movement and lets the eye of the sensor scan an object or an entire environment. By sampling the distance readings returned by the sensor, a point cloud is created which then can be converted into a 3D model. [adam] plans to drive the stepper motors in microstepping mode to increase the resolution of his scanner. We’re looking forwards to see the first renderings of 3D cave maps captured with the Open LIDAR.

The HackadayPrize2016 is Sponsored by:

Filed under: The Hackaday Prize