Providing the magical ability to scan not only the surface, but also to reveal details of the insides of an object, the CT (computed tomography) scanner has quite literally changed the way we see ourselves.
Modern CT scanners are frightfully expensive and are usually found in hospitals but Canadian-born Peter Jansen has built one himself out of laser cut wood.
“After seeing the cost for my CT scan, I decided it was time to try to build an open source desktop CT scanner for small objects, and to do it for much less than the cost of a single scan.”
With a design quite similar to the early commercial CT scanners, Peter’s device began as a quarter-scale laser cut acrylic version that he whipped up in a single day.
He then used this mockup to help refine the design, under the watchful gaze of a friendly house cat. (more…)
OFFRobot design iterations resolved using laser cutting
Responding to the tempting possibilities posed by the Hack The Arduino Robot challenge, the OFFRobot is a neat little walker designed by John Rees from the UK.
He’s documented his development process and thoughts along the way, from design of the walking mechanism (including inspiration from Disney Research and the ever-impressive Strandbeest) through to various stages of laser cut and 3d printed leg assemblies.
One interesting point to note is that John’s prototyping went from laser cut cardboard in the early stages, on to laser cut plywood and then 3d printing which came into play once the design was more resolved.
With the deadline of the competition looming, he went back to laser cutting in acrylic for the final burst.
“I did more 3d printing. It gave me some great, really solid and light pieces but I left it too late to print everything, so I will revert to laser cutting once again!”
By ‘reverting’ back to laser cutting for the robot’s legs and gears, John was able to achieve reliable, accurate and tangible results really quickly. That’s one of the major advantages of laser cutting – the unrivalled speed and precision.
Here’s a look at how the OFFRobot mechanism works:
Imagine controlling a serious laser cutter with the dynamic ease of an Etch A Sketch. Having first toyed with the idea years ago, Just Add Sharks have finally followed through and attached a fully functional Etch A Sketch controller to their laser cutter. Talk about dreams coming true!
Complete with authentic twiddly knobs and retro-Etch styling (all laser cut, of course) the modification uses an Arduino Pro Mini to bypass the machine’s existing wiring.
Click through for a video of the controller in action, where you can see the different functionality of either Etch or Cut being demonstrated.
Keeping projects in balance with DIY robotic device
The Stewart platform is an ingenious robotic device that provides flexible movement of a working surface across six degrees of freedom. Often used to support flight simulators and telescopes, they are also an essential component of many serious university projects.
After observing that more time is often spent on preparing a reliable platform than on the project itself, Dan Royer has set out to build a standard platform that universities can make use of across a range of projects.
Large Stewart platforms use hydraulics to manipulate heavy loads quickly and precisely. Currently, Dan’s version works on a smaller scale using a platform built from laser cut wood with stepper motors providing motion control.
It is quite a challenge to deliver mechanical precision that is also strong and smooth when in motion. The test rigs that Dan has constructed are powered by Adafruit’s stepper motor controller boards, all driven by an Arduino. The task of keeping all six stepper motors working together is particularly tricky, so in pursuit of the most stable outcome the Gcode demo software is available as an open source download on github.
Maurice Ribble designs a hardware hit for fiber hobbyists.
Spinning wheels always bring to mind fairy tales: Rumpelstiltskin spinning straw into gold in exchange for a maiden’s first born child, Sleeping Beauty cursedly pricking her finger on the spindle.
But luckily, Maurice Ribble’s story isn’t so grim (pun intended.) Maurice is a computer engineer who lives with his wife Emily in the Boston area. “I always say my wife’s first love is knitting because she’s done it for much longer than she’s known me,” he says.
Emily often spins her own yarn for her knitting projects and totes a manual spinning wheel to her knitting group. “The mechanics of the spinning wheel were fascinating to my engineering mind and her need to travel with it gave me some great reasons to set about making a very portable, electric spinning wheel,” Maurice explains.
Soon he had requests from Emily’s friends to make them one too. “One thing lead to another, and now you can buy them on the internet,” he says. And lots of people are buying them.
Vintage technical publication still grooving after all those years
Before we had those nifty little electronic transistors to build nicknacks and devices out of, machines and the designers behind them relied on mechanical precision to perform tasks. Bringing to light the 1868 publication by Henry T Brown, 507 Movements reveals just how ingenious some of those mechanisms can be… and how relevant they are for today.
Even better than simply a trip down memory lane, this magical repository is just itching to be applied in some 21st century laser cutting projects.
In previous posts, we have taken a look at online 3D mechanical resources and the very handy Gear Template Generator that help to de-mystify mechanical devices. Both of these tools help to get gears working right, but what if you need a little help figuring out which gears or mechanisms to use? That’s where 507 Movements shines.
The movements are represented in both static and selected animated drawings that are kind of hypnotic yet educational at the same time.
To demonstrate how nifty geared mechanisms can be, we’ve included an impressive video after the break (assuming gears are what gets you groovin’) of some creative cogs in action. (more…)
Arduino has made it easier than ever before to build sophisticated electronics projects. That being said, there is still a significant learning curve for people who have absolutely no idea what they are doing when it comes to electronics.
This “Beginner’s Guide” for the Arduino by Brad Kendall is a great introduction. It starts from the very beginning and assumes no knowledge whatsoever. If you want to make something with an Arduino and you don’t know how a breadboard works, this is the guide for you. It will walk you through setup and your first couple projects.