Pint-sized Jacob’s Ladder Packs 10,000 Volts In A Pickle Jar

November 5, 2018 by Brian Boucheron 12 Comments

File this one away for your mad scientist costume next Halloween: [bitluni]’s Pocket Jacob’s Ladder is the perfect high voltage accessory for those folks with five dollars in parts, a 3D printer, and very big pockets.

[bitluni]’s video shows you all the parts you’ll need and guides you through the very simple build process. For parts, you’ll require a cheap and readily-available high-voltage transformer, a battery holder, some silver wire for the conductors, and a few other minor bits like solder and a power switch.

Once the electronics are soldered together, they’re stuffed inside a 3d printed case that [bitluni] designed with FreeCAD. The FreeCAD and STL files are all available on Thingiverse. We’re not sure what type of jar [bitluni] used to enclose the electrodes. If your jar isn’t a match, you’ll have to get familiar with FreeCAD or start from scratch with your favorite CAD package.

Either way, we enjoy the slight nod toward electrical safety and the reuse of household objects for project enclosures.

If you’re interested in a Jacob’s Ladder with significantly higher voltage we’ve got you covered, or we’ve also written about another tiny portable Jacob’s Ladder.

The full video is embedded after the break.

Continue reading “Pint-sized Jacob’s Ladder Packs 10,000 Volts In A Pickle Jar” →

Stepper Motor Mods Improve CNC Flat Coil Winder

November 4, 2018 by Dan Maloney 56 Comments

Finding just the right off-the-shelf part to complete a project is a satisfying experience – buy it, bolt it on, get on with business. Things don’t always work out so easily, though, which often requires the even more satisfying experience of modifying an existing part to do the job. Modifying a stepper motor by drilling a hole down its shaft probably qualifies for the satisfying mod of the year award.

That’s what [Russ] did to make needed improvements to his CNC flat-coil winder, which uses a modified delta-style 3D-printer to roll fine magnet wire out onto adhesive paper to form beautiful coils of various sizes and shapes. [Russ] has been tweaking his design since we featured it and coming up with better and better coils. While experimenting, the passive roller at the business end proved to be a liability. The problem was that the contact point lagged behind the center axis of the delta, leading to problems with the G-code. [Russ] figured that a new tool with the contact point at the dead center would help. The downside would be having to actively swivel the tool in concert with the X- and Y-axis movements. The video below shows his mods, which include disassembling the NEMA-17 stepper and drilling out the shaft to pass the coil wire. [Russ] also spent some time reversing the rotor in the frame and provided a small preload spring to keep the coil roller in contact with the paper.

A real-time coil winding session starts at the 21:18 mark, and we’ve got to admit it’s oddly soothing to watch. We’re not sure exactly what [Russ] intends to do with these coils, and by his own admission, neither is he. But it’s still pretty cool to see, and the stepper motor mods are a neat trick to keep in mind.

Continue reading “Stepper Motor Mods Improve CNC Flat Coil Winder” →

Save A Few Steps On Your Next Build With These Easy Linear Actuators

November 2, 2018 by Dan Maloney 18 Comments

A lot of projects require linear motion, but not all of them require high-accuracy linear slides and expensive ball screws. When just a little shove for a door or the ability to pop something up out of an enclosure is all you need, finding just the right actuator can be a chore.

Unless someone has done the work for you, of course. That’s what [Ali] from PotentPrintables did with these 3D-printed linear actuators. It’s a simple rack-and-pinion design that’s suitable for light loads and comes in two sizes, supporting both the 9-g micro servos and the larger, more powerful version. Each design has a pinion that has to be glued to a servo horn, and a selection of rack lengths to suit your needs. The printed parts are nothing fancy, but seem to have material in the right places to bear the loads these actuators will encounter. [Ali] has included parts lists and build instructions in with the STL files, as well as sample Arduino code to get you started. The video below shows the actuators in action.

We’re heartened to learn that [Ali] was at least partly inspired to undertake this design by a previous Hackaday post. And we’re glad he decided to share his version; it might save us a few steps on our next build.

Continue reading “Save A Few Steps On Your Next Build With These Easy Linear Actuators” →

A Cow-Powered Human Centrifuge

November 1, 2018 by Elliot Williams 46 Comments

Spoiler alert: group of fun-loving French folks build an animal-or-human-powered merry-go-round that spins fast enough to fling all takers into the lake (YouTube, embedded below). Actually, that’s basically it. The surprise is ruined, but you probably want to check out the video anyway, because it looks like a ton of fun.

Granted, you may not have a well-stocked metal shop or a team of oxen up by the lake wherever you live, but there are certainly details in the video that will survive in translation. Basically, the team took the axle off of a junked car, attached it to a pole in the middle of the lake, made a large wooden drive wheel, and wrapped an infinite length of rope around it.

[Charles] from [Mad Cow] wrote us that there was about a 10:1 ratio between the drive wheel and the arms of the people-flinger. So if the cattle were pulling at 3 km/h, the human angular velocity was a brisk 30 km/h! Then it’s just a matter of convincing a team of cows, or a team of soccer players (?), to put their backs into it.

The [Mad Cow] crew seems to have more than their fair share of ~~engineering~~ dangerous fun up at their summer hideaway: check out their human crossbow that we featured a few years back.

Continue reading “A Cow-Powered Human Centrifuge” →

Open Data Cam Combines Camera, GPU, And Neural Network In An Artisanal DIY Cereal Box

October 29, 2018 by Brian Boucheron 13 Comments

The engineers and product designers at [moovel lab] have created the Open Data Cam – an AI camera platform that can identify and count objects as they move through its field of view – along with an open source guide for making your own.

Step one: get out your ruler and utility knife. In this world of ubiquitous 3D-printers they’ve taken a decidedly low-tech approach to the project’s enclosure: a cut, folded, and zip-tied plastic box, with a cardboard frame inside to hold the electronic bits. It’s “splash proof” and certainly cheap to make, but we’re a little worried about cooling and physical protection for the electronics inside, as they’re not exactly cheap and rugged components.

So what’s inside? An Nvidia Jetson TX2 board, a LiPo battery with some charging circuitry, and a standard webcam. The special sauce, however, is the software, which is available on GitHub. [Moovel lab]’s engineers have put together a nice-looking wifi-accessible mobile UI for marking the areas where you’d like the software to identify and tally objects. The actual object detection and identification tasks are performed by the speedy YOLO neural network, a task the Nvidia board’s GPU is of course well suited for.

As the Open Data Cam’s unblinking glass eye gazes upon our urban environments, it will log its observations in an ancient and mysterious language: CSV. It’s up to you, human, to interpret this information and use it for good.

A summary video and build time lapse are embedded after the break.

Continue reading “Open Data Cam Combines Camera, GPU, And Neural Network In An Artisanal DIY Cereal Box” →

A Tour Through The Archetypical Asian Factory

October 28, 2018 by Kerry Scharfglass 51 Comments

Overseas factories can be sort of a mythical topic. News articles remind us that Flex (née Flextronics) employs nearly 200 thousand employees worldwide or that Foxconn is up to nearly a million. It must take an Apple-level of insider knowledge and capital to organize such a behemoth workforce, certainly something well past the level of cottage hardware manufacturing. And the manufacturing floor itself must be a temple to bead blasted aluminum and 20 axis robotic arms gleefully tossing products together. Right?

Well… the reality is a little different. The special sauce turns out to be people who are well trained for the task at hand and it doesn’t require a $1,000,000,000,000 market cap to get there.

[Adam leeb] was recently overseas to help out with the production ramp for one of his products and took a set of fantastic videos that walk us through an archetypical asian factory.

I’ve been to several factories and for me the weirdest part of the archetype is the soul crushing windowless conference room which is where every tour begins. Check out this one on the left. If you ever find yourself in a factory you will also find a room like this. It will have weird snacks and bottles of water and a shiny wood-esque table. It will be your home for many, many more hours than you ever dreamed. It’s actually possible there’s just one conference room in the universe and in the slice of spacetime where you visit it happens to be in your factory.

Ok, less metaphysics. It’s amazing to watch the myriad steps and people involved in taking one product from zero to retail-ready. [adam] gives us a well narrated overview of the steps to go from a single bare board to the fully assembled product. From The Conference Room he travels to The Floor and walks us through rows of operators performing their various tasks. If you’ve been reading for a while you will recognize the pick and place machines, the ovens, and the pogo pin test fixtures. But it’s a treat to go beyond that to see the physical product that houses the boards come together as well.

Check out [adam]’s videos after the break. The first deals with the assembly and test of his product, and the second covers the assembly of the circuit boards inside which is broadly referred to as SMT. Watching the second video you may notice the funny (and typical) contrast between the extremely automated SMT process and everything else.

Continue reading “A Tour Through The Archetypical Asian Factory” →

Kinetic Sculpture Achieves Balance Through Machine Learning

October 26, 2018 by Dan Maloney 9 Comments

We all know how important it is to achieve balance in life, or at least so the self-help industry tells us. How exactly to achieve balance is generally left as an exercise to the individual, however, with varying results. But what about our machines? Will there come a day when artificial intelligences and their robotic bodies become so stressed that they too will search for an elusive and ill-defined sense of balance?

We kid, but only a little; who knows what the future field of machine psychology will discover? Until then, this kinetic sculpture that achieves literal balance might hold lessons for human and machine alike. Dubbed In Medio Stat Virtus, or “In the middle stands virtue,” [Astrid Kraniger]’s kinetic sculpture explores how a simple system can find a stable equilibrium with machine learning. The task seems easy: keep a ball centered on a track suspended by two cables. The length of the cables is varied by stepper motors, while the position of the ball is detected by the difference in weight between the two cables using load cells scavenged from luggage scales. The motors raise and lower each side to even out the forces on each, eventually achieving balance.

The twist here is that rather than a simple PID loop or another control algorithm, [Astrid] chose to apply machine learning to the problem using the Q-Behave library. The system detects when the difference between the two weights is decreasing and “rewards” the algorithm so that it learns what is required of it. The result is a system that gently settles into equilibrium. Check out the video below; it’s strangely soothing.

We’ve seen self-balancing systems before, from ball-balancing Stewart platforms to Segway-like two-wheel balancers. One wonders if machine learning could be applied to these systems as well.

Continue reading “Kinetic Sculpture Achieves Balance Through Machine Learning” →