Lego Plays Electronic Drums

The ability to quickly try out an idea, and then expand and develop it, is what rapid prototyping is all about. Although we tend to think of 3D printing when rapid prototyping is mentioned, [Brick Technology] reminds us of the power of Lego, as he rapidly builds and improves an electromechanical drum machine.

Using Lego Technic pieces, he starts with a simple music box-style drum with moveable pins that pluck on spring-loaded levers, which in turn hit piezoelectric discs. The electronics side is simple, with the discs wired to a Roland sound module from an existing electronic drum kit. With the ability to instantly adjust, add and remove pieces, he quickly finds and fixes the problem of getting eleven hammer mechanisms together and working smoothly.

To get around the limited pin space on the drum and increase the length and variation potential of the rhythms, [Brick Technology] moved to a belt design that can accommodate significantly more pins. He also added an electric motor and various gearbox ratios for consistent and adjustable tempo. Together with his water vortex ball machine, he makes us think our workshops probably need a few hundred Lego Technic pieces.

Continue reading “Lego Plays Electronic Drums”

Used Facemasks Turned Into Rapid Antigen Tests With Injection Molding

Here’s a little eye-opener for you: next time you’re taking a walk, cast your eyes to the ground for a bit and see how far you can go without spotting a carelessly discarded face mask. In our experience, it’s no more than a block or two, especially if you live near a school. Masks and other disposal artifacts of the COVID-19 pandemic have turned into a menace, and uncounted billions of the things will be clogging up landfills, waterways, and byways for decades to come.

Unless they can be recycled into something useful, of course, like the plastic cases used for rapid antigen tests. This comes to us by way of [Ric Real] from the Design and Manufacturing Futures lab at the University of Bristol in the UK. If any of this sounds or looks familiar, refer back to October when the same team presented a method for turning old masks into 3D printer filament. The current work is an extension of that, but feeds the polypropylene pellets recovered from the old masks into a desktop injection molding machine.

The injection molding machine is fitted with 3D-printed molds for the shells of lateral flow devices (LFD) used for COVID-19 rapid antigen testing. The mold tooling was designed in Fusion 360 and printed on an Elegoo Mars MSLA printer using a high-strength, temperature-resistant resin. The molds stood up to the manual injection molding process pretty well, making good-quality parts in the familiar blue and white colors of the starting material. It’s obviously a proof of concept, but it’s good to see someone putting some thought into what we can do with the megatonnes of plastic waste generated by the pandemic response.

Rapid Prototyping Hack Chat

Join us on Wednesday, June 10 at noon Pacific for the Rapid Prototyping Hack Chat with Erika Earl!

When one thinks of the Jet Propulsion Lab, the NASA lab responsible for such amazing feats of engineering as Mars rovers and galaxy-exploring spacecraft like Voyager, one does not necessarily think of it as a hotbed of medical innovation. But when the COVID-19 pandemic started its march around the globe, JPL engineers decided to turn their skills from exploring other worlds to helping keep people alive in this one. Fittingly, the challenge they tackled was perhaps the most technically challenging: to build a ventilator that’s simple enough to be built in large numbers, enough to make a difference to the predicted shortfall, but that does the non-trivial job of keeping people breathing as safely as possible.

The result was VITAL, or Ventilator Intervention Technology Accessible Locally. It was designed, prototyped, and tested on an incredibly ambitious timetable: 37 days total. That number alone would be shocking enough, but when one adds in the disruptions and disconnection forced on the team of JPL engineers by the sudden need to self-isolate and work remotely that came up in the middle of the design process, it’s a wonder the team was able to get anywhere. But they worked through the technical and managerial issues and delivered a design that has now been licensed out to eight manufacturers under a no-fee license.

What does it take to bring something as complex as a ventilator to market in so short a time? To delve into that question, Supply Frame’s Erika Earl, who was part of the VITAL team, will stop by the Hack Chat. We’ll talk to her about being on the JPL team, what the design and prototyping process was like, and how the lessons learned here can apply to any team-based rapid-prototyping effort. You may not be building a ventilator in 37 days, but chances are good you can learn something useful from those who did.

join-hack-chatOur Hack Chats are live community events in the Hackaday.io Hack Chat group messaging. This week we’ll be sitting down on Wednesday, June 10 at 12:00 PM Pacific time. If time zones have you down, we have a handy time zone converter.

Click that speech bubble to the right, and you’ll be taken directly to the Hack Chat group on Hackaday.io. You don’t have to wait until Wednesday; join whenever you want and you can see what the community is talking about.
Continue reading “Rapid Prototyping Hack Chat”

Rapid Prototyping System Gives Wheels To Wearables

Wearables are kind of a perplexing frontier for electronics. On the one hand, it’s the best possible platform for showing off a circuit everywhere you go. On the other hand, the whole endeavor is fiddly because the human body has no straight lines and moves around quite a bit. Circuits need to be flexible and comfortable. In other words, a wearable has to be bearable.

[Konstantin], [Raimund], and [Jürgen] have developed an intriguing system for prototyping e-textiles that opens up the wearables world to those who don’t sew and makes the prototyping process way easier for everyone.

It’s a small and portable roll-on ironing device that lays down different kinds of custom ‘tapes’ on to textiles. The conductive fabric tapes can be used as touchable traces, and can support components such as flexible e-ink screens and solar panels. Some tapes provide single or multiple points of connectivity, and others are helper substrates like polyimide tape that multiply the possibilities for complex circuits.

The device uses a modified soldering iron to transfer the tapes, which are loaded onto 3D-printed spools that double as the wheels. Check it out after the break — there’s a 30-second tour and a 5-minute exploration of the whole process.

Everyone needs to prototype, even the seasoned stitchers. The next time you’re thinking in thread, throw some magnets into the process.

Continue reading “Rapid Prototyping System Gives Wheels To Wearables”

Magnets Make Prototyping E-Textiles A Snap

How do you prototype e-textiles? Any way you can that doesn’t drive you insane or waste precious conductive thread. We can’t imagine an easier way to breadboard wearables than this appropriately-named ThreadBoard.

If you’ve never played around with e-textiles, they can be quite fiddly to prototype. Of course, copper wires are floppy too, but at least they will take a shape if you bend them. Conductive thread just wants lay there, limp and unfurled, mocking your frazzled state with its frizzed ends. The magic of ThreadBoard is in the field of magnetic tie points that snap the threads into place wherever you drape them.

The board itself is made of stiff felt, and the holes can be laser-cut or punched to fit your disc magnets. These attractive tie-points are held in place with duct tape on the back side of the felt, though classic double-stick tape would work, too. We would love to see somebody make a much bigger board with power and ground rails, or even make a wearable ThreadBoard on a shirt.

Even though [chrishillcs] is demonstrating with a micro:bit, any big-holed board should work, and he plans to expand in the future. For now, bury the needle and power past the break to watch [chris] build a circuit and light an LED faster than you can say neodymium.

The fiddly fun of e-textiles doesn’t end with prototyping — implementing the final product is arguably much harder. If you need absolutely parallel lines without a lot of hassle, put a cording foot on your sewing machine.

Continue reading “Magnets Make Prototyping E-Textiles A Snap”

3D Printed Spuds Are Begging To Be Fired

The ballistics of humble potato is a time-honoured research topic for everyone who likes things that go bang. The focus of such work is usually on the launcher itself, with the projectiles being little more than an afterthought. [drenehtsral] decided that the wares of the local organic ammunition supplier were not good enough for him and his minions, so he designed and then 3D printed some rifled potato cannon slugs.

The design was done using OpenSCAD, has a number of adjustable parameters like infill and rifling. We doubt that the rifling introduces any spin, since it is being fired from a smooth bore barrel, but as always 3D printing brings the capability to quickly test different ideas. A quick search on Thingiverse shows a number of 3D printed spuds, so [drenehtsral] is not the first give it a go. However, this did bring to our attention that the field of spud gun projectiles is begging to be explored.

There is enough space inside a projectile to fit an IMU and logging electronics, which would give some very nice empirical data (providing you can recover it of course) on spin, acceleration, and trajectory that can be used to further improve designs. Spring loaded stabilising fins would be cool, and maybe someone can even manage to implement some form of guidance? The possibilities are endless! If you’re up for the challenge, please document your work it and let us know.

As you would expect we have no shortage of potato cannon themed content, ranging from cartridge firing and bolt action versions to antenna launchers and Arduino-powered fire control systems.

Rapidly Prototyping Prosthetics, Braille, And Wheelchairs

We live in an amazing time where the availability of rapid prototyping tools and expertise to use them has expanded faster than at any other time in human history. We now have an amazing ability to quickly bring together creative solutions — perfect examples of this are the designs for specialized arm prosthetics, Braille printing, and custom wheelchair builds that came together last week.

Earlier this month we published details about the S.T.E.A.M. Fabrikarium program taking place at Maker’s Asylum in Mumbai. The five-day event was designed to match up groups of makers with mentors to build assistive devices which help improve the condition of differently-abled people.

The participants were split into eight teams and they came up with some amazing results at the end of the five-day program.

Hands-On: Prosthetic Designs That Go Beyond

Three teams worked on projects based on Bionico – a myoelectric prosthesis

DIY Prosthetic Socket – a Human Machine Interface : [Mahendra Pitav aka Mahen] lost his left arm during the series of train bomb blasts in Mumbai in 2006, which killed 200 and injured over 700 commuters. He uses a prosthetic arm which is essentially a three-pronged claw that is cable activated using his other good arm. While it is useful, the limited functionality restricted him from doing many simple things. The DIY Prosthetic socket team worked with [Mahen] and [Nico Huchet] from MyHumanKit (who lost his right arm in an accident 16 years back), and fabricated a prosthetic forearm for [Mahen] with a modular, 3D printed accessory socket. Embedded within the arm is a rechargeable power source that provides 5V USB output at the socket end to power the devices that are plugged in. It also provides a second port to help recharge mobile phones. Also embedded in the arm was an IR reflective sensor that can be used to sense muscle movements and help trigger specific functions of add-on circuits, for example servos.

Continue reading “Rapidly Prototyping Prosthetics, Braille, And Wheelchairs”