DIY Punch Card System Despite Hanging Chads

Sometimes you just have parts lying around and want to make something out of them. [Tymkrs] had a robot paper cutter, so naturally they made punch cards. But then, of course, they needed a punch card reader, so they made one of those too. All with stuff lying around the shop.

The Silhouette Portrait paper cutter is meant for scrapbooking, but what evokes memories of the past more than punchcards? To cut out their data, rather than cute kittens or flowers, they wrote some custom code to turn ASCII characters into rows of dots. And the cards are done — you just have to clean up the holes that didn’t completely cut. These are infamously known as hanging chads.

The reader is made up of a block of wood, with a gap for the cards and perpendicular holes drilled for LEDs and photoresistors. This is cabled to a Propeller dev board with some simple firmware. We would have used photodiodes or phototransistors, because that’s what’s in our junk box (and because they have faster reaction time), but when you’ve got lemons, make lemonade.

OK, now that you’ve got a punch card reader and writer, what do you do with it? Password storage comes to mind.

Continue reading “DIY Punch Card System Despite Hanging Chads”

Open Hybrid Gives you the Knobs and Buttons to your Digital Kingdom

With a sweeping wave of complexity that comes with using your new appliance tech, it’s easy to start grumbling over having to pull your phone out every time you want to turn the kitchen lights on. [Valentin] realized that our new interfaces aren’t making our lives much simpler, and both he and the folks at MIT Media Labs have developed a solution.

open-hybrid-light-color-pickerOpen Hybrid takes the interface out of the phone app and superimposes it directly onto the items we want to operate in real life. The Open Hybrid Interface is viewed through the lense of a tablet or smart mobile device. With a real time video stream, an interactive set of knobs and buttons superimpose themselves on the objects they control. In one example, holding a tablet up to a light brings up a color palette for color control. In another, sliders superimposed on a Mindstorms tank-drive toy become the control panel for driving the vehicle around the floor. Object behaviors can even be tied together so that applying an action to one object, such as turning off one light, will apply to other objects, in this case, putting all other lights out.

Beneath the surface, Open Hybrid is developed on OpenFrameworks with a hardware interface handled by the Arduino Yún running custom firmware. Creating a new application, though, has been simplified to be achievable with web-friendly languages (HTML, Javascript, and CSS). The net result is that their toolchain cuts out a heavy need for extensive graphics knowledge to develop a new control panel.

If you can spare a few minutes, check out [Valentin’s] SolidCon talk on the drive to design new digital interfaces that echo those we’ve already been using for hundreds of years.

Last but not least, Open Hybrid may have been born in the Labs, but its evolution is up to the community as the entire project is both platform independent and open source.

Sure, it’s not mustaches, but it’s definitely more user-friendly.

Continue reading “Open Hybrid Gives you the Knobs and Buttons to your Digital Kingdom”

Maglev, Submersibles, and More at Maker Faire Detroit

This past weekend the Maker Faire returned to the motor city. While it seemed a bit smaller than previous years, the event still brought in a ton of awesome makers from the metro Detroit area and beyond.

img_8517

Although we don’t feature too many woodworking projects, there were quite a few woodworkers at the Faire with projects ranging from custom longboards pressed with a home built iron mold to DIY kayaks with elaborate wooden skeletons built by a local group of Michigan kayak builders. The kayaks were quite impressive: hand sewn nylon panels are wrapped around custom frames made from steamed white oak. It’s great to speak with the makers about the specialized skills needed for kayak building.

Continue reading “Maglev, Submersibles, and More at Maker Faire Detroit”

We Should 3D Scan People

In a perfect futuristic world you have pre-emptive 3D scans of your specific anatomy. They’d be useful to compare changes in your body over time, and to have a pristine blueprint to aid in the event of a catastrophe. As with all futuristic worlds there are some problems with actually getting there. The risks may outweigh the rewards, and cost is an issue, but having 3D imaging of a sick body’s anatomy does have some real benefits. Take a journey with me down the rabbit hole of 3D technology and Gray’s Anatomy.

Continue reading “We Should 3D Scan People”

Ghost Guitar Plays Hendrix

Purple Haze all in my brain,
lately guitars they don’t seem the same,
[Josh] is playin’ funny but I don’t know why
‘scuse me while he electrifies.

[Josh] wanted to experiment with playing a guitar by different means. We’ve seen a few guitar hacks that use servos to play, and Arduino-based guitars that replace the strings with membrane potentiometers, but he decided to try a different approach. He’s using a permanent magnet and the electromagnetic effect to play the string.

Purple Haze all around,
all those amps are runnin’ up or down.
Are my strings all goin’ left or right?
Whatever it is, electromagnetism is pushin’ me outta sight.

To do this, he put a large permanent magnet next to the string and ran an alternating current through the string itself. When the current and the magnetic field interact, the string is pushed, like the bearing of a motor.  When the current goes the other way, the string is pushed in the opposite direction. Because he is using an alternating current (driven through a MOSFET tied into a frequency generator), he was able to control the frequency of this, and find the frequencies that made the string resonate, including the harmonics that give guitars their unique sound. It’s a pretty neat hack, but don’t forget that he is dealing with quite a lot of juice: if you were to inadvertantly touch the string and ground it to earth, there is enough current in the circuit to kill you.

Yeah, [Josh’s] hack is all about the right hand rule,
I know that he’s no hacking fool,
you’ve got my E string resonating, resonating so fine
just don’t touch it, or you’ll end your time
Help me, yeah, Purple Haze!

(with apologies to the ghost of [Jimi Hendrix], guitar hacker supreme)

Continue reading “Ghost Guitar Plays Hendrix”

The Biohacking Movement and Open Source Insulin

In March of 2014, I knew my eight year old daughter was sick. Once borderline overweight, she was now skeletally thin and fading away from us. A pre-dawn ambulance ride to the hospital gave us the devastating news – our daughter had Type 1 diabetes, and would be dependent on insulin injections for the rest of her life.

This news hit me particularly hard. I’ve always been a preparedness-minded kind of guy, and I’ve worked to free myself and my family from as many of the systems of support as possible. As I sat in the dark of the Pediatric ICU watching my daughter slowly come back to us, I contemplated how tied to the medical system I had just become. She was going to need a constant supply of expensive insulin, doled out by a medical insurance system that doesn’t understand that a 90-day supply of life-saving medicine is a joke to a guy who stocks a year supply of toilet paper. Plus I had recently read an apocalyptic novel where a father watches his 12-year old diabetic daughter slip into a coma as the last of her now-unobtainable insulin went bad in an off-grid world. I swore to myself that I’d never let this happen, and set about trying to find ways to make my own insulin, just in case.

Continue reading “The Biohacking Movement and Open Source Insulin”

One Way to Recharge Alkaline Batteries

It says it right on the side of every alkaline battery – do not attempt to recharge. By which of course the manufacturer means don’t try to force electrons back into the cell. But [Cody] figured he could work around that safety warning chemically, by replacing the guts of an alkaline dry cell.

The batteries in question were certainly old, gnarly looking, and pretty dead – [Cody] barely got a reading on his multimeter. As you can see after the break, he cleaned off the exterior corrosion and did a quick teardown of the dry cells, removing the remains of the zinc anode, now in the form of zinc oxide paste looking very much like what you’d slather on your nose before a day at the beach. He filled the resulting cavity with a putty of zinc dust, freshened up the electrolyte charge with a squirt of 20% potassium hydroxide, sealed up the cell with a little silicone caulking, and put the recycled cell to the test. Result: 1.27 volts. Not too shabby.

Continue reading “One Way to Recharge Alkaline Batteries”