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DIY Conductive Paint For All Your Wearable Needs

DIY Conductive Paint

Conductive ink or paint is lots of fun. It opens up tons of possibilities for flexible and unique circuits — unfortunately, it’s pretty expensive. [Brian McEvoy] shows us how to make your own for cheap, and it works great!

He started trying to formulate his own recipe after playing with other Instructable guides and commercially available paint, and what he found is it’s really not that complex! Graphite powder, acrylic paint, and a jar with an airtight seal — seriously, it’s that simple! But, like any engineer worth their salt (he calls himself the 24 Hour Engineer), he had to do some tests to compare his formula.

In a detailed experiment he compares his formula to the commercially available Wire Glue, and two other recipes using Elmer’s Glue-All and graphite, and Titebond III with graphite. The results? Acrylic paint and graphite produce the most conductive material — and the cheapest!

Now that you can make conductive ink, why not 3D print a circuit stamp to make your very own SMD circuit board!

Monster 100W LED Flashlight Produces a Whopping 8500lm!

100W LED Flashlight

[Yannick] got a hold of a 100W LED diode recently, and like any self-respecting hacker, he just had to turn it into a ridiculously over powered flash light.

The tricky thing about these diodes is that they need a high amount of DC voltage, anywhere from 32-48V typically. [Yannick's] using a 12V sealed lead acid battery coupled with a 600W constant current boost converter which ups it to 32V at around 3.2A. He also managed to find a giant aluminum heat-sink to keep the diode from getting too hot. A 120mm fan helps to keep the heat sink nice and cool, which allows the light to be run constantly without fear of burning it out. But just in case he also has an Arduino monitoring the temperatures — oh and it provides PWM control to adjust the brightness of the light!

To focus the flashlight he bought a proper lens and reflector which can be mounted directly to the diode. At full power the LED puts out around 8500lm, which is brighter than almost all consumer projectors available — or even the high beams of a car!

[Read more...]

What Could You Do With 7 Fingers?

7 finger robotic glove

A strange thought yes, but MIT researchers think an extra two digits could really make a difference in many people’s lives. And as it turns out, having an extra robotic grasp allows you to do quite a few things single handed.

The extra two fingers provide three degrees of freedom each, and are mounted off the user’s wrist. A series of position recording sensors attached to the glove provide feedback to the system in order to control the fingers naturally, just by using your hand normally.

They taught the algorithm that controls the fingers by trying to pick up different (large) items using the hand and manually positioning the fingers. What they discovered is almost every grasp could be demonstrated as a combination of only 2-3 grip patterns.  [Read more...]

Spot Welder; Don’t Buy It, Build It

Spot Welder

Spot welders are super handy for making sheet metal enclosures for your projects. The problem is, commercial ones are rather expensive… The good news is, they’re actually really easy to make! This is [Caio Paulucci's] first submission to Hack a Day, and it was a weekend project him and his father just finished.

A spot welder works by dissipating large amounts of heat in between two electrodes in the material you are bonding. It makes use of a transformer that converts mains voltage to a very low voltage, but high current energy source. The cool thing with this type of welder is it’s perfectly safe to hold onto the electrodes as the voltage is so low, you won’t get electrocuted. By running a super high current (generally >1000A @ ~1-2V) through a small surface area, you can super heat most materials hot enough to weld them together.

They can be made using the transformer from a microwave, some heavy duty welding wire (generally 2/0 or thicker), and a few other odds and ends such as wood, electrodes, and maybe a few nuts and bolts. At the most basic level, you are basically re-wrapping the transformer’s secondary coils to change the ratio to produce a low voltage, high current transformer.

[Read more...]

I’m Sorry Dave, I’m Afraid I can’t Do That

HAL9000 Personal Computer

“Let me put it this way, Mr Amer. The 9000 series is the most reliable computer ever made. No 9000 computer has ever made a mistake or distorted information. We are all, by any practical definition of the words, foolproof and incapable of error. “

With that in mind, who wouldn’t want a HAL 9000 personal computer at home? For his latest project, [Eduardo Zola] brings us a very realistic Raspberry Pi powered HAL 9000, complete with an all seeing eye.

In case you’re not familiar (boo!) HAL 9000 is a character from 2001: a Space Odyssey. His name is an acronym for a Heuristically programmed ALgorithmic sentient computer who is responsible for controlling the Discovery One spacecraft, and well, he goes crazy.

[Eduardo] has built this replica out of wood, a bit of paint, a Raspberry Pi, a speaker, webcam and a beautiful red all-seeing-eye, lit with LEDs. It’s a rather fitting entry to our Hackaday Prize contest.

[Read more...]

800+ LED Wall With Diffuser Panel is a Work of Art

LED Wall

What happens when you take over 800 individually addressable super bright RGB LEDs and house them in a giant diffused panel? You get awesome. That’s what you get.

[Epoch Rises] is a small electronic music and interactive technology duo who create cool interactive projects (like this wall) for their live shows and performances. They love their WS2812B LEDs.

The cool thing about this wall is that it can take any video input, it can be controlled by sound or music, an iPad, or even generate random imagery by itself. The 800 LEDs are controlled by a Teensy 3.0 using the OctoWS2811 library from Paul Stoffregen which is capable of driving over 1000 LEDs at a whopping 30FPS using just one Teensy microcontroller. It works by using Direct Memory Access to send data over serial into the Teensy’s memory and directly out to the LEDs with very little overhead — it is a Teensy after all!

[Read more...]

High Speed Laser Based Camera Flash Trigger for Only $2

Laser Triggered Camera Flash

[Matt Kane] works at a really cool company in the UK where he recently finished working on the Triggertrap Ada — the highest-performance, most feature packed camera trigger out there. So just for fun, he decided to challenge himself again — could he make a super basic, super fast, bare-bones camera trigger for $2 instead?

At the most basic level this is just a laser pointer and a light sensor. When the object your photographing breaks the light path, the flash triggers. Typically this is done with an IR laser, but since he’s going for a low-cost system, he’ll use a basic 1mw red laser pointer — the only downfall is you might see it in the picture.

Next up is the sensor. Ideally we’d use a photodiode which is very fast, but also expensive. A photoresistor is cheap, but not fast enough. A nice medium between the two is a phototransistor, which is relatively fast, and cheap. Finally, we need a minimum trigger period to offset the flash. [Matt] thought about using a 555 timer but instead decided to just generate a pulse with an Attiny45.  [Read more...]