Makers

We’ve held out for far too long. Hackaday now needs a 3D printer.   We get emails all the time asking why we don’t have a donate button. Well, we’re kind of stubborn and would rather just do with what we have. Unfortunately this hasn’t gotten us very far in the 3d printer department.

We have a few projects in mind that could really utilize a 3d printer, namely building custom game controllers for children with special physical needs.

If you have any interest in helping us get a 3D printer for Hackaday, read on. Otherwise, carry on with your day.

OK, we don’t like people giving us money for nothing, it feels icky. So, we’ve inflated the cost of a couple items in our store that you can purchase to help get us to our goal of $2500.  We have a sticker for $10, and you can preorder a 3D printed Hackaday badge for $25.  Being able to send you something for your money, even if it is just a token, makes us feel a little better.

Why don’t you just start a kickstarter?

I am so very very very sick of getting kickstarter emails. I choose to avoid that place.  If you’re reading hackaday, you’re our target audience anyway.

What printer do you want?

We’ve looked at the Ultimaker, Solidoodle, and Makerbot Replicator. At this point, our decision will be based on how much money we raise. If we can afford it we’ll most likely go with the Ultimaker. They’re crazy fast and the quality was pretty amazing.

“Don’t you think a 3D printer company would love to give you a printer just for the exposure?”

Sure, they might. That seems weird and somehow lacking in integrity though. I’m not sure why, I mean we’re begging our readers for money instead. Also, we haven’t asked any.  Maybe they’ll see this and offer.

“Why should we give you money?”

You probably shouldn’t. We’re not responsible people.

“why don’t you just build a reprap? They’re great!”

There are no less than 3 repraps owned by friends of ours that we could mooch off of. None of which can produce a high quality and consistent print. It is most likely just an issue of putting in the time to get everything dialed in perfectly. We don’t want to have to fight the printer.

I really really want to donate instead of buying your crap.

OK, only this once. You can just send money to my([Caleb]) personal paypal ( info@thebrickroomonline.com)

Filed under: 3d Printer hacks, news

Pete Prodoehl of Milwaukee Makerspace built this fruit-based noisemaker: A few months ago a bunch of us from Milwaukee Makerspace took part in Bay View Gallery Night, and jason set up the “Fruit Synthesizer” which was a Makey Makey with a variety of fruit, and some software combo of Max [...]

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It turns out that the Nexus 7 Android tablet is the perfect size to fit in a double DIN opening. DIN is the form factor of a single CD head unit for an automobile. Many models have room for a double DIN, which is defined as 4″ high by 7″ wide. Once [Meta James] figured out that the dashboard bezel for his Subaru framed the Nexus 7 perfectly he set out to fabricate the mounting system for an in-dash tablet installation.

Unlike a lot of these dashboard tablet installs, [James] didn’t need any Bondo, sanding, or painting to get things to look right. Like we mentioned, the bezel is a perfect fit so his alterations are hidden behind the tablet itself. He removed the stock head unit and ordered a DIN adapter kit to get the black bracket plate seen above. He built an acrylic box the same size as a double DIN head unit, then mounted the plates to the sides and a Nexus 7 case to the front. This holds the tablet in firmly, lets him mount the entire assembly using the factory mounting points, and leaves plenty of room for the cabling that connects the device to the car. Since he already had a hands-free phone system he just uses that to amplify the audio fed to it via Bluetooth.

[via Reddit]

Filed under: android hacks, transportation hacks

[Kory] has been experimenting with genetic algorithms. Normally we’d expect his experiments to deal with tuning the variables in a control system or something, but he’s doing something much cooler. [Kory] is using genetic algorithms to write computer programs, and in the process bringing us one step closer to the Singularity.

The first experiments with genetic algorithms generating applications did so in BASIC, C, and other human-readable languages. While these programs nearly worked, there were far too many limitations on what could be produced with a GA. A simpler language was needed, and after turning to assembly for a hot second, [Kory] ended up using brainfuck, an extremely minimal but still Turing-complete language.

The use of brainfuck for creating programs from a genetic algorithm may seem a bit strange, but there’s a method to [Kory]‘s madness. It’s relatively simple to write an interpreter the GA’s fitness function can look into and come up with a score of which programs should breed and which should die. Also, the simplicity of brainfuck means a computer doesn’t have to learn much syntax and grammar at all.

Right now, [Kory]‘s computer that can program itself only does so by creating simple ‘hello world’ programs. It should be possible, though, for this AI to create programs that take user input and generate an output, whatever that may be. Once [Kory] is able to have the computer generate its own fitness functions, though, the sky is the limit and the Singularity will be fast approaching.

Filed under: Software Development

Cheap toy pianos don’t usually have MIDI, and getting a velocity-sensitive keyboard from something out of the toy aisle at Walmart is nearly out of the question. If you’re willing to tear one of these toy pianos apart and build your own control electronics, though, the sky is the limit, as [JenShen] shows us with his home built velocity sensitive keyboard.

Usually, velocity-sensitive keyboards have two buttons underneath each key. By having a microcontroller measure the time difference between when each button is pressed, it’s possible to sense how fast each key was pressed. [JenShen] took the idea of a velocity-sensitive keyboard in another direction and instead used a force sensitive resistor strip, cut up into many pieces to provide velocity and aftertouch data.

[JenShen]‘s keyboard adds these resistive buttons to the button matrix he already made. The result is a very inexpensive velocity sensitive keyboard with aftertouch, an impressive feat for an Arduino and only a few components.

You can check out the keyboard in action after the break.

Filed under: musical hacks

Odds are you don’t have a photographic memory, so if you ever have to mace someone, you probably won’t remember exactly what your attacker looks like. Compound that with talking to the police and looking at a few dozen mug shots, and it’s highly unlikely you’ll ever be able to identify the person you maced. This was the problem [John], [Cordelia], and [Adrian] chose to solve for [Bruce Land]‘s microcontroller course at Cornell this semester.

The device they created, PepGuard, adds a microcontroller and a serial JPEG camera to a canister of pepper spray. When the button on top is pressed, the microcontroller flashes a LED, takes a picture with a camera, and sends that picture to a phone over a Bluetooth connection.

PepGuard is always connected to the user’s phone via Bluetooth, and this allows for some interesting possibilities. With their Android app, the team can set up the phone to call emergency services when the device is activated.

You can check out the demo of the device after the break, or read the team’s report here.

Filed under: security hacks

This guide will show you how to bind books by hand. The process from start to finish isn’t very difficult as long as you follow each step along the way. The final product looks great, and we can’t think of a better gift… as long as you have something meaningful on the pages.

We never really thought about the direction of the fibers in a sheet of paper, but that’s the first thing you’ll have to take into consideration here. You want the fibers running up and down when the book is in a bookcase. Next the sheets are organized into stacks of four, then folded in half forming eight pages. After stacking these packets together a series of lines are marked on the folded side. Holes are then punched from the inside at each mark using a sturdy needle. This is where the stitching for the binding will happen. Bands are added using coarse linen thread. After stitching these in place and knotting, glue is added and finally a piece of cloth is adhered to the binding and a portion of each inside cover. From there it’s onto fabricating the cover before pressing the finished project as seen above. What a piece of work!

[via Reddit]

Filed under: misc hacks

A while back we saw the MintEye CAPTCHA system  - an ‘are you human’ test that asks you to move a slider until an image is de-swirled and de-blurred – cracked wide open by exploiting the accessibility option. Later, and in a clever bit of image processing, the MintEye CAPTCHA was broken yet again by coming up with an algorithm to detect if an image is de-swirled and de-blurred.

It appears we’re not done with the MintEye CAPTCHA yet (Russian, translation). Now the MintEye CAPTCHA can be broken without any image processing or text-to-speech libraries. With 31 lines of Java, you too can crack MintEye wide open.

The idea behind the hack comes from the fact that blurred images will be much smaller than their non-blurred counterpart. This makes sense; the less detail in an image, the smaller the file size can be. Well, all the pictures MintEye delivers to your computer – 30 of them, one for each step of swirl and blurring – are the same size, meaning the ‘wrong answer’ images are padded with zeros at the end of the file.

There’s a 31 line program on the build page that shows how to look at thirty MintEye images and find the image with the fewest zeros at the end of the file. This is, by the way, the correct answer for the MintEye CAPTCHA, and has a reproducibility of 100%.

So, does anyone know if MintEye is a publicly traded company? Also, how exactly do you short a stock?

Filed under: security hacks

Looking to build your own instrument out of plumbing and tape? [Scott] made his own set of Membrane Bagpipes out of PVC pipes, a plastic bag, and duct tape.

Bagpipes are made out of a few parts. The drones are pipes that are tuned to play a single note. They are tuned by the fixed length of the pipe. The chanter is a tube with finger holes. This lets you play various notes depending on which holes you cover. The blowpipe is used to fill the bag with air that will pass through the membranes on the drones and chanter. Finally, there’s the bag which stores air.

[Scott]‘s build uses PVC for the drones and chanter. The membranes are made out of cut up bits of plastic bags. Some crafty duct tape work makes up the bag, and seals it on to the various parts. A check valve is used to stop warm, duct tape flavoured air from blowing back into your mouth.

It’s pretty amazing what people can do with a few rolls of duct tape. The pipes aren’t exactly in tune, but they certainly work. Check out a video of them in action after the break.

Filed under: musical hacks

[Samir] dabbles in hobby electronics and decided to put his skills to the test by building this portable gaming console (Note: this site uses an HTTPS address which cannot be used through Google Tranlator. It does work for the Chrome browser translator). The image above is a screenshot from his Breakout-style game. The paddle at the bottom is controlled with the touchscreen. You move it back and forth to keep the ball from traveling past the bottom edge (it bounces off of the red borders on the sides and top).

The main PCB is larger than the 3.2″ LCD footprint, but [Samir] made sure to include a lot of peripherals to make up for it. The board sports a Parallax Propeller chip to run the games. It interfaces with the SSD1289 screen (this is a cheap and popular choice) but that really eats up a lot of the IO pins. To control the game the touchscreen can be used as we’ve already mentioned. But there are two other options as well. There is an expansion port which uses a shift register (74HC165) to serialize the input. For prototyping this allowed [Samir] to use an Atari joystick. He also rolled a Bluetooth adapter into the project which we would love to see working with a Wii remote. Rounding out the peripherals are an SD card slot, audio jack for sound, and an RTC chip for keeping time.

There are several videos included in the post linked above. After the break we’ve embedded the game-play demo from which this screenshot was taken.

Filed under: Microcontrollers

I wrote about GoFundMe back in December. The low-bar-to-entry crowdfunding site caters to users looking to raise funds for "life needs" like medical expenses and weddings, but now they want to expand their service to makers by offering a new "all or nothing" funding feature and the same easy terms. The company has partnered with MAKE to get the word out and today they're announcing a potentially lucrative contest for makers with bright ideas.

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This telepresence upgrade lets an employee take part in the office from more than four thousand kilometers away. It’s an upgrade of their previous setup which used a laptop on a rotating platform to add a bit of control to the video conferencing experience. But all that original version could do was swivel, this one lets you drive your virtual self around for fifteen hours between battery charges.

The real work is in the base of the robot, as the audio and video are handled by a tablet independently from the locomotion. The team spent about four hundred bucks to throw the thing together. It starts with a hunk of plywood. Two 3A motors were mated with lawnmower wheels for the front of the bot. Dragging under the back of the base are a couple of casters that make it possible to turn without skidding. A motor shield and a WiFi shield for the Arduino make it possible to control the thing over the Internet. They even added some functionality on the client side to use a PlayStation 3 controller. Check out the completed machine in the clip after the break.

Filed under: news

We're back after a short hiatus -- hope your 2013 is starting out mathematically auspiciously. (And lest the last two digits of the year worry you, note that typically, from a mathematical point of view, the multiplicative factors of a number are more significant than addends that produce the number.

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We get asked this question all the time. Implicit is usually a hint of "I don't get it. What's the big deal?" The superficial answer seems absurd. "Making is the act of creating something." It's been around forever. It's not new. And yet I'm excited about it. There's a movement about it. There's talk of it changing the world. Why is this so?

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If you have dreams of competing with Kabletown, this project from Open Electronics might just give you your start. Their DTT transmitter circuit will let you transmit up to four channels of video and audio to television sets with digital tuners. To achieve this, there are four encoders on board [...]

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When we read “smaller paddles” we immediately thought of the physical controllers that you hold in your hands. But this hack alters the size of the virtual Pong paddles displayed on the TV screen.

We remember quite well the episode of That 70′s Show where Red and Kelso take apart their Pong machine to hack it. The video after the break which [Blues Image] put together shuffles scenes from that episode in with images of his hack. The characters are adamant that the game is too easy and reducing the size of the virtual paddles is the only thing that will make it fun again. After building his own hardware from the original schematics, [Blue Image] figured this challenge was worth a try.

His solution is in the form of two man-in-the-middle boards which insert a way to reroute the pins without altering the main board. One of the chips is used to draw the paddles, the other checks for collisions with the ball. By changing the pin-out the paddles are reduced from fifteen pixels down to seven.

[via Reddit]

Filed under: classic hacks

Welcome to the sixtieth installment of Your Comments. Here are our favorites from the past week, from Makezine, our Facebook page, Google+ Community, and Twitter.

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