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Hackaday Links: December 11, 2011

December 11, 2011 by 23 Comments

Drilling square holes

We’re still a bit baffled by the physics of this, but apparently it’s possible to drill a square hole with a round bit. This video shows square holes being milled using a cutter which is offset from the center of the bit. [Thanks Jordan]

LED Motorcycle headlight driven by mains

[William] found a way to use a big capacitor and bridge rectifier to run this H4 LED headlight bulb in a mains sconce lamp.

Electronic slide whistle

Here’s an electronic instrument that [Dorian] made. It uses a linear potentiometer and a button and works much like a slide whistle would.

Robot rocks out to Daft Punk

[Adrian] didn’t just make a robot arm out of CD cases and a mints tin. He built the arm, then made a music video featuring it.

More light-pipe sensor experiments

[Uwe] has been working on an input sensor using a flexible light tube. It is a similar idea to these optical flex sensors, but [Uwe] tried several variations like filling the tube with alcohol.

Hackaday Links: December 7, 2011

December 7, 2011 by 12 Comments

LED Neurons

[Alexandra Olivier] put up an art installation at Wellesley College that looks like a bunch of neurons built out of LEDs. The neurons are connected to a couple PIR sensors and ‘fire’ whenever movement is detected. The result is a lot like being inside a brain. Fitting, then, that the installation is called Social Synapses.

Last year’s big toy was always evil, though

Last year, [Andrew] had to fight the throngs of shoppers to get the must have toy of the season, a Zhu Zhu pet. Since these robotic hamster things have spent the last 11 months in the back of a closet, it seems reasonable to make them evil. They’re still not as evil as a demonic Furby….

So we call it a bifocal, right?

There’s an old photography trick for a really hacky macro setup – just turn the lens around. Well, what if you wanted automatic metering and flash control? Simple, just electrically reverse the lens. Bonus points for being able to use the lens regularly as well.

Control all the bands

Well here’s something cool: an all-in-one USB 315mhz, 433mhz, and 868mhz transceiver. What can you do with it? Well, [codeninja] can control the outdoor lights for two of his neighbors, open gates and doors, crash his weather station, and just about anything else in those bands. It’s pretty much like war driving for important stuff nobody cares about.

So this is our favorite holiday now

There’s a Dutch tradition to play Sinterklaas and make someone a present. [Jenor] decided to build an antique-looking DC voltmeter with a pair of vacuum tubes. The tubes don’t work anymore, but the heaters still provide a nice warm glow. It’s a bit large to be regularly used as a piece of test equipment, but it really does look awesome. Very steampunkey, and it’s the though that counts anyway.

Hackaday Links: December 3, 2011

December 3, 2011 by 35 Comments

Honey, would you like some cheese? WHIRRRRRRRRR

[The Timmy] broke his manual cheese grater. It would be a waste to throw away a perfectly functional tool that’s only missing a handle, so he kicked it up a notch with a cordless drill. Now [Tim], “can grate with incredible speed and power for even the toughest of cheeses.” Anyone have a broken pepper mill?

The most adorable oscilloscope

We’re not much for plugging products, but this scope is really cool. It’s designed to fit on a breadboard and is smaller than some ICs we’ve seen (68000, so yes, it is). We’re wondering why there hasn’t been a homebrew version of this yet.

Now do an R/C castle

Here’s a minifig-sized R/C LEGO car made by [brickmodder]. It has a custom drive train and steering mechanism that uses the smallest servos [brickmodder] could find. How about an R/C pirate ship next?

It’s probably an ad for something

Here’s some sort of code thing that asks the question, “Can you crack it?” Apparently, it’s for UK cryptanalyst recruiting. You won’t get a 00-designation, but woo Bletchley Park.

Inverting an inverter

[Manfred] is putting an alternative energy setup on his land. Of course he needed an inverter to charge his batteries, so he went with a highly regarded (high price) box. What he got was anything but. You’re going to need at least ten minutes to go through this hilariously sad teardown of a high quality Taiwanese inverter. Oh, [Manfred] is awesome. Just look at his microhydro plant.

Hackaday Links: November 24, 2011

November 24, 2011 by 9 Comments

Finally an Arduino shield that does nothing

The folks at Evil Mad Scientist labs have finally created the Googly Eye Shield for Arduinos. With it’s pass-through .100 headers, it adds googly eyes to your Arduino projects. Of course, instead of in addition to the googly eyes you could add a breadboard, making it somewhat useful. A million fake internet points goes to the first person to implement Xeyes on this thing.

Phat beats from kids toys

[Ville] couldn’t afford an Akai MPC for laying down some beats. Wanting a real tactile interface, he hacked this kid’s toy. It’s just an RCA cable attached to the tiny chip inside the toy. The new line out goes to his mixers where he does some pretty impressive stuff.

Mona Lisa is Vigo the Carpathian

What did we just say about real-life Xeyes? [Geert] just made a print of the Mona Lisa follow you around the room with her eyes (Dutch, translation). The build is a pair of servos and a DIY motion capture app running on a laptop. Now we need to find a print of Vigo…

Quantifying heat sink efficiencies

[Mike] is an experimenter at heart. He was wondering about the efficiency of small, clip-on heat sinks versus the ones we use to defrost frozen food. The results are exactly as you would expect, but he did find something interesting – his experimental technique didn’t find much of a difference between thermal paste/grease/pads and no thermally conductive material.

Mini-fig sized R/C LEGO car

The guys at Brickmodder.net took a car from a LEGO set and made it remote control. The drive train and steering both use servos controlled by the smallest 3-channel receiver they could find.

Hackaday Links: November 10, 2011

November 10, 2011 by 11 Comments

Experimentations with haptics

[Chris] sent in two videos (1, 2) documenting his experiments with haptic feedback. He’s recording the position of a DC motor and can either play it back or send it to another motor. It’s very similar to the kissing robot we saw earlier this year, but we’re not making any judgments.

Mobile Emergency Repeater go bag

[Nick], a.k.a. [KF5JAK] sent in a few pics of his emergency/disaster relief amateur radio go bag. With a 3G connection via a cell phone, the MER can be used with EchoLink.

Launchpad MIDI booster pack

Earlier this month we lamented the dearth of add-ons for the TI Launchpad. The folks on the 43oh forums just came out with a MIDI booster pack. Time to dust off that old Radio Shack keyboard, we guess.

Macro photography with OH GOD WHARGARBL

You know camera lenses work both ways, right? [Karl] has been experimenting with this very idea by mounting a camera lens backwards and running a few wires so it’s electrically connected as well. Check out an example shot.

Keeping tabs on your kids’ homework

[Janis] doesn’t live with his kids but he wanted to keep track of their homework. He set up a document scanner that sends those worksheets straight to his email inbox. All he has to do is annotate them and send them back. This guy’s doing it right.

Hackaday Links: November 6th, 2011

November 6, 2011 by 16 Comments

Build details for Raspberry Pi prototype

With the launch of Raspberry Pi approaching the development team released the details about the prototypes from about five years ago. The board was originally based on an ATmega644 and built on some perfboard.

‘Zero Energy Device’ challenge

We call BS on the title of this one, but the goal of finding devices that don’t use disposable energy sources is a good thing in our book. For instance, can we get more stuff that uses long-life capacitors instead of batteries?

Command adhesive for mounting bulletin boards, etc.

This seems like a no-brainer, but we’ve been using nails to mount bulletin boards and white boards for year. The problem is, when you stick a push-pin in one side, the other side pops off of the nail. [Zhanx] is using adhesive from 3M Command Hooks to keep his stuck to the wall.

Servo-driven gripping hand

[Navic] has been hard at work on this robot hand. There’s few details but he shows it can grip objects under one pound and he’s been taking amperage measurement during testing.

Emergency cellphone charging

It might not have been an emergency this time, but [Chris] did figure out a way to charge his cellphone after the snow storm in New England knocked out his power. He connected to lantern batteries to a 7805 regulator, then patched that into a USB hub to get his phone connected. Not bad in a pinch!

Hackaday Links: October 28th, 2011

October 28, 2011 by 24 Comments

An accidental radial engine

Hack A Day’s very own [Jeremy Cook] was trying to figure out how to push four ‘arms’ out one at a time. What he came up with is a very nice model of a radial engine. Everything was cut on a CNC router and a motor from an air freshener provides the power.

Using a candle to produce light

[Chris] sent in his Candela Amplifier. It’s a Pentium 4 heat sink with a very bright Cree Xlamp LED attached to the base. A bunch of Peltier thermoelectric units are attached to the underside of the heat sink. Put the whole thing on top of a candle, and you can light a room. With a candle. Oh, he’s selling these, by the way.

Objectification and video games?!

We really feel sorry for our lady readers. Guys have so many choices for Halloween costumes, but just about every costume available for women can be reduced to, “Sexy [noun].” Whelp, here’s the Sexy Game Boy, just in time for Halloween. [kazmataz] gets a few bonus points because she went with the DMG-01. It’s better than Sexy Chewbacca, so she’s got that going.

Prototypable 32-bit uCs

[Ng Yong Han] wrote in to tell us about some newish 32-bit PICs that are floating around. The datasheet for the PIC32MX1xx/2xx chips is pretty interesting – USB support and an audio and graphics interface. Oh, they come in PDIPs for ease of prototyping as well. We haven’t seen much from the PIC microcontroller faction recently (Atmel is winning the holy war, it seems). Anybody feel like building something with these?

Makerbot dual extruder


[Lomo] at TU-Berlin is taking a class in rapid prototyping. He built a second print head for his department’s Makerbot Cupcake with a few other students. The result are pretty impressive, although from what we’ve seen, it’s generating the G-code that’s a pain in the butt.