Replacement Refrigerator Controller

[Michael] got his hands on a refrigerator that he intended to store beer in but found that it ran constantly. Instead of buying a new thermostat he and his friend [Doug] set out to build an Arduino-based controller for the fridge.

The finished project will switch 240v so they’ve used a transformer to power the logic circuitry and a solid state relay to handle the load switching, with a Dallas 1820 for temperature data. Because the Arduino offers more capabilities than the average thermostat hack they also decided to tap into its potential by adding an Ethernet shield. We see the Arduino as a prototyping device and so do these folks. Once the bugs in their first PCB prototype are worked out the circuit will use the ATmega328 and do away with the Arduino.

[via @littlebirdceo]

You’re Not Seeing Double: RGB Christmas Trees

[youtube=http://www.youtube.com/watch?v=GAt6A98lXQw]

[mrpackethead], created this monster of a tree.  As shown in the video, it’s capable of showing animations, patterns, and potentially video. The 6m tall creation is studded with 2000 waterproof RGB LED modules. Software for the tree was written in Apple’s own Quartz Composer and integrated into Madrix, a piece of software designed with the purpose of controlling LEDs. The 600W system is 100% Arduino-free and costs less than the equivalent of 0.04USD per hour to run in New Zealand.

[Geoist] opted for the Arduino way to rig up his own smaller RGB Christmas tree. Finding a slightly kitschy fiber-optic model in his local department store, [Geoist] was eager to harness its colour-changing powers. Upon opening it up, it was discovered that it was controlled by nothing more than a light bulb and a spinning disk of coloured light filters. [Geoist] gutted the setup in favour of a breadboard with 3 RGB lights hooked up to an Arduino. The sketch for it is available on his site.

Spreading Christmas Cheer W/ Auto Parts

The folks over at [Soup], a British marketing agency, thought up this cool project. It’s a set of handbells hooked up to an Arduino, actuated by central locking motors found in car doors. By the look of some pictures, there was also a Lego version. Songs written by users (through the online interface) are placed in the que of a server. Once it’s time for the song to be played, serproxy sends the Arduino an appropriate set of commands for ringing the bells in sequence. All of this happens in the [Soup] office while it is streaming live through a webcam.

We think that this is definitely a great way to use surplus auto parts. After all, not everyone can build helicopters.

It seems as though the bells are down for the moment, or the employees got a bit annoyed at hearing them constantly ring.

Laser Harp

[Jared] had a bunch of lasers left over from a previous project that he put to use by producing this laser harp. The look of it reminds us of a very small Koto or perhaps an Autoharp (although the chords can’t be changed on this model).

We’re so glad that [Jared] spent the time to produce such a fine looking body for the instrument. The strings that would traditionally produce the sound on a harp have been replaced with laser diodes shining at Cadmium Sulfide photo resistors. When a beam of light is broken, an Arduino detects the change via the CdS cell and plays a sound through an Altec Lansing speaker inside of the case.

Unfortunately there’s no video available but we’re pretty sure it makes a “pew-pew” sound. There is a link to download the source code but it points to the overview page instead of downloadable code. From the fritzing diagram the CdS cells are part of a voltage divider which provides digital logic to the Arduino. That should be pretty easy to replicate even without seeing [Jared’s] code and we’re sure you can source other Arduino instrument projects for tips on wave shield or midi functionality.

[Thanks The Cheap Vegetable Gardener]

Open Source Artillery

[youtube=http://www.youtube.com/watch?v=zPm84nxa2dk]

Thanks to [Josh, Kyle, and Mike], it is now possible to wage (Nerf) war with an Arduino. The turret designed around it is capable of shooting 6 foam projectiles in close succession, between reloads. The faux weapon interfaces with a computer through the Arduino’s onboard serial link (via USB). Software on the PC sends commands to the Arduino, which then executes functions, such as panning, tilting, firing, and rotating the cylinder. The power for the firing itself comes from a 5 gal, 80 psi air compressor. The Java software on the host PC also does smarter things, like show streaming video from the turret’s webcam and even performs basic object tracking (with mixed success). All the code for building the brute is available on [Josh’s] website.

Atmolight Clone Of An Ambilight Clone

[youtube http://www.youtube.com/watch?v=i4JnrAwullI&feature=player_embedded%5D

[Fun3] wasn’t satisfied with current methods for duplicating Philips Ambilight. He wanted a completely plug and play solution without soldering so he could expand upon it in the future. This meant Arduino, ShiftBright, and (it pains us to say this) pre-made cables. Some of you are cringing at the thought of no real ‘work’ being necessary, but remember, now this is much easier for your “I can’t change the VCRs clock” aunt to set up and enjoy. Plus it’s quick, easy, and most importantly – clean, something a lot of hackers have a problem with.

Arduino Now Controlling – The Crop Harvest?

[youtube=http://www.youtube.com/watch?v=LDzHwy28kng]

We’ve seen the Arduino board in charge of some pretty unique tasks in the past. Harvesting locally grown soybeans was not one of them.

[Lance] rigged this beast up in order to automate the monotonous task of driving up and down the vast soybean fields of Iowa. The 15 ton farm combine’s hydraulic steering pump is at the mercy of a team of gadgets, including a GPS, Windows 7 PC, and the omnipresent Duemilanove (which acts as the output card, connecting the PC to the pump). So far, it is reported to be doing a great job, straying only about an inch and a half from its desired, GPS-programmed, path. Even if the Arduino decides to go totally berserk and drive the combine off course, speeding around at 5mph makes it pretty avoidable. A supervisor is also in the cabin at all times, looking out for errors. [Lance] eventually hopes to offload all steering-related calculations to the ATmega328P onboard.

Commenters are welcome to share heavier-duty uses for the Arduino (if they exist).