Monitor Keg Volume, CO2, And Temp

December 14, 2009 by Mike Szczys 13 Comments

[Jean-Michel] tipped us off about his beer keg monitoring setup. It can tell you how much beer is left in each keg, how much carbon dioxide remains in the canister, and it can monitor and regulate temperature.

An Arduino mega is the brain of the system. A shield was built to interface force sensors, measuring the weight of the keg to estimate how much beer remains. Analog temperature sensors allow for temperature monitoring and control of the compressor for regulation. Information can be displayed on a graphic LCD or a computer via XBee wireless communications.

This is along the lines of the SparkFun kegerator but we like the added functionality. Does this need to Twitter? Probably not but if you want that, it’s only a bit of a software hack away.

GSM Enabled Security Door

November 28, 2009 by Mike Szczys 14 Comments

The security door at the front of [Oliver’s] building uses an intercom system to let in guests remotely. Each unit has an intercom handset with a button that unlocks the door. [Oliver] wanted a way to enter without carrying any extra items so he built a system to unlock the door with his cell phone.

He patched into the intercom and attached a GSM module. The module runs python so he wrote a script that will monitor the entryway buzzer, then wait for an approved cell phone connection to unlock it. He went through a couple of different iterations for the final project. The first attempt used XBee modules to communicate between the intercom handset and the GSM module. For the final version, he snaked cable through his wall using rare-earth magnets (creative!) in order to forgo the use of a battery in the handset.

Who doesn’t carry a cell phone with them? Because of this, the use of GSM modules in automation is a trend we think will continue to gain popularity.

Urban Defender: Location Aware Game

November 7, 2009 by Jakob Griffith 30 Comments

[youtube http://www.youtube.com/watch?v=zrAFYava258&feature=player_embedded%5D

What do gangs, territories, cities, and glowing blue balls have in common? No, not that one drunken night you can’t seem to remember, rather a new location aware game called Urban Defender.

The concept behind the game is simple. A player hold a ball that knows its current location and can notify you if needed via LEDs and a speaker of changes in its environment. He or she then runs around the city until the ball tells them of an unclaimed or enemy territory. Bounce the ball against a building and that territory is now claimed.

The ball itself is a prototype combination of an Arduino, Accelerometer, vibration motor, LEDs, XBee, batteries, and wire all packed inside of an industrial rubber gym ball. Unfortunately after testing the Urban Defender team found the GPS and a few other components would need to be kept outside of the ball and on the player.

Finally, a project that warrants the use of an Arduino. Anyone up for a game?

Cheap Wireless For Microcontrollers

August 30, 2009 by Jakob Griffith 44 Comments

hr_RF_circuit

Everybody loves microcontrollers, including the Arduino, allowing you to create whatever you imagine. That is unless you want to hack together something wireless. Originally you had to rely on the expensive XBee protocol or other wireless options, but no longer. Hobby Robotics found an extremely cheap transmitter and receiver and wrote a quick guide for wiring them up to an Arduino. Now your wireless projects can come to life, as long as you are within 500 feet and don’t mind 2400bps; minor trade offs compared to the gains of wireless freedom. Final note: You aren’t limited to Arduino, we would love to see someone modify this to work with a PIC or other microcontroller.

WiFi Spectrum Analyzer

August 18, 2009 by Caleb Kraft 18 Comments

ez430 (Custom)

[Tim] noticed a 2.4Ghz WiFi spectrum analyzer on thinkgeek a while ago and got curious. He knew that the spectrum analyzers with which he was familiar were giant expensive units, so he got curious what this little dongle was. It turns out, it really wasn’t much at all. Just a simple wireless receiver. He decided that rather than spending the $399 for one, he would toss one together using an Xbee. His total cost ended up at roughly $50 for basically the same unit. While he doesn’t give a schematic, you can download his source code on the site.

Sewer Clog Alert System

July 27, 2009 by Zach Banks 34 Comments

xbee

[miketysklar] noticed that a local business was having trouble with their sewage lines. People kept flushing tampons down toilets and it ended up clogging the pump. They had already installed a set of lights and horns to go off when it clogged, but they were hoping for SMS capability so they would know wherever they were. The new system piggybacks off the flashing lights by powering an XBee when they are activated. The signal it sends is recieved by another XBee attached to a computer running a python script. The script then sends a SMS via email to the poor fellow who has to fix it.

Related: Wireless Bootloading

Greenhouse Guard

July 24, 2009 by Zach Banks 15 Comments

pid

[Seth King] sent in his latest hack where he used an Arduino to regulate various aspects of a greenhouse. He has sensors for soil and air temperature as well as light and moisture. He built a custom circuit that uses relays to power fans, lights, and heaters. Using timers and the sensor data, the devices can be triggered to create the perfect environment for sprouts. He hopes to make the whole thing wireless by integrating XBees, but for now he ran a USB cord to his computer.

Related: Automatic grow light