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?
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.
[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.
[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.
[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.
Reader, [Andres Leon], has two adorable cats with very specific dietary needs. Instead of altering his schedule, he donned his hacking hat and designed a very solid cat food dispenser. The dispenser consists of a rotating drum with a slot in it and a PVC pipe Y-fitting to distribute the food evenly. The brains of the machine is an Arduino Deumillanove and an XBee module. The unit can be controlled by a web interface or it can run completely standalone. [Andres] ran into a problem where the drum’s resistance to turning varied based on how much food was inside. He solved this with a clever laser position indicator. A piece of plywood is lined up with the slot at the top so that whenever the slot is facing up it keeps the laser from shining on a photoresistor. The cats were afraid of the servo noise at first, but now they run to their bowls whenever they hear it.
Liquidware has put together an interesting kit called the WiNet. It has a battery powered touchscreen controlled by an Arduino. Using an XBee shield, it can send commands to a paired XBee and Arduino attached to a computer. The computer can also update the touchscreen display. This is demoed in the video below. It’s a unique interface, but the TouchShield alone costs $174 so we’re guessing you’re going to be pretty damn confident in your project before you go this route.
The team behind the the Tweet-a-Watt/Wattcher just won first prize at the Greener Gadgets design competition. The device is a hacked Kill A Watt that transmits power consumption using an XBee. After checking out DVICE’s preview of the competitors yesterday, we’re happy to see a prototype win instead of just a concept sketch.
Tired of having to physically connect to your microprocessor to upload new code? Just do it over a wireless connection. [Nathan] takes us through the process of setting up a wireless bootloader for the ATmega168. He is using the XBee base and remote modules for the wireless communication. While people have been doing wireless bootloading with the Arduino already, [Nathan] found that it was common for them to have timeout issues. His remedy was to make his own custom one that is much faster. He’s asking for help though. At this point it is tested and working, but he needs someone with more programming knowledge to help him make it “drop-in” compatible with the Arduino IDE.
You probably saw [Phillip Torrone] and [Limor Fried]’s twittering Kill A Watt earlier this week. It was an entry in the Core77/Greener Gadgets Design Competition. We saw a little bit about how it was assembled, but now they’ve posted a full guide to assembling the hardware. Each Kill A Watt gets an XBee radio that transmits back to a receiver that logs the power usage. The difficult part when putting this design together was the XBee required 50mA when transmitting. This is well above the Kill A Watt’s internal power supply. They remedied this by adding a 10,000uF supercap to act as a rechargeable battery. The daily twittering is just a side-effect of the project. The Kill A Watts transmit every 2 seconds, so you’ll get a very accurate report of your power usage. This is a great project for renters who can’t permanently modify their power infrastructure. Each Kill A Watt can support quite a few appliances since they’re rated for 15A, ~1800W.
