Control an Arduino from Android over Bluetooth

Whether you’d like to do some real-time logging of data, or just want to control a project with your Android phone, [Thomas]’s Arduino-Android Bluetooth connection instructable is sure to be useful

[Thomas]’ build uses the very inexpensive JY-MCU Bluetooth module that’s available on eBay or dealextreme. This Bluetooth module ties directly into the Tx and Rx lines of the Arduino so a wireless serial connection between an Android device can be established. On the Android side of the build, Python for Android and the Scripting Layer for Android allow for reading wireless sensor data over Bluetooth.

While connecting an Android device to an Arduino is also possible with an IOIO  or an Android Open Accessory dev kit, we haven’t seen much (barring this) about controlling or reading simple electronics with Android over Bluetooth. Sometimes you just don’t need an awesome dev board to bodge up a simple project, so we hope [Thomas]’s very nice instructable will help get a few more builds off the ground.

Becoming the YouTube loading animation

Whether you’re used to dropped wifi connections, or your housemates are using up all the bandwidth for streaming, we’ve all see the spinning octet of disks that is the YouTube loading animation. [technocrat] thought it would be a great idea to actually become YouTube and set out on designing a physical manifestation of the loading animation.

[technocrat] used eight ping-pong balls as the main structure of the build. After drilling each ping-pong ball and gluing white LEDs in, the only thing left was to connect everything up to an Arduino. The code loops through each LED and provides the ‘light trail’ animation YouTube has burned into our memory.

To complete the build, [technocrat] attached his physical loading animation to a black t-shirt emblazoned with the YouTube logo to make everything more understandable. While it may not be as colorful as the beachball of death or as conceptual as the Windows ‘spinning hourglass’, we’re really liking this build. Check out the video after the break.

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Wireless solar water heater controller ensures hot water every time

water-heater-controller

[Peter Sobey] had a solar hot water heater installed in his home, which worked great until he relocated his kitchen to a neighboring room. Now a good bit further from the tank, the hot water reaching his sink was tepid at best due to the increased distance and temperature limiting mixer valve in the new heater.

He installed a salvaged solar panel and water tank solely for use in his kitchen, but as the panel was located above the tank, he had to find a way to actively monitor and control the water temperature. His pump and valve system was originally driven with an off the shelf PICAXE-based controller, but he eventually got the urge to add a wireless display and control panel to the mix.

A pair of Arduino Nanos run the show now, one of which resides in the pump controller box, while the other is used in the temperature display box in his kitchen. He uses a set of Bluetooth modules to link the Arduinos together, relaying temperature data and allowing him to send the pump controller manual commands if needed.

He says the system works a treat, and he’s much happier with his homebrew controller than the one he used originally.

Antique phone provides a soundtrack perfect for restoring old cars

crank-phone-music

[Simon] is in the middle of restoring/building himself an Austin 7 Special out in his garage, and like most tinkerers, found that music helps to move the process along. He happened to have an old Bakelite generator phone out in the garage as well, and figured that he might as well have it do something other than simply hang on the wall.

Playing music from the 1930 seemed like a fitting enough task, so he picked up an Adafruit Waveshield and spent some time wiring it up to the old telephone. His new radio works simply enough, piping .wav files through the handset, provided someone has cranked the phone’s generator recently.

While cranking the generator is required to play music, the Arduino is actually powered off a pair of AA batteries. The cranking is all cosmetic, but he did program the Arduino to slow the music down every once in awhile, requiring that the generator be turned to get things back up to speed.

It really is a neat way to repurpose the old phone, and we like the fact that [Simon] did not gut it to put this project together.

Continue reading to see a short video of his new music player in action.

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R2R ladder connects multiple buttons to one ADC pin

If you’ve run out of I/O pins on a project and need a way to add user input you can find a slew of port expanders that work with various communications protocols like I2C and 1-Wire. But if you just want to add in some buttons without reaching for an extra IC you’ll love this hack. [John Boxall] shows how to add four buttons using one ADC pin.

The concept is nothing new. The buttons make up an R2R resistive ladder. When one of them is pressed, it completes the circuit for a voltage divider. The results are measured by the analog-to-digital converter of an IC to tell which button was pressed. The difficult part is calculating the resistor values. [John] is using eight resistors made up of just two different values. Every button and every combination of buttons has a unique voltage result which can be discerned by the chip. He even made a truth table so you don’t have to.

The example circuit seen in the video after the break uses an Arduino. But this concept is directly applicable to any microcontroller. And it should be quite easy to use an ADC interrupt to drive all of the button-read events. [Read more…]

Minestation – An external weather display for your Minecraft world

minestation

If you’re a big Minecraft fan, the folks at [radikaldesign] have something that might be of interest to you. (Translation) Inspired by some of their Minecraft-loving friends, they have developed Minestation – a weather station for your Minecraft game.

The concept is simple. Here in the real world we have the ability to look out the window and see what it is like outside, but many of us turn to digital weather stations, the Weather Channel, or the local news to get the real scoop. They decided that the world of Minecraft should be no different, so they constructed an Arduino shield that allows players to see weather conditions as they play.

The shield contains a Nokia 6100 LCD screen which displays all sorts of useful information. It features a clock and calendar that reflect in-game time, making it easy to know when night is going to fall. It also continually displays the player’s coordinates as well as what the weather looks like in that region. Having this information at hand when you’ve been slogging away in the mines (losing track of time and weather) seems like it could be pretty useful at times.

You can buy one of the devices at Minestation.me, but the design is completely open, so you can easily construct one of your own without too much hassle.

Continue reading to see a video of the Minestation in action.

[Via HackedGadgets]

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