A simple project to get you started with the Android ADK

simple-adk-exercise

If you just got your hands on a shiny new Android phone and are looking for a fun project to try out, you might want to check out this simple Arduino exercise that [Mike Mitchel] put together. Everyone needs a starting off point for hacking, and [Mike] thought that combining and Arduino and Android handset together for the purpose of temperature sensing and light metering would be a great place to begin.

The prerequisites for this project are a bit beyond a simple breadboard and a few ICs, requiring an $80 Android ADK board to go along with your phone and Arduino. If your focus is going to be on interfacing your phone with microcontrollers however, it’s purchase you’ll make sooner than later anyhow.

The setup is pretty simple as you might expect. A photocell and TMP36 temperature sensor are connected to the Arduino, then with a bit of code and USB host magic, the Android app shows the temp and amount ambient light present in the room.

[Mike] has made all of his easy to read and well commented code available online, so be sure to check it out if you have been thinking about (but putting off) playing around with the Android ADK.

Arduino aquarium lights

[Kalle Hyvönen] just finished building his own aquarium lights. He used four powerful soft-white LEDs, mounting them on a pair of heat sinks to keep things cool. Now he could have just connected them to the power supply and plugged it into the wall, but instead he included is own controller. An Arduino drives the switch-mode power supply, offering dimming thanks to PWM, and the ability to automatically switch the light on and off using an RTC chip with a battery backup. The sketch includes the ability to alter the lighting schedule and other variables by sending serial commands through a USB connection. This protocol is detailed with comments in his sketch.

We’ve seen a lot of interesting aquarium light projects. This one that uses heat from the LEDs to warm the water is one of our favorites. Others are full of features like this version that includes a moonlight mode. But Arduino enthusiasts don’t have to look far to find offerings like this PAR meter build, or this aquarium light controller library which can be recreated using the ubiquitous controller board.

Rotary phone-light-amp could be filed under bizarre

[Samimy's] latest project is a little strange, but one man’s weird is another man’s wonderful so we’re not about to start criticizing his work. Nope, we’re here to praise the fact that his rotary phone turned reading light and audio amp is very well constructed.

He started by removing the phone housing. Those old enough to have used one of these devices will remember their bulk, and there’s a lot of unused space in both the handset and body housing. [Samimy] started by removing the speaker and microphone from the handset, and drilling a ring of holes to receive white LEDs. The circuit was wired so that lifting the handset turns on the lights.

But he didn’t stop there. A set of speakers and the audio amplifier circuitry from an old tape deck are also hiding inside the base of the phone. If you look closely in the image above you can see that he’s connected his cellphone and is listening to some tunes through the antique hardware. Take a gander at the video after the break to see construction and use of the project.

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Sensor array tries to outdo the other guys

The team over at the Louisville Hackerspace LVL1 is not going to be outdone when it comes to collecting environmental data. They put together this Frankenstein of sensor boards that lets you collect a heap of data showing what is going on around it.

At the center-left a small Arduino clone is responsible for collecting the data. Data storage is not talked about on their write-up, but if that’s an ATmega328 chip you should be able to work out an easy way to store data on the 1k of internal EEPROM. If that’s not enough, there is an I2C bus included on the board making it easy to add a compatible EEPROM.

The sensor on the bottom left should look familiar. It’s a DHT11 temperature and humidity sensor we’ve seen popping up in projects lately. But wait, there’s also a TMP102 temperature sensor; but that’s not the end of it. A BMP085 pressure sensor also includes a third temperature sensing option. Want to see when the lights go on in the room? There’s a CdS sensor and a TSL230R Lux sensor for that. An op-amp circuit can measure the sound level in the room via one of the Arduino’s ADC pins. And finally, an RTC board is used for time stamping the data.

Obviously this is overkill, and we’re sure it’s meant as a test platform for various sensors. All of them have been mounted on the protoboard and wired up using the point-to-point soldering method.

Lighted fan pull saves you from flailing around in the dark

lighted-fan-pull

Like many people, [yardleydobon] had a hard time locating his ceiling fan’s pull chain at night when his room is completely dark. Rather than continue to flail around blindly grasping for the chain, he decided to find a way to illuminate it instead.

He started off by disassembling a solar garden light, retaining the solar cell, photoresistor, and batteries. After paring down the electronics to the bare essentials, he mounted them inside a plastic battery storage case which he attached to the outside of the fan’s lamp. [yardleydobon] then ran a pair of wires from the electronics box down to end of the chain, where he added an LED and a translucent pull to diffuse the light.

He admits that it’s not the nicest looking modification around, but it does the job in a pinch. He has some ideas that he may put into play if he has the time to revise the design, and we bet that many of you do as well. If so, be sure to share them in the comments.

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Building a 1300 lumen bike light

[Brainiac27] isn’t going to let the absence of sun prevent him from biking. He has no trouble lighting his path with this 1300 Lumen bike light he built.

The light source is a 3-up star by Cree. It puts off a lot of light, but also generates quite a bit of heat which is the reason for that large heat sink. It is meant to be used with a CPU but works well for this purpose thanks to the adhesive thermal paste used to unite the two parts.

The mounting bracket is a custom job, bent from 1″ by 1/8″ aluminum bar. [Brainiac27] had some issues with length the first time he tried making it. For his second attempt he started with an overly long piece, made the bends from the center out, and only made cuts once the bends were all completed. The bracket makes it easy to mount to his bike, with the battery stored in a bike bottle and a remote switch (with attaches to the jack you can see on the project box above) hidden underneath one of the brake hoods.

The intensity of this light nearly doubles one of our other favorites.

Chicken light keeps up egg production

It turns out that as the days get shorter, chickens lay fewer eggs. But you can trick them into keep up production using artificial light. [Jpitz31] decided to build his own timed coop light to bridge the gap until the days of plentiful sunlight return.

He already had an LED camping light to use, but needed to find a way to power it and to switch it on and off on a schedule. He chose an ATmega328 for the latter, as he had a bunch of extras sitting around. As for power, there isn’t AC available where the coop is, so he opted for a 12V lead-acid battery with hopes of adding solar charging features in the future.

Switching is handled by a relay, with accurate time kept by a DS1307 real-time clock (it’s the red PCB seen above). Everything fits nicely on the board, and we have a couple of feature suggestions for future improvements. The linear regulators will eat up some extra power so moving to a switching regulator will help save juice. Also, it would be very easy to add a light sensor so that the light will only be on when the ambient light drops to a preset level. This way he won’t need to mess with the schedule as the length of the days change.