Posts with «android hacks» label

Making a Mega LED Desk

Few things beat a sturdy, home-built desk — especially when it’s jam-packed with over 1200 WS2812 LEDs.

[nolobot] and his bother struggled with setting up and squaring-off the t-slotted, extruded aluminium frame which makes up the desk. He recommends practicing with a smaller frame for anyone else attempting a similar build. The surface of the desk has a few inches between the polycarbonate top and the 1/4″ plywood painted black serving as the substrate for the LEDs. Those LEDs come in strip form but still required several hundred solders, and wiring headaches in an attempt to make future upgrades manageable. Dozens of support bolts with adjustable feet support the desk surface throughout. These all had to be individually adjusted and can be made out if you look closely at the demo videos.

An Arduino Mega controls the LEDs with the help of the FastLED library. Custom code was necessary because one of the major issues [nolobot] faced was the power draw. 1200 LEDs at 5V draw quite a bit of current, so the LEDs were coded to peak at about 50% brightness. The matrix was split into different banks, while also limiting the 40A PSU to only 15A.

Regarding the final product, all we can say is: woah.

Not a fan of putting this much work into a piece of furniture? There are also ultra-minimalist options at your disposal.

[via /r/arduino]


Filed under: Android Hacks, led hacks
Hack a Day 02 Mar 12:01

This Old Mouse Keeps Track of Filament Usage

Keeping track of your 3D-printer filament use can be both eye-opening and depressing. Knowing exactly how much material goes into a project can help you make build-versus-buy decisions, but it can also prove gut-wrenching when you see how much you just spent on that failed print. Stock filament counters aren’t always very accurate, but you can roll your own filament counter from an old mouse.

[Bin Sun]’s build is based around an old ball-type PS/2 mouse, the kind with the nice optical encoders. Mice of this vintage are getting harder to come by these days, but chances are you’ve got one lying around in a junk bin or can scrounge one up from a thrift store. Stripped down to its guts and held in place by a 3D-printed bracket, the roller that used to sense ball rotation bears on the filament on its way to the extruder. An Arduino keeps track of the pulses and totalizes the amount of filament used; the counter handily subtracts from the totals when the filament is retracted.

Simple, useful, and cheap — the very definition of a hack. And even if you don’t have a 3D-printer to keep track of, harvesting encoders from old mice is a nice trick to file away for a rainy day. Or you might prefer to just build your own encoders for your next project.


Filed under: 3d Printer hacks, Android Hacks

Raspberry Pi Radio Makes the Sweet Music of Bacteria

We’ve noticed a lot of musical groups are named after insects. Probably has something to do with the Beatles. (If you study that for a while you’ll spot the homophonic pun, and yes we know that the Crickets inspired the name.) There’s also Iron Butterfly, Adam Ant, and quite a few more. A recent art project by a Mexican team — Micro-ritmos — might inspire some musical groups to be named after bacteria.

The group used geobacter — a kind of bacteria found in soil — a Raspberry Pi, an Arduino, and a camera to build an interesting device. As it looks at the bacteria and uses SuperCollider to create music and lighting from the patterns. You can see a video of Micro-ritmos, below.

Music is a bit subjective, of course. We thought the music sounded a little oppressive. Not sure how much of that is the code and how much is the characteristics of the bacteria itself.

We’ve seen SuperCollider in a banana piano, before (these are popular because for most people bananas have appeal). We’ve also seen other natural processes generating sound like this project for presenting the sunset to the blind.


Filed under: Android Hacks, musical hacks, Raspberry Pi

Making a Gesture

When [krich] switched keyboards he lost his volume control. So he decided to hack one together out of an Arduino, an old floppy disc case, and a Hover Labs Hover board (not the Back to the Future kind). You can see the result in the videos below.

You’ll notice in the video that the device reads a “spin” motion to resemble a round volume control. The program sends simulated keyboard presses to the PC to control the audio. In the write-up, [krich] mentions it may be the first gesture-based volume control. However,we’ve done it before and so have others.

The Hoverboard does all the hard work, of course. It passes data to the Arduino via I2C. The PC side is handled by some Windows on screen display software, 3RVX.

Still, this one seems to work well with the Hover board. Hard to argue against anything that upcycles a floppy disc container.


Filed under: Android Hacks

Arduino Absentmindedly Blows Bubbles

If you ever wanted to make an occasion festive with bubbles, [Sandeep_UNO] may have the project for you. As you can see in the video below (and, yes, it should have the phone rotated and it doesn’t), his Arduino uses a servo motor to dip a bubble wand into soap solution and then pulls it in front of a fan. The entire operation repeats over and over again.

There’s not a lot of detail and no code that we could find, but honestly, if you know how to drive a servo motor from an Arduino, the rest is pretty easy to figure out. Look closely at the motion of the robot. What is often accomplished with a spinning wheel of bubble wands and a constant fan becomes much more interesting when applied intermittently. The lazy cadence is what you expect to see from human operation and that adds something to the effect.

We’ve seen faster bubble blowers, but they were not so simple. We’ve even looked at other bubble-blowing robots. If you want to find out more about servo motors in general, our own [Richard Bauguley] has what you need to know.


Filed under: Android Hacks
Hack a Day 31 Jul 00:01

Arduino RF Network Analyzer

What do you get when you combine a direct digital synthesis (DDS) chip, a power detector, and an Arduino? [Brett Killion] did make that combination and wound up with a practical network analyzer.

The project uses an Analog Devices AD9851 DDS chip clocked at 180 MHz which will output a sine wave at any frequency from 0 Hz and 72 MHz. A Butterworth low pass filter processes the DDS signal and then feeds a two-transistor amplifier. The circuit will output about 0dBm into 50 ohms. The power detector is an Analog Devices AD8307 along with a 50-ohm input load. There is no filtering on the power detector so it can measure from very low frequencies to 500MHz.

[Brett] uses a Python program to process the data from the Arduino. For example, here’s a plot of a 10 MHz crystal from the software:

If you want to know more about DDS, our own [Bil Herd] has you covered (see the video, below). We’ve also seen similar antenna analyzers that are about the same thing.


Filed under: Android Hacks, tool hacks

Ridiculously Automated Dorm Room

Take three NRF24L0+ radios, two Arduino Nanos, and a Raspberry Pi. Add a bored student and a dorm room at Rice University. What you get is the RRAD: Rice Ridiculously Automated Dorm. [Jordan Poles] built a modular system inspired by BRAD (the Berkeley Ridiculously Automated Dorm).

RRAD has three types of nodes:

  • Actuation nodes – Allows external actuators like relays or solenoids
  • Sensory nodes – Reports data from sensors (light, temperature, motion)
  • Hub nodes – Hosts control panel, records data, provides external data interfaces

The hub also allows [Jordan] to control things with his Android phone with Tasker. He has the Arduino and Raspberry Pi code on GitHub if you want to ridiculously automate something of your own. You’d probably want to adapt it to your dorm room, house, or RV, though.

[Jordan] continues to work on the project and promises to have voice recognition and other features, soon. We cover a lot of home automation projects including some others described as ridiculous. The video below shows BRAD, the inspiration for RRAD.


Filed under: Android Hacks, Arduino Hacks, home hacks, Raspberry Pi

Start Gaming Early with IKEA High (Score) Chair

If you want your kid to be really great at something, you have to start them out early. [Phil Tucker] must want his kid to be a video gamer pretty badly. [Phil’s] build starts with a $20 IKEA high chair. He likes these chairs because at that price point, tearing into them isn’t a big risk. What’s more is you can buy extra trays so you can use it as a modular project with different trays serving different purposes.

The chair has two joysticks and two buttons, looking suspiciously like a video game controller. The current incarnation (see video, below) uses an Arduino Uno to trigger an Akai MPC1000 synthesizer via the MIDI interface.

Of course, you could control other MIDI devices or even program the Arduino to do other things (like act as a game controller). We’ve seen lots of IKEA hacks, including a laser cutter, a camera slide, and even a printer (not a 3D printer, although we covered that, too).


Filed under: Android Hacks, musical hacks

Want a low-cost ARM platform? Grab a Prepaid Android Phone!

What would you pay for a 1.2Ghz dual-core ARM computer with 1GB RAM, 4GB onboard flash, 800×600 display, and 5 megapixel camera? Did we mention it also has WiFi, Bluetooth, and is a low power design, including a lithium battery which will run it for hours? Does $15 sound low enough? That’s what you can pay these days for an Android cell phone. The relentless march of economies of scale has finally given us cheap phones with great specs. These are prepaid “burner” phones, sold by carriers as a loss leader. Costs are recouped in the cellular plan, but that only happens if the buyer activates said plan. Unlike regular cell phones, you aren’t bound by a contract to activate the phone. That means you get all those features for $15-$20, depending on where you buy it.

The specs I’m quoting come from the LG Optimus Exceed 2, which is currently available from Amazon in the USA for $20. The same package has been available for as little as $10 from retail stores in recent weeks. The Exceed 2 is just one of several low-cost Android prepaid phones on the market now, and undoubtedly the list will change. How to keep up with the current deals? We found an unlikely place. Perk farmers. Perk is one of those “We pay you to watch advertisements” companies. We’re sure some people actually watch the ads, but most set up “farms” of drone phones which churn through the videos. The drones earn the farmer points which can be converted to cash. How does this all help us? In order to handle streaming video, Perk farmers want the most powerful phones they can get for the lowest investment. Subreddits like /r/perktv have weekly “best deals” posts covering prepaid phones. There are also tutorials on rooting and debloating current popular phones like the Whirl 2 and the Exceed 2.

Once you have your phone, the first order of business is to boot it up. Many prepaid phones try to force the user to go through an activation process. There is always a back door for installers to exit the process though. In the case of the Exceed 2, simply pressing volume up, volume down, back, and home quits out of the activation process.

Got root?

Some applications require root permissions. To achieve this, your best bet is to do a bit of Googling for your particular phone model. The XDA developers forums are a great resource for this. While prepaid phones don’t usually have communities behind them like flagship phones, you can often find at least some information on what it takes to root your particular device. The most well-known “root every device” application to date is towelroot, created by GeoHot. You might remember [George Hotz] aka GeoHot as the first person to jailbreak an iPhone. He also made the news by getting into a bit of hot water with Sony over some PlayStation 3 security holes. Towelroot uses a Linux kernel exploit (futex) to gain root permissions. Released in June of 2014, the futex exploit has been patched on most new phones. However, it hasn’t been patched on phones that receive relatively few updates – like prepaid phones. On the Exceed 2, Towelroot works perfectly, giving the user root without even requiring a reboot. Once the phone is rooted, a root privilege manager like SuperSU is needed to keep track of which applications should have root permissions. Once that is done, anything goes! We’ve found packages like BusyBox to be huge helps – especially when working at the console through Android Debug Bridge (ADB).

What do you want to hack today?

Between these low-cost phones and the used phones every family seems to have floating around now, there are a heck of a lot of devices out there waiting to be used. What can you do with a spare Android phone? Quite a lot. There has never been a better time to learn to code for the Android Platform. Android Studio is the current official development environment. If you know a bit of Java, it’s easy to jump in and start making apps. If you’re not a Java head but want to learn, there are tutorials all over the web to help get into the swing of things.

Not a coder? The swiss army knife of automating android devices has long been Tasker. Tasker allows you to set off simple scripts (called tasks) with triggers which can be anything from plugging in headphones to connecting to a particular WiFi access point, to pressing a button on the screen. Want your smart phone to announce your arrival home with your own theme music? Just set up a Tasker profile to play a song when it connects to your home WiFi router. Tasker supports plenty of actions natively, and can be extended with plugins. Scripting Layer For Android SL4A) even allows it to extended with Python scripts.

Moving into the hardware world, there are plenty of ways to get GPIOs from an Android phone. The Android Accessory Development Kit (ADK) is getting a bit long in the tooth, but it’s still a great way to interface an Arduino board like the Arduino Mega ADK with your device. Another option for getting into the hardware realm is the IOIO OTG board. As the name implies, this new version of the IOIO board supports the USB OTG standard. This allows it to connect a phone either as a host or as an accessory.  Need a simple wireless terminal for your project? Grab a terminal app and a Serial Port Profile (SPP) compatible Bluetooth module, and Bob’s your uncle. Interested in hacking with the ESP8266? There is an entire page of apps on the Google Play store dedicated to interfacing with everyone’s favorite low-cost WiFi module.

We’ve just covered the tip of the iceberg here. What kind of hacking would you do with a spare Android phone, or one of these low-cost prepaid devices. Let us know in the comments!


Filed under: Android Hacks, Featured
Hack a Day 10 Sep 18:01

Hand Controlled Robot uses Accelerometer

What do orchestra conductors, wizards, and Leap controller users have in common? They all control things by just waving their hands. [Saddam] must have wanted the same effect, so he created a robot that he controls over wireless using hand gestures.

An accelerometer reads hand motions and sends them via an RF module to an Arduino. This is a bit of a trick, because the device produces an analog value and [Saddam] uses some comparators to digitize the signal for the RF transmitter. There is no Arduino or other CPU on the transmit side (other than whatever is in the RF module).

From the video, it looks like a natural way to control a robot as long as you don’t mind duct taping the transmitter to your hand. Of course, if you are a real hacking geek, you might even consider that an advantage as you can pretend you are working on becoming a cyborg.

[Saddam] spends some time talking about how the accelerometer works internally, and we’ve covered that before if you are curious. It turns out the devices aren’t as much electronic as we usually think of them, but mechanical.


Filed under: Android Hacks, robots hacks