Official Android Open Accessory Development Kit – It’s An Arduino

A new development kit for android was unveiled at the Google I/O 2011 developer conference that officially supports the Arduino.

It looks like Google took a cue from Circuits@Home, because the interesting part of this dev kit is the fact that the shield can be put into USB Host mode. That’s great for phones and tablets that can’t act as a USB host themselves. Google will also release the APIs for this Android/Arduino mashup for 3.1, but it will thankfully be backported to Gingerbread.

We covered the IOIO breakout board for Android last month, but the Google board will be based off of the Arduino Mega 2560, a far more capable device. Interestingly, it appears this board is available now for about $400 USD. We’re not so sure a hobbyist will be buying it at that price.

While this board doesn’t do anything you couldn’t do before with a bluetooth shield, it’s great to see a company supporting all the builders out there.

Arduino Magnetic Core Memory Shield

mag_core_memory

Magnetic core memory turns 60 years old today, and as a tribute [Ben North and Oliver Nash] have created a 32-bit magnetic core memory board for the Arduino.

Magnetic core memory was used from the 1950s through the 1970s, and provided a non-volatile means for storing data, as each magnetic core retained its orientation, even when the power was cut. While it sounds a lot like a modern hard drive, these devices were used in the same fashion as RAM is utilized today.

While the pair used surplus ferrite cores manufactured just before magnetic memory stopped being produced, they did allow themselves to use some modern components. Items such as transistors and logic gates were not available to the first magnetic core memory manufacturers, but the use of these items helped them complete the project in a reasonable amount of time.

Their final result is a magnetic memory board which can be used by any USB-enabled device and is reliable enough to withstand billions of read/write transactions.

DIY Sound Localization Sensor

sound_localization_sensor

Sound localization is very popular in law enforcement circles due to its accuracy and ability to quickly separate gunshots from other similar noises. These systems don’t come cheap, and after trying to build one himself, [Fileark] knows why.

He thought it would be neat to build a sound localization sensor based on how the human ear determines a sound’s source. Once he got started however, he realized just how hard it was to do localization just right.

He used an LM324N op-amp as a volume comparator, which he says works decently enough though he figures there are ICs out there that can do a better job. [Fileark] reports that the sound detector works well when the source is within about a foot of the sensors, but performance deteriorates at greater distances. He may consider using an ARM Cortex-M3 as his sound processor if he builds a second version, since the Arudino he used just doesn’t have enough power to sample and run calculations within the 10-50 microsecond window he requires.

Keep reading to see a video of his sound localization sensor in action.

Continue reading “DIY Sound Localization Sensor”

DIY Portal Turret Is… Looking Pretty Good.

[Ryan Palser] wrote in to tell us about his Portal Turret. [Ryan] set about making this Portal 1 style turret by first carving a Styrofoam form, bondo and waxing then casting molds of the various components. Anyone interested in mold making (like us) should check out all the pictures and comments in the stream. The turret’s camera lens style eye has some excellent detail including a laser cut aperture with text inlay. A couple LEDs behind the eye assembly provide the signature red glow and evidently [Ryan] also fitted the little guy with a red laser. An internal Arduino (Incident Resolution Chip?) takes ques from a PIR sensor mounted in one of the turret’s arms to play one of 17 sound clips through a sparkfun MP3 player shield. In order to fight repetition the sound module runs through a playlist of the 17 tracks then shuffles it before playing through again. Theme music can also be spammed by pressing a button in the back of the motion sensing arm. The turret can be battery powered or plugged into a wall socket for constant operation. All that’s missing are the Aperture-Brand Resolution Pellets. We would love to see this integrated with some similar turret projects previously featured here.

Are you still there? We have more Aperture Science stuff including a Sentry Turret, Weighted Companion Cube, and even a portal shirt. If you are interested in more model making check out the spectacular Daft Punk helmet build from a little while back.

Learning Electronics Concepts Step By Step

arduino

We realize that not everyone out there holds a degree in electrical engineering or has the ability to tell NPN transistors apart from PNP transistors by taste alone, so we occasionally like to mention things that appeal to the beginners in the crowd. While there is a clear division between Arduino supporters and detractors, it is hard to deny that the devices have their place, and can be quite useful when exploring certain electronics concepts.

For the supporters out there, [John Boxall] has put together a site jam-packed with Arduino tutorials covering a wide array of concepts and techniques. We have covered his work before in relation to specific topics, but we felt that his site deserved mention as a whole. His tutorials cover some of the most basic concepts such as lighting LEDs with the Arduino, and work their way to more advanced subjects, lesson by lesson.

He is not satisfied with simply introducing a concept and handing out a sketch that does the work. He takes the time to expand on the concepts, giving the reader enough detail to use their new-found knowledge in later projects. If you were to follow his tutorials from beginning to end, you would be exposed to LCD screen control, shift registers, real-time clocks, I2C bus communications, and more. These skills and concepts can be carried on to future projects as well as other micro controllers, making his tutorials a very valuable learning tool worth checking out.

Rebecca Black Running Accessory Also Promotes Running For Everyone Within Earshot

Last Friday, Friday we caught wind of [gvillenave]’s running accessory inspired by Rebecca Black, and we we we so excited, we so excited to bring this to you on Saturday, which comes after Friday.

[gvillenave] came up with the idea of using a song on the annoyance level of “Friday” to encourage a runner into keeping up a good pace. The concept is simple: if the wearer is running fast, the song will speed up. If the wearer is slowing down, the song will slow down and extend the agony.

The build uses an Arduino and [ladyada]’s wave shield coupled to an accelerometer. [gvillenave] included the code, and also wired up some LEDs to a pair of sunglasses that blink more often as the runner’s speed increases. The wave shield has a 3.5mm jack for headphones, but [gvillenave] graciously wired a speaker in, “so that you can annoy people around you, and not just yourself.” All this is packaged in a very nice 3D printed enclosure making for a great looking project.

There’s no word on the effectiveness of the negative reinforcement aspect of [gvillenave]’s build, but we suspect it will help her get down to the bus stop a little faster every morning.

Light Painting – Still Shots And Animations

[Kim Pimmel’s] been doing some really interesting light painting with an Arduino. In the past we’ve seen several light painting projects which use long exposures to capture moving LEDs, or moving LCD displays. But [Kim’s] stepping it up a notch, using cold cathode flourescent lamps, electroluminescent (EL) wire, and lasers. The vibrant colors put out by these sources make for some great photos, but that’s not all she’s got up her sleeve. After accumulating a ton of still photographs from various shoots she decided to edit them together into stopped motion videos.

After the break you can see that one method she used to make these images was to spin the light sources on a standard audio turntable. An Arduino is controlled through processing via Bluetooth in order to move the stepper motor-mounted lights while the record player spins. Add some futuristic music thanks to Daft Punk (which is exactly what she did) and you’re in business.

Continue reading “Light Painting – Still Shots And Animations”