Robotic Berimbau Plays Itself

April 2, 2011 by 10 Comments

berimbau

If you have ever seen capoeira, you have undoubtedly heard the music of a berimbau. If you are not familiar, Capoeira is a Brazilian art form that melds martial arts, acrobatics, and music. This graceful fighting form is often accompanied by the sounds of a berimbau, a single-stringed musical instrument comprised of a gourd, a wooden bow, and a steel string.

[Ivan Monsão] and [Paulo Libonati] have constructed what is considered to be the first robotic berimbau in existence, capable of playing music without any human interaction. The robot strikes the berimbau’s metal string, mechanically muting the gourd when appropriate, and even shakes the caxixi (a rattle) in time with the music.

The builder claims that the berimbau learns songs by “listening” and repeating rather than having songs pre-programmed into the system. We can’t see any evidence of that functionality from the video, though we’d love to see the learning process in action.

While we try to find our VHS copy of “Only the Strong”, be sure to take a look at the following video of the berimbau playing itself.

[Thanks, Camilo]

Continue reading “Robotic Berimbau Plays Itself” →

Manage Your Rechargeables At A Glance

April 2, 2011 by 17 Comments

If you enjoy photography, radio controlled vehicles, or any other activity that requires you to keep multiple sets of rechargeable batteries on hand you know how much of a pain it can be if you get a dead battery mixed in with your charged batteries. This easy approach to managing your batteries while on location does not require fancy electronics, meters or anything else that might pop into mind, but rather simple stickers and storage.

The first set of labels get stuck on the battery, offering a green and red color code along with a number so its easy to keep track of which group of batteries go where and to catalog date / life. The second set of labels gets attached to your storage compartment, when a battery is charged, place it in the box so the positive end is facing the green on the storage label, and when its dead just flip it around.

While this mainly focuses on AA batteries (and even shows you how to make a simple but effective holder out of some elastic band and staples) this idea can be used with just about any type of battery for a quick glance to see where you stand on juice.

Simple DTMF Decoder Pulls Numbers From YouTube Videos

April 2, 2011 by 28 Comments

dtmf_decoder

While many of us have banished land line telephones from our houses, there are still quite a few people who utilize POTS lines today. These analog phone systems use Dual Tone Multi Frequency (DTMF) signals in order to audibly represent all of the keys on a telephone keypad and place calls. [Brad] over at LucidScience decided that it would be useful to have a DTMF decoder on hand, and got busy building one.

His DTMF decoder box uses a CM8870 DTMF decoder chip, which you might assume is all you need to get the job done. This chip performs its duties very well, outputting a 4-bit binary code for each button press it registers, but that doesn’t do a whole lot of good without being able to represent those codes in a meaningful fashion. He first built a breadboard decoder circuit that would light 1 of 16 LEDs depending on the detected button press. This was well and good, but he decided that an Arduino-driven LCD display would work far better.

When he was finished, he had a compact decoder box with an LCD display, which accepts input from either an RJ-11 cable or an audio jack. He says that the audio jack is particularly useful for decoding tones from computer audio, such as YouTube clips. [Brad] praises the CM8870 chip, stating that it can pull phone numbers from pretty much any audio or phone signal you throw at it, regardless of quality. We think it would make a great basis for a telephone-based security system, if that was something that appealed to you.

Be sure to stick around to see his DTMF decoder circuit in action.

Continue reading “Simple DTMF Decoder Pulls Numbers From YouTube Videos” →

Awesome Portable N64 Keeps Your Games In Hand, Out Of Sight

April 1, 2011 by 19 Comments

n64_portable

[David] recently wrote us to share the portable Nintendo 64 he constructed with the help of the friendly people over at the ModdedbyBacteria forums. We are no strangers to N64 portables, as you may have noticed, but this one was just too good to pass up.

Sheathed in a metallic blue case, this console is an instant standout among the other portable N64 mods we have seen. As you would expect, he trimmed down an N64 console board and some various controller bits in order to fit them into the case, finishing it off with a 5″ PSOne display panel. A small fan protrudes out of the back side of the device, which seemed out of place at first. However, it not only keeps the console cool, but it can serve as a bit of a “kickstand” as well, if the console is placed on a flat surface. [David] also added a dongle for the bottom of the console, which allows him to use an external N64 controller if he so desires.

To be honest, one of our favorite features is that the game cartridges do not stick up from the back of the case when inserted. He included just enough room to allow the game to be completely hidden while playing.  Nice job!

Continue reading to see a video build log and demonstration of his portable N64.

Continue reading “Awesome Portable N64 Keeps Your Games In Hand, Out Of Sight” →

Bluetooth Bot Constructed From Thrift Store Rejects

April 1, 2011 by 11 Comments

bluetooth_bot

[John] wrote in to share his latest creation, an Arduino-controlled Bluetooth robot. You might remember him from one of his previous hacks, the Lawnbot 400. This time around, he has decided to scale things down a bit and focus his hacking on small R/C toys.

His Bluetooth bot was constructed using a cheap R/C tank he scored at a thrift store for about $1.50. He removed all of the bot’s parts, aside from the frame, the battery compartment, and the motors that drive the treads. He added in an Arduino, which he paired with an Ardumoto shield from SparkFun. The motor shield costs about $25, but he does have schematics available so that you can roll your own if you so desire.

A Bluetooth Mate was added to the car, which allows serial communication with any other Bluetooth device. Once everything was wired up, he paired the robot with his computer and got down to driving it by simply pressing keys on his keyboard.

It looks like a fun little toy to have around, and it seems fairly easy to construct. Check out the videos below of his robot in action, and be sure to check out his code/schematics if you are interested in building your own.

Continue reading “Bluetooth Bot Constructed From Thrift Store Rejects” →

Whistle To Make The Art Flow

April 1, 2011 by 3 Comments

A new project from [James] targets the iPhone with this wild generative art in an Augmented Reality environment (free) app for 3GS and 4 running running iOS 4+. Powered by the String augmented reality library, and written in C + OpenGL the combo present a power AR platform offering over 100,000 polygons on screen with no noticeable dip in frame rate.

The artistic part is influenced by noise the app is picking up through the microphone. Speaking, whistling or blowing at the device creates 3D generative art, which you are then free to explore in 3 dimensions. It would be interesting to see what it comes up with in a naturally noisy environment. Features also include variety of 3D shapes, color palettes, and settings that can be mixed to create “endless” combinations along with a good to have save snapshot feature.

Join us after the break for a quick video, and be sure to check out some of [James] other work, like  the Augmented reality business card

Continue reading “Whistle To Make The Art Flow” →