DIY Ultrasonic Acoustic Levitation

[Mike] saw a few videos of ultrasonic acoustic levitation rigs put together by student researchers. Figuring it couldn’t be that hard to replicate, he set out and built his own using surplus parts and whatever was sitting around his parts drawer.

The build began with a huge ultrasonic transducer from an old ultrasonic cleaning tank [Mike] picked up on eBay for $20 £20. He didn’t pick up the standard driver board, as those don’t have a very clean output – something desperately needed if you’re setting up a standing wave. He did manage to put a simple supply together with a 555 timer, a MOSFET and a 12 V transformer connected backwards, though.

The test rig is pretty simple – just the transducer sitting on a table with an aluminum plate sitting above it on threaded rods. By adjusting the distance between the transducer to the aluminum plate, [Mike] managed to set up some standing waves he was able to suspend small Styrofoam balls in. It’s not quite precise enough to levitate small chunks of sodium and water, but it makes for an excellent science fair-type project.

Continue reading “DIY Ultrasonic Acoustic Levitation”

Mario Plays Piano With A Little Help From Raspberry Pi

mario-piano

[David] has created his own live robot band to play live versions of the music and sound effects of NES games. Most of us who grew up in the 80’s and 90’s have the music of Nintendo games burned into our brains. While there have been some amazing remixes created over the years, [David] has managed to do something truly unique. Armed with an emulator, some software prowess, and a pair of Raspberry Pis, [Dave] created a system that plays game music and sound effects on analog instruments. A Yamaha Disklavier player piano handles most of the work through a connection to a Raspberry Pi. Percussion is handled by a second Pi.  Snare drum, wood block, and tambourine are all actuated by a custom solenoid setup.

The conversion process all happens on the fly as the game is played. [Dave] says the process has about ½ second of lag when played live, but we’re sure that could be fixed with some software tweaks. Continue reading “Mario Plays Piano With A Little Help From Raspberry Pi”

Advanced Transcend WiFi SD Hacking: Custom Kernels, X, And Firefox

[Dmitry] read about hacking the Transcend WiFi cards, and decided to give it a try himself.   We already covered [Pablo’s] work with the Transcend card. [Dmitry] took a different enough approach to warrant a second look.

Rather than work from the web interface and user scripts down, [Dmitry] decided to start from Transcend’s GPL package and work his way up. Unfortunately, he found that the package was woefully incomplete – putting the card firmly into the “violates GPL” category. Undaunted, [Dmitry] fired off some emails to the support staff and soldiered on.

It turns out the card uses u-boot to expand the kernel and basic file system into a ramdisk. Unfortunately the size is limited to 3MB. The limit is hard-coded into u-boot, the sources of which transcend didn’t include in the GPL package.

[Dmitry] was able to create his own binary image within the 3MB limit and load it on the card. He discovered a few very interesting (and scary) things. The flash file system must be formatted FAT32, or the controller will become very upset. The 16 (or 32)GB of flash is also mounted read/write to TWO operating systems. Linux on the SD card, and whatever host system the card happens to be plugged in to. This is dangerous to say the least. Any write to the flash could cause a collision leading to lost data – or even a completely corrupt file system. Continue reading “Advanced Transcend WiFi SD Hacking: Custom Kernels, X, And Firefox”

Desoldering Chips With Fire

Salvaging components is a staple of any electronic enthusiast, but many times those interesting chips – old 8-bit microcontrollers, memories, and CPUs found in everything from game consoles to old computers – are rather difficult to remove from a board. [Ryan] over on Instructables has a rather interesting method of removing old SMD packages using nothing more than a little fire and a pair of tweezers.

Obviously the best way to go about salvaging SMD components is with a heat gun, but lacking the requisite equipment, [Ryan] managed to remove a few SMD chips using rubbing alcohol as a heat source. In a properly controlled environment, [Ryan] filled a small metal dish with alcohol, set it on fire, and used the heat generated to remove a few components. Alcohol lamps are a common bench tool in a range of repair disciplines because the fuel is cheap and burns relatively cleanly (not leaving an unwanted residue on the thing you’re heating).

It’s an interesting kludge, and given [Ryan]’s display of desoldered components, we’re going to call it a success. It might also work for through-hole components, allowing for easy removal of old SRAM, ROM, and other awesome chips.

BeagleBone Black Does CNC With RAMPS

[Bart] Wanted to try controlling a CNC with his BeagleBone black, but didn’t want to invest in a CNC Cape. No problem – he created his own translator board for RAMPSLinuxCNC for the BeagleBone Black has been available for a few months now, and [Bart] wanted to give it a try. He started experimenting with a single stepper motor and driver.  By the time he hooked up step, direction, and motor phases, [Bart] knew he needed a better solution.

Several CNC capes are available for the BeagleBone boards, but [Bart] had a RAMPS board just sitting around, waiting for a new project.  Most RepRap fans have heard of the RAMPS – or Reprap Arduino Mega Pololu Shield.  In fact, we covered them here just a few days ago as part of our 3D Printering series.   RAMPS handle all the I/O needed for 3D printing, which carries over quite nicely to other CNC applications as well.   The downside is that they’re specifically designed for the Arduino Mega series. Continue reading “BeagleBone Black Does CNC With RAMPS”

Fail Of The Week: Smoking Pulse Sensor And BLE Disappointment

fotw-ble-and-pulse-sensor

We think [Thomas Brittain] is onto something. We often post to our personal blogs so that we have a reference to how we did something. But he also keeps a long post that documents his abandoned projects. It ends up serving as a quick start if he ever decides to pick up the torch once again. Lucky for us he’s included his failures in the write up. This Fail of the Week features the top two posts on his Incomplete Works page. The first is an attempt to make his own pulse sensor. The second is a miserable experience with a cheap Bluetooth Low Energy module.

Continue reading “Fail Of The Week: Smoking Pulse Sensor And BLE Disappointment”

A Spinning Beachball Of Doom That You Can Carry In Your Pocket

175353_115989

Need a way to tell the world that you’re mentally ‘out to lunch’? Or what about a subtle hint to others that your current thought process is more important than whatever they are saying? [Caleb Kraft] — who earlier this year bid farewell to Hackaday for a position with EETimes — is heading to the World Maker Faire in New York this weekend, and he decided to build just that device. If you’re heading to Maker Faire too, keep an eye out for his eye-catching Spinning Beachball of Doom. He was inspired by iCufflinks from Adafruit, and ended up with a great little device that is small enough to be worn, or just thrown around for fun.

A couple of weeks ago, we linked you to the Adafruit announcement of their new Trinket product line. [Caleb] wasted no time in finding a use for the tiny microcontroller board. He paired it with the Neopixel LED ring, and had it working with just a tiny tweak to the test code. He then used DesignSpark Mechanical to design a 3D-printed case… the most complicated part of the project. It’s too bad his original plan to power the whole thing with button cells didn’t work out, because it could have been a neat (albeit expensive) upgrade to LED throwies. That said, [Caleb] mentions that a small LiPo battery would be a good alternative.

This is a fun little project that most anyone could throw together in an afternoon. Don’t be surprised if we start seeing these show up more and more.

To see what it looks like in action, check out the video after the break.

Continue reading “A Spinning Beachball Of Doom That You Can Carry In Your Pocket”