[Ania] wrote in to let us know her team had finished the Multixylophoniomnibus and that they have posted an extensive writeup about it. We covered this augmented xylophone when it was still in development at the beginning of this month. Originally they wanted to use mallets wrapped in tinfoil as switches that close when they contact the metal keys, something akin to matchbox cars as a switch. This plan was thwarted when they realized the paint surface insulated the metal keys. At this point they switched to piezo sensors which turned into an odyssey of trial and error to achieve a reliable input for the Arduino to monitor. In the end they got it working with around forty lines of code, interfacing six boxes containing a different type of noisemaker.

See the finished instrument played in the video after the break. Alas, the addition of the piezo sensors do impede the resonance of the xylophone keys, but we still like it! There’s something reminiscent of the beginning of Pink Floyd’s Money when this is played.

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Tube prototyping station

[Gio] enjoys using vacuum tubes in his projects. He designs the circuits using a CAD program but was finding that there is no substitute for actually building a prototype before heading to a final design. To make this process easier, he built his own tube prototyping station.

At the top of the board he’s got three different sizes of tube sockets with the pins from each wired as common. The nine pins from the sockets break out to a terminal strip where they can be interfaced with a solderless breadboard. For added versatility he’s included terminals to tap into some RCA jacks, as well as a 100 kOhm variable resistor. We’d bet this is not something that you can find ready-made, but it sure does look a whole lot better than a workbench full of components alligator-clipped together.

Remote uses no batteries

How often do you change the batteries in your television remote control?  Yeah, basically never. But that’s a tribute to how efficient the device is and not a reason to overlook this development. NEC is showing off a remote control that uses no batteries. Power is generated using the piezo effect that occurs when a button is pushed. That is to say, when a crystal is compressed it emits a tiny bit of electricity which is harnessed and used to power this device. This is the same principle that is used in the electricity producing sidewalks tested in Japan.

It’s pretty phenomenal that they can run the device using this method. Right now there’s only a handful of buttons but we’re sure there’ll be advances in the technology. There’s a ton of use for this if it can be miniaturized. It is using radio frequency instead of infrared, making it a useful development in wireless doorbells, garage door openers, key-less entry fobs for your car, and many more applications.

[Thanks das_coach]

USB accelerometer controller

As you can see above, there is no wiimote in that accessory steering wheel. There is, instead, a home-made accelerometer controller that connects to the pc via USB. Based around a PIC 18F2550 and a 2 axis accelerometer, this device is detected by windows as a standard controller. The schematic and source code are available on his website. He says it can also be used as a “motion mouse”. You can see a video of that after the break.

When we first saw the video, we thought it might be the same person as the accelerometer controlled maze project, due to the wiimote steering wheel casing.

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