Using Arduino shields with the Raspberry Pi

Since the Arduino was launched years ago, many ‘shields’ or add-on boards providing additional functionality have been released. There are hundreds of different shields, from video capture shields to touch screen shields. Now that the Raspberry Pi is out in the wild, it was only a matter of time before a RasPi to Arduino shield bridge was created.

[Omer] calls his bridge ‘Ponte’ and it allows Arduino shields to be used with the incredible  horsepower of an embedded Linux system. While [Omer] originally expected to write the RasPi to Arduino software converter himself, but found WiringPi halfway through the build. Of course this build comes just a day after we saw a tutorial on controlling the GPIO pins on the RasPi, and we expect to see similar GPIO-hacking builds in the future.

Right now, the Ponte only supports Arduino Uno-sized shield, so the possibility of an all-in-one RepRap controller using the RAMPS motor driver is impossible for now. We expect that to change very quickly as more people get their RasPis delivered.

Monitoring the status of a unisex bathroom

Years ago, someone at [Chuck]’s job came up with the brilliant solution of an indicator to display if the unisex bathroom is currently vacant, a men’s bathroom, or a women’s bathroom. The old system worked well, but [Chuck] thought it would be a great idea to display the current status of the bathroom on the large TV in the office, saving his coworkers from getting up only to wait in line until the bathroom became vacant.

Like the previous paper sign, [Chuck]’s build has three statuses: a men’s room, a women’s room, and vacant with a manual dial that is turned whenever someone is entering or leaving. The new build vastly improves on the paper-based indicator by using a laser cut indicator on a rotary switch.

The electronics are dead simple; just an XBee and a Explorer USB board. Whenever the switch state is changed, the XBee sends a bit of data off to a mac mini and displays the status on the office TV. It may be funny to our immature sense of humor, but it’s still a very nice project.

Simple mod to keep your downstairs neighbors from hearing you pound the keys

[Mesoiam] managed to pick up a Viscount hammer weighted keyboard for pretty cheap. For those who are unfamiliar, Viscount makes keyboards that feel like you’re playing a piano, hammers and all. The only problem with this, as [Mesoiam] discovered, is that even when he’s jamming with headphones in, his friends down stairs can still hear the keyboard banging due to the vibration going through the stand to the floor. His resolution to this problem was to build some custom dampers to reduce the vibration. He built two brackets that fit over the stand and suspend the keyboard on two strips of flexible rubber. Quite a simple solution to a possibly annoying problem.

Converting a manual camera lens to use motorized zoom and focus

[Guy] wrote in to share this motorized camera lens project he recently finished. He really loved the zoom lens, but since both zoom and focus are manually controlled, he sometimes had trouble getting both set to the right place in time to take the shot. With modern DSLR cameras which allow video capture, he also wants to have the option of a smooth zoom that is always in focus. The solution was to add motors to the rings and control them with a Wii classic controller.

This hack really shines when it comes to the add-on hardware. He has some beautifully made rings which wrap around the focus and zoom rings on the lens. They are then held in place by a timing belt. These belts have teeth which key into the gears on a pair of servo motors. From there it’s a snap to drive the motors with an Arduino, connecting to the Wii controller with a breakout connector. You can see [Guy] showing off the build in the clip after the break.

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Controlling Raspberry Pi expansion pins with a web interface

For the lucky few who have a Raspberry Pi board in their hands, you can now use the GPIO pins as a web interface (German, google translation). [Chris] is turning this magical board is turning a small device that can play 1080p video into something that can blink LEDs via the web.

The build started with an example of driving GPIO pins under Linux. [Chris] cobbled together a bit of PHP and Javascript on the Raspberry pi. Whenever he goes to the website hosted on the Pi, he’s greeted with the status and direction of a couple of expansion IO pins.

On a semi-related note, [Tony] is building a GPIO MIDI interface for his Pi. Yes, he could just get a USB to MIDI adapter and call it a day, but this is a far more professional looking solution to all the MIDI goodness the RasPi will deliver. If you’ve got any info on other RasPi breakout boards you’ve seen, send them in on the tip line.

Building a prosthetic leg from scratch

[Radek] from Poland sent in a neat video of a bionic prosthetic leg he made for one of his patients. Even though [Radek] says it’s a ‘prototype of a prototype,’ we’d have to agree with him that it’s a very neat build that could provide inexpensive motorized prosthetic legs to amputees in the future.

[Radek] has been working on his project for about two years now, after building the motor and electronics by hand. The leg is powered by 1.5 kilogram battery pack – no details on the chemistry of the batteries, but [Radek] says it will last 12 hours on one charge. There are also small vibration sensors in the leg for a bit of feedback, and a few switches so the knee joint can be operated by the stump.

If you’re wondering where [Radek] got the proper tools and materials to make a carbon fiber prosthesis, he works for Carbon Prosthetics where builds simple prosthetic devices. His bionic leg creation looks really cool, and he says the final product will be much less expensive than the very high-end bionic prosthetic legs.

[Radek] was kind enough to share some more videos and a few pictures of his robotic prosthetic leg; you can check those out after the break.

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