Tag Archives: Sense It

Building an Atmel based wireless MIDI floor piano

Jianan Li and a team of Makers recently designed a wireless MIDI floor piano for Duke University’s Hackathon. According to the Hackaday crew, a DIY Pressure Plate for a haunted Halloween house featured on the popular website served as the initial inspiration for the wireless MIDI floor piano.

“Having only 24 hours to compete in the Hackathon, they had to choose something that was fairly easy to build out of cheap materials, and quick to assemble. This was just the ticket,” explained Hackaday’s James Hobson.

“The piano features 25 of the aluminum foil pressure plates, whose state are read by the [Atmel-based] Arduino Mega. This is then transmitted by an XBee radio to an Arduino Uno (ATmega328), which acts as the receiver for the laptop that processes the signals. They even added a remote control using Atmel’s ATtiny85 to allow for octave and instrument changes – it uses an XBee to communicate back to the Uno.”

Unsurprisingly, the above-mentioned pressure-sensitive wireless floor project isn’t the first that we’ve seen powered by Atmel microcontrollers (MCUs). Indeed, earlier this year, Sean Voisen and his team at Adobe were asked to build “something new” for the Children’s Creativity Museum in San Francisco.

By August, a digital-physical environment for kids called “Sense It” was up and running. With a 14′x8′ touch-enabled LED wall and a 14′x12′ pressure-sensitive floor, the platform can best be described as a place for kids to run, jump, play and create in a world of ‘extra large’ digital experiences. Sense It is built around a system of pressure-sensitive resistors placed under MDF panels, comprising a total of twenty-one 2′x4′ tiles, each one including 8 pressure-sensitive resistors and an ATtiny84 based platform.

Interested in learning more? Additional information about SenseIt can be found here, while the wireless MIDI floor piano project page is available here.

Building a pressure sensitive floor with Atmel’s ATtiny84

Sean Voisen and his team at Adobe were recently asked to build “something new” for the Children’s Creativity Museum in San Francisco. Several months later, a digital-physical environment for kids called “Sense It” was up and running.

“With a 14’x8′ touch-enabled LED wall and a 14’x12′ pressure-sensitive floor, Sense It is a place for kids to run, jump, play and create in a world of ‘extra large’ digital experiences,” Voisen explained in a recent blog post.

“As part this project, I was tasked with designing and building the pressure-sensitive electronic floor. I call it the ActiveFloor. At 168 square feet with one pressure sensor per square foot, it is by far the largest electronics project I have worked on to date.”

As the HackADay crew notes, a camera-based detection system couldn’t give Voisen’s team the required precision, so Sean decided to use pressure-sensitive resistors placed under MDF panels. Ultimately, the ActiveFloor comprised a total of twenty-one 2′x4′ tiles, each one including 8 pressure-sensitive resistors and an ATtiny84-based platform.

“I was already very familiar with Atmel microcontrollers, and it was cheap, readily available, and had just the right number of pins for the application,” Voisen continued.

“Though the ATtiny84 does have 8 single-ended ADC channels, most of these pins ended up being used for other applications. As a result, I used only 1 ADC and added a 74HC4051multiplexer for selecting sensor input.”

Interested in learning more? Additional information about the ActiveFloor can be found here on Sean’s official page.