Tag Archives: MDF panels

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.