Tag Archives: Jianan Li

Constructing a musical staircase with the ATmega32u4

A Maker by the name of Amir Segal has created a portable musical staircase for therapy sessions with autistic children using an ATmega32u4powered board.

“We decided to build a wooden frame around each step, at the end of which there is a laser source on one side, and a photosensor on the other side. The data from the sensors is gathered by the board, [which] sends key press commands to [a] laptop via USB,” Segal explained in a recent blog post.

“For this version of the stairs we used photosensors that come with a built in digital output and a sensitivity potentiometer, [allowing] for simple programming. The tricky part is aligning the laser and the photosensor. The length of the stairs is about 175cm, so a laser misalignment of one degree results in a deviation of 3cm on the sensor side.”

As such, both components are attached to an L shaped bar. One screw connects the sensor to the L bar, while another screw connects the bar to the wood frame, allowing for rotation of the sensor. In order to connect the laser source to its L bar, Segal hacked a cable clip, replacing the nail with a screw.

“The system is cheap, easy to build, and works great if setup properly,” he concluded. “[At this point], the system is not sufficiently durable. Whenever the stairs are removed to storage and then returned to the staircase, setup is required again [so] we are working on a more durable version.”

Unsurprisingly, the above-mentioned musical staircase isn’t the first floor-based platform we’ve seen powered by Atmel microcontrollers (MCUs).

In November, Jianan Li and a team of Makers designed a wireless Atmel-powered MIDI floor piano for Duke University’s Hackathon, while Sean Voisen and his team at Adobe used Atmel ATtiny84 MCUs to build the “SenseIt” platform for kids to run, jump, play and create in a world of ‘extra large’ digital experiences.

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.

Playing Tetris on a breadboard with Atmel

Jianan Li has designed a breadboard-based Tetris game built around two Atmel microcontrollers (MCUs). As the HackADay crew notes, Li’s breadboard Tetris creation is so impressive that it probably should be considered “wire artwork.” To be sure, the layout of the ‘board and circuits are as elegant as the carefully written code.

“There are two microcontrollers at work, each running the Arduino bootloader. The main chip is an [AtmelATmega328 which is responsible for monitoring the buttons and controlling game play,” writes HackADay’s Mike Szczys.

“The other is an [AtmelATtiny85. The 8 pin chip listens to it’s bigger brother, playing the theme song when the game starts, and pausing or resuming to match the user input.”

No matter which way you slice it, this is definitely one of the most stellar interpretations of Tetris we’ve seen over the years. As some of you may recall, Tetris is a modern digital classic originally designed and programmed by Alexey Pajitnov in the Soviet Union. The very first version of the game was released on June 6, 1984, while Pajitnov was working for the Dorodnicyn Computing Centre of the Academy of Science of the USSR in Moscow.

According to Wikipedia, the name “Tetris” was derived from the Greek numerical prefix tetra- (all of the game’s pieces contain four segments) and tennis, Pajitnov’s favorite sport.