Maker creates a robotic guitar to bring unseen data sources into the real world.
It all began nearly 30 years ago when Ben Reardon was awestruck by a robot playing a classical guitar at the 1988 World Expo in his hometown of Brisbane, Australia. While he may have only been a teenager at the time, he promised himself that he’d go on to build one of his own when he grew up. 27 years later, Reardon has indeed achieved his childhood aspirations by creating a pretty slick robotic player guitar — or what he calls the first “network time protocol accurate, Internet of Things connected, Big Ben chiming grandfather clock, firewall log playing, door chiming, guitar playing robot thingy.”
The Maker realized that all of the technological ingredients were available to bring the idea to life after attending SIGGRAPH 2014, and in order to first test out his concept, Reardon devised a prototype robotic tambourine using a vibrating disk, Raspberry Pi, some Python script, a few LEDs and a pair of piezo speakers.
“I wired up a vibrating disk (like the one you have in your mobile phone that makes it vibrate) into a Raspberry Pi GPIO pin. The vibrating disk sat just above the drum skin and vibrated when it received a current. The Pi was connected to the Internet and a python script tailed the firewall logs so that when the Pi was hit from an IP, the firewall blocked the connection and a current was sent to the vibrating disk, which then jumped up and down on the tambourine. Also at this point, the blue and red LEDs strobed in sequence and a pair of piezo speakers sounded in turn,” he writes.
Whilst this prototype was a mere proof-of-concept, it was a significant ‘hello world’ moment as the gap had been bridged between an esoteric real-time data source and the real world. Moving ahead, Reardon equipped his guitar with both an Arduino Uno (ATmega328) and a Raspberry Pi as well as a RC servo for each of the six strings. In addition, actual picks were employed to strum the harmonic sounds of the acoustic guitar. These were affixed to the servo horns using a screw at the pivot and a small copper pin. The Maker also ended up using aluminum extrusion to mount the servo — three per side to leave space for pick adjustments.
“The servo rig needs to be just right. It has to be stiff enough so as not to move, whilst still allowing the pick to be adjusted up, down and sideways so as to position the tip of the pick just so; critically plucking just enough string whilst remaining at the right angle and depth so as to stay clear and not get stuck — or it would never pluck the string at all,” he writes.
Altogether, the guitar featured six yellow manual buttons to operate and tune each pick up and down individually, along with two additional buttons to run pre-programmed routines. The six tuning buttons were controlled by the ATmega328 board, while the pair of pre-programmed buttons were monitored by the Pi. For some extra effects, LED lights were tasked with illuminating blue lights inside picks. To complete the project, Reardon only need 460 lines of code — Python and a bit of Bash — and Processing sketches for the Arduino.
Intrigued? Head over to the project’s official page here, or simply listen to the robotic instrument strum a few soothing sounds below.
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