Level up your Guitar Hero gaming with Nick O’Hara’s Jon Bot Jovi Guitar Hero robot. While Nick admits this is an expensive project (around $1000 to build), it’s something that was so “ridiculous, hilarious, and awesome” he felt he just needed to do it.
You’re halfway to shredding a Bon Jovi chorus perfectly on Guitar Hero and you can taste the fame. Problem is, you’re no Jon Bon Jovi. Or Peter Frampton. Or Slash. So you need Raspberry Pi to assist your rockstar dreams. Enter Jon Bot Jovi.
What is a solenoid?
A solenoid is just a coil of wire, but when you pass an electric current through it acts as an electromagnet, and a magnetic field is generated. When you turn the current off, the magnetic field goes away. Inside the coil of wire is a metal rod, when the current is on and the magnetic field is present, the rod is free to move in the direction of the field. In this way, a solenoid converts electrical energy into movement and the rod moves in or out of the coil depending on the current applied.
Here, a Raspberry Pi controls a bunch of solenoids as they press and release the buttons on the guitar controller to give Nick his god-like skills. Watch the build video on YouTube for a simple walkthrough of how this all works.
Building the mechanical fingers and solenoids was one of the trickiest parts of the build. Nick ended up burning through a lot of them as he’s new to robotics and didn’t understand the relationship between power, voltage, and current, so they burnt out quickly. Luckily, he found a robotics guy to give him a 30-minute crash course, which set the project on the right path. Heroes come in all shapes and sizes.
Note recognition was also far from an easy task. Nick originally tried to look at specific pixels on the screen, which worked for slow songs, but for faster songs it would miss around 30% of the notes. He eventually turned to OpenCV, but it took a fair amount of effort to hone the perfect filtering to make the note recognition accurate. Fiddly, but worth it.
Shred, guitar hero!
Nick’s favourite part of the project?
“Seeing Jon Bot Jovi absolutely shred on the guitar. Did you see how fast he’s strumming during Through the Fire and the Flames?!”
We love seeing a maker so happy with a final build and we wish we could come and play too! (We are similarly stunted in our guitar-playing abilities.)
Nick wrote a project post on Hacker News for those who are curious about the more technical details. And the original build video on YouTube is a wild ride, so check it out and subscribe to Nick’s channel.