Chord Assist

By Rob Zwetsloot. Posted

With a built-in AI voice assistant, this accessible smart guitar can help almost anyone learn to play.

Learning to play the guitar can prove difficult for people with sight or hearing loss. Joe Birch’s accessible Chord Assist guitar is intended to make the process a whole lot easier for deaf, blind, and mute people.

In Joe’s family runs a condition known as retinitis pigmentosa, which causes tunnel vision over time; it has affected his mother, who is now registered partially sighted. “Being closer to people who have this condition opened up my awareness of how it can effect peoples lives,” explains Joe. “Currently, music is something that is not so accessible to everyone, so I started to think of ways in which it could become accessible – which is where the idea for Chord Assist came from.”

As well as an LCD screen, four-digit display, and buttons to show and select chords, Joe’s modified acoustic guitar features a Braille reader based on his earlier BrailleBox news-reader project. There’s even a vibrating progress indicator next to the reader, to indicate when a request is taking place.

In addition, the user can make a spoken request for a chord using the built-in mic and Google-based voice assistant, and hear a response via the speaker. Also capable of playing a requested note for tuning purposes, this system makes use of Joe’s Chord Assist app on the Actions on Google platform, which can also be used as a standalone learning aid on smartphones and other devices.

 Extensive controls and features include selection buttons, a mic and speaker, along with a segment display and LCD screen

Hidden components

The whole project took Joe around six months to complete. “The most difficult part was definitely the last stages of the build process – cutting the holes in the guitar and then putting all of the parts inside became quite a tedious task,” he recalls. “I originally had everything on prototyping boards, but components kept coming unplugged. Because of this I decided to solder everything properly on PCB boards, which improved everything here.”

All the electronic components, including a Raspberry Pi, are secreted inside the body of the guitar. “There’s actually a lot of stuff in there, but none of it is that heavy other than the portable battery pack.” It doesn’t seem to have an adverse effect on the sound quality either: “Initially I thought it was going to be a big problem, but when comparing it against my other guitar, there isn’t really much difference.”

 The Pi and other components, including an eight-channel relay for the solenoids in the Braille reader, are stuffed inside the body of the guitar

Turn it up

While Joe is happy with the project, he’s planning a few tweaks. “I’d like to add an amplifier and volume control to improve the functionality of the speaker. Another thing I’d like to add is real guitar tuning functionality – so something in the software that will analyse the note played and let the user know if the string needs to be tuned higher or lower. This isn’t yet possible with the Google Assistant, but would be a useful feature for users who might not have experience with tuning a guitar. I could also make use of the screen to instruct the user here and cater for the different accessibility needs.”

If you’d like to have a go at creating a similar project, Joe has open-sourced most of what is needed to build the guitar, apart from the program that runs on the Raspberry Pi which drives the user interface and GPIO for the components. “The wiring diagram and conversational bot are open-source, so someone could build it if they wanted to.”

Following feedback from users, Joe plans to iterate on the design to create more smart guitars. Since this project has struck a chord with us, that’s music to our ears!

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