Signal Processing, Programming, and Mechanics by Brendan M Hayes

Abstract

This thesis describes the construction of an automatic guitar tuner—a mountable device that can automatically tune the strings of a guitar to specific pitches with minimal user input. The goal is more than just to build and showcase a finished product, and so both the beginning and intermediate steps are given as much treatment as the final prototype. Avenues of research and drafting that didn’t serve to be useful in the final construction of the tuner are also described in this thesis, since they were all equally vital to finding more practical alternatives. The basic mechanics of the guitar and its operation prove to be a necessary starting point in understanding the most fundamental requirements of the project. Then with a detailed model of a guitar in mind, this thesis explores the science behind sound waves, our methods of their interpretation, and how they ultimately come to serve as input for the device to perform accurate adjustments. Finally, the component electronics and programming models utilized to make the prototype a reality are thoroughly detailed, including a rigorous documentation of problems encountered during implementation and the troubleshooting patterns that proved the most effective. All relevant software and hardware is also documented, including numerous workflow utilities that greatly streamlined the project and facilitated its completion.