The Essential Guitar Pedal Kaden Fischer Project Mentor(s): Lad Holden
Electric Guitar pedals are used in music to analyze, shape, and modify audio signals in real time. As digital technology advances, embedded systems have been implemented into many guitar pedals. This project focuses on the development of a guitar tuner/volume pedal combo using a Microchip dsPIC33 microcontroller for its Digital Signal Processing (DSP) capabilities. There is a footswitch that switches between tuning mode and volume mode. While in tuning mode, the system filters an analog guitar signal with a two-stage active bandpass filter to condition the signal for input to the microcontroller’s Analog to Digital Converter (ADC). A real time pitch-detection algorithm based on autocorrelation is used to estimate the fundamental frequency of the input signal. Additional techniques have been implemented such as DC offset removal, parabolic interpolation, and output smoothing to further enhance the accuracy and stability of the circuit. The detected frequency is compared to a lookup table, and the corresponding note is displayed using a 7-segment display and two LEDs to indicate whether the input signal is flat or sharp of the displayed note. While in volume mode, the guitar’s signal is modulated by a rocking footswitch that controls a potentiometer, and the signal continues down the signal path of the pedalboard. This project aims to merge a tuner pedal and volume pedal into one smaller footprint. Presentation Type: Poster Presentation (May 21, 9:30am–3:00pm) Keywords: Embedded systems, Digital Signal Processing (DSP), Audio signal processing, Analog to Digital Converter (ADC), Pitch detection SOURCE Form ID: 82 Orchid Mantis is a rocket being submitted by the CWU rocketry team for the 2026 IREC competition. The payload of a rocket is the scientific mission of the rocket. The mission of the Orchid Mantis is to deploy a student developed CubeSat, a small satellite, 600 feet above ground level using solenoids, and then release a parachute to slow its descent. Inside of the rocket, a dampening system reduces the vibration on the CubeSat. In the rocket itself and the CubeSat, a Raspberry Pi Pico and breakout boards measure the barometric pressure, acceleration, and rotation rate. The data is written on a microSD card. The acceleration and rotation rates of the two circuits are compared to measure the vibration dampening done. Barometric pressure is used to determine altitude. At 600 feet above ground level, a signal is sent from the Pi to a MOSFET driver, withdrawing the solenoids, and a spring pushes the cube out of the payload. Then, inside of the CubeSat, a servo is turned 90 degrees to release a spring mechanism, expelling the parachute. Presentation Type: Poster Presentation (May 21, 9:30am–3:00pm) Keywords: Rocketry, Electronics SOURCE Form ID: 106 Orchid Mantis Payload Electronics Brandon Greenleaf Project Mentor(s): Lad Holden
53
Made with FlippingBook interactive PDF creator