WIP: A Photoplethysmography Graphical User Interface for Teaching Signal Processing Concepts

In this Innovative Practice Work in Progress, we present a Graphical User Interface (GUI)-based tool that uses the photoplethysmograph (PPG) to demonstrate fundamental signal processing concepts such as periodicity, noise, jitter, and peak selection, offering students an interactive learning experience. Extraction of the heart rate from the PPG has several steps, some appropriate for sophomore-level students in the signals and systems course, and others better suited for senior-level students in the digital signal processing course. For example, sophomore-level students can be exposed to concepts such as periodicity and statistical averages, which they see in signals and systems and introductory statistics courses. More complex topics such as peak selection and digital filtering are better suited to senior-level students. This GUI was deployed in a sophomore-level signals and systems course in the spring semester of 2024 to help students understand concepts related to statistics and periodicity. The GUI will be similarly deployed in a senior-level digital signal processing course in the fall semester of 2024. Assessment results show that the GUI helped students improve learning across multiple concept areas, and survey questions showed that students found the GUI to be helpful.