P770: Inexpensive Arduino-based instrumentation for signal processing in the instrumental analysis laboratory
Computer-based instrumentation is commonplace in academic and industrial laboratories, but many students view these instruments as black boxes with little understanding of their inner workings. Instrumental analysis courses peel back some of the layers, but it can be difficult to give students sufficient access to the instrumentation to experience firsthand how certain design decisions and signal processing techniques can impact the quality of their collected data. We have adapted an inexpensive Arduino microcontroller to handle data collection from a pH electrode and drop counter to give students the opportunity to see how changes in sampling rates, signal averaging, and bit depth in analog-to-digital conversion affect their results. Different levels of abstraction are easily achieved, from having the students work with the raw digital counts to calibrated pH values suitable for use in general chemistry or analytical chemistry experiments. Additionally, the data can be processed in real time for the students as they perform an experiment (such as an acid-base titration), or the raw data can be saved for students to perform their own processing techniques afterwards.