"Mechanical engineers are not good at circuits." Challenge
accepted! As part of an electrical engineering class I took
at Princeton, I was involved in a partner project to design
and build an electrocardiogram circuit, with a creative
visualization component.
The design featured instrumentation and variable gain amplifiers to
augment the signal gathered from electrodes on the patient's skin. From
there, the signal went through band-pass and notch filters to get rid of
high frequency and 60 Hz "outlet" noise, culminating in either an oscilloscope
display or our custom visualization circuit. Our circuit would rotate a motor and
alternate LEDs in sync with the patient's heartbeat.
This was a great exercise in analog circuit design, LTSpice simulation,
breadboarding, and the dos and don'ts of soldering.