Continuing the series about designing an applied electronic circuits course for our bioengineering majors (with more project ideas and another project idea), I want to talk about another lab-oriented view of what we want the course to teach—what lab skills they should have by the end of the course. Eventually, I’ll get around to textbook-concept view of the course, but I’m trying to stay away from that for a while, since the course we are trying to replace was faulted for being far too theoretical. I want to start with the practical goals first, and work out form there what are the most important theory topics and what order they should go in.
Again, this is all very preliminary brainstorming—I have to talk with my co-instructor about what lab skills are feasible to teach in the class, which ones he sees as essential, and which are beyond the scope of the class. Here is a tentative list of technician-level skills that every engineer should have:
- Reading voltage, current, and resistance with a multimeter.
- Using an oscilloscope to view time-varying signals:
- Matching scope probe to input of scope.
- Adjusting time-base.
- Adjusting voltage scale.
- Using triggering.
- Reading approximate frequency from display.
- Measuring time (either pulse width or time between edges on different channels)
- Using a bench power supply.
- Using a signal generator to generate sine waves and square waves. Hmm, only the salinity conductance meter uses an AC signal so far—I may have to think of some other project-like labs that need the signal generator. Perhaps we should have them do some capacitance measurements with a bridge circuit before building a capacitance touch sensor.
- Using a microprocessor with A/D conversion to record data from sensors.
- Handling ICs without frying them through static electricity.
- Using a breadboard to prototype circuits.
- Soldering through-hole components to a PC board. (I think that surface-mount components are beyond the scope of the class, and freeform soldering without a board is too “arty” for an engineering class.)
There are probably a lot more skills to add to this list, which I haven’t thought about yet, and details within these skills that I’ve not thought about. Luckily, my co-instructor has been teaching beginning students how to use electronic lab equipment for over 15 years, so I’m sure he knows what needs to be covered.
The bigger problem here is motivating students to want to develop these skills quickly—the EE and computer engineering students see the skills as directly related to their chosen profession, but the bioengineers will need to know why anyone would care about resistance, voltage, or current. Getting a simple biosensor in right from the beginning would probably help. I wonder if we should start with a thermistor lab for resistance, voltage, and current measurement. How soon can we cover voltage dividers, so that they can design a resistance-to-voltage converter for interfacing to the ADC on an Arduino? Can we do that in the first lab?