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Why teach circuits to bioengineers?

I’ve been posting quite a bit on the design of the labs for the new applied circuits course we are designing for bioengineering (and other) students,  but I’ve not yet clearly articulated why we...

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What sensors for circuits class?

What sensors are appropriate to use in a sensor-focused circuits class?  I listed a bunch that I’ve been thinking about in Why teach circuits to bioengineers?, but in this post I want to focus a bit...

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Capacitive sensing

I decided that it was time to try a new circuits lab today.  Although I have the INA-126 instrumentation amplifier working (with a 220Ω gain resistor for a gain of about 370), and I did get some EKG...

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Capacitive sensing, part 2

The obvious next step with the capacitive sensor is to make the sensor actually control something.  This is not essential for the circuits class—for that class it is better to have the students viewing...

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Capacitive sensing with op amps

I’m not very happy with the lab exercise in Capacitive sensing.  The basic design questions are good: What capacitance do we add by touching something? What frequency should the oscillator run at...

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Capacitive sensing with op amps, continued

What more can I do (or, more importantly, have the students do with the Capacitive sensing with op amps? The circuit that I gave in that post has several parameters.  Perhaps the students should try...

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Phototransistor

I started on the next series of experiments today: LEDs and photosensors.  I tried hooking up a red LED to the output of my signal generator together with a 1kΩ series resistor to prevent excessive...

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Synchronous demodulator

In Phototransistor, I suggested modulating and LED with a  a 1kHz square wave, passing the light through an earlobe, detecting the light with a phototransistor (or photodiode) then demodulating the...

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Pulse detection with light

I decided I wanted to try shining light through my earlobe and detecting my pulse optically. The hardest part of this was coming up with a way to hold the light-emitting diode and phototransistor in...

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Giving up on light-based pulse sensor

I’ve pretty much decided against using the LED/photodetector pulse sensor as a lab.  The mechanical setup for aligning the optical components is too off-topic for a circuits class, and the amplifier...

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Looking at bioengineering measurements courses

In  Giving up on light-based pulse sensor, I discussed the difficulty I was having in finding comparable courses to borrow ideas for labs from. In the comments kcab suggested “I would look first under...

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Order and topics for labs

I had a good discussion with Steve P. this afternoon about the order and purpose of the labs I’ve designed so far.  He’ll be putting together a list of EE topics we have to cover to coordinate with the...

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Supplemental sheet for lab, draft 1

In my previous post, I said that I would post drafts of my supplemental sheets describing the course here on my blog, to get feedback before submitting them. Since I’ve been thinking more about the...

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Supplemental sheet for lecture, draft 1

I did a draft supplemental sheet for the lab course, which is nearly complete, though there are 2 labs that need some more work (the phototransistor lab and characterizing fluidics).  I also need to...

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Supplemental sheets, draft 2

This post updates  and replaces the Supplemental sheet for lecture, draft 1 and Supplemental sheet for lab, draft 1 Lecture Course Undergraduate Supplemental Sheet Information to accompany Request for...

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Capacitive sensing with Schmitt trigger

Capacitive sensing with op amps and Capacitive sensing with op amps, continued used a rather complicated circuit to make a Schmitt-trigger oscillator out of op amps: Modified circuit for longer period....

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Hysteresis lab

Schmitt-trigger oscillator. Since I decided in Capacitive sensing with Schmitt trigger to use an off-the-shelf Schmitt trigger chip (like a 74HC14) and a very simple oscillator, I needed to rethink the...

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Hysteresis board

Now that we’re using a 74HC14 Schmitt trigger in the capacitive touch sensor for the hysteresis oscillator, that lab can be the first soldering project, in addition to learning about hysteresis. I...

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Supplemental sheets, draft 3

This post updates and replaces the Supplemental sheets, draft 2. It reflects the redesign of the course based on running a prototype version of the course in as a group tutorial in Winter 2013. Lecture...

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Sounds like my course

I’ve been reading an infrequent blog by a freshman at Olin Engineering, because it is one of the schools that my son is considering applying to.  He likes the idea of project-based learning, though he...

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Electronic sensors for water quality

I just read an article in AEE – Advances in Engineering Education—A Journal of Engineering Education Applications, SENSE IT: Teaching STEM principles to middle and high school students through the...

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New phototransistor lab

In Phototransistor I talked about one possible phototransistor lab, that looked at the response speed of a phototransistor, as a function of the load resistor.  I rejected that last year as...

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Hysteresis lab on KL25Z

Relaxation oscillator used in the hysteresis lab. The “variable capacitor” in this schematic is a person’s finger and a touch plate made from aluminum foil and packing tape. I spent today writing code...

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