Measure Electrodermal Activity

cicatrix

Hi

I have to use the microcontroller kit for some biomechanical applications for a project. I would really like to do something with measuring Electrodermal activity of the skin. I have the Propellor Education Starter Kit and have started working on labs in the book that came along with that. Any help with starting this or any other interesting bio mechanical application for the propellor chip will be of great help.

Thanks!

Beau Schwabe

You might try modifying your search to include "Myoelectric" which involves measuring the electrical activity of muscles at the transcutaneous level.

In any case, you will most likely need to use an instrumentation style of Op-Amp to minimize any DC biasing on the inputs as well as operate the Op-Amp in differential mode to filter out any common mode interference since your signals are going to be so low. If I remember correctly a valid myo-electric signal can range in the 10s of micro amps to 100's of micro amps depending on the location of the sensors and physical health of the individual.

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Beau Schwabe

IC Layout Engineer
Parallax, Inc.

Peter KG6LSE

I would LOVE to see a 99$ prop ECG 3 lead kit sold / made ....
it would be a whole lot lighter then useing my lifepak 10 for fun tests . and the same guts could dubble as a O scope...

Peter KG6LSE

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"Carpe Ducktum" "seize the tape!!"
peterthethinker.com/tesla/Venom/Venom.html
Never underestimate the bandwidth of a station wagon full of tapes hurtling down the highway. —Tanenbaum, Andrew S.
LOL

Leon

Silver/silver chloride electrodes are generally used for lab GSR studies, with electrode jelly. Many years ago I designed a system for detecting eye position showing the direction of gaze on a video image, using EOG with those sort of electrodes. I used very expensive isolation amplifiers - basically instrumentation amps with capacitive barriers - for safety.

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Leon Heller
Amateur radio callsign: G1HSM

Post Edited (Leon) : 4/4/2010 12:50:09 AM GMT

Spiral_72

There are several toys on the market that "supposedly" do this very thing. Mattel make one. Another is the Star Wars "Force" or something like that. The Star Wars one has been communicated with on Hack of the day.com It'd make you life easier if you could find one of those!

A digital VOM seems to detect varying continuity in the skin Meg-ohm range.... if that helps.

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"puff"...... Smile, there went another one.

MakroRageR

Hi there,

I am just about to start some EDA measurements in form of nonspecific SCR during relaxation (to access "electrodermal lability" trait) and I would like to ask, how to correct interindividual variance (range correction).
Has anybody any experience with this issue?

Thank you.

M.

PropGuy2

I worked with biological agents years ago. We used infared, visual and ultraviolet Luminance to detect germs, etc. Hint - study jellyfish to get an insight to how this works. It is a new field and shows great potential for anyone who wants to put the time in...