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biologic sensing/systems research

Table of Contents

EEG

GSR

../images/gsr1.jpg

Galvanic Skin Response (also for plant sensing):

Several circuit designs were tested using DIY electrodes based on:

http://extremenxt.com/gsr.htm

with copper tape and with aluminium tape. The simplest voltage divider circuit as detailed at:

http://www.schematicsforfree.com/archive/file/Computer/Circuits_using_a_PC/BIOFEEDBACK_MONITOR_PC_BASED.PDF

was also tested and gave reasonable results when compared to more complex Wheatstone bridge style detailed below.

Kicad files:

http://1010.co.uk/gsr1.tar.gz

This design uses OPA336 and follows:

http://courses.cit.cornell.edu/ee476/FinalProjects/s2006/hmm32_pjw32/index.html

Lie detector from Elektor (date?):

http://1010.co.uk/images/luge1.jpg

http://1010.co.uk/images/luge2.jpg

Links and overview: http://www.chris3000.com/archive/galvanic-skin-response/

Simple lie detector: http://www.hackcanada.com/ice3/wetware/lie_detector_circuit_2.html

GSR with DIY electrodes: http://extremenxt.com/gsr.htm

http://regexp.bjoern.org/archives/000187.html

http://web.media.mit.edu/~msung/VitaMon/vitamonschematics.htm

Plant sensing

With reference also to: http://lib.fo.am/plant_sensing

Electricity in plants

Scott, Bruce I. H., "Electricity in Plants", Scientific American, Oct. 1962, S. 107-115

at: http://www.r-j.de/literatur/electricity.pdf

"Electrical disturbances similar to the nerve impulse are associated with a number of plant life processes. It seems likely that these currents and fields somehow influence plant growth and development"

[p107]

The root of a bean shoot growing a weakly conductive medium, for example, is found to act as an electric generator sending tiny current into the medium and back through the root […]

The instrumentation must be highly sensitive, because only about a hunderdth of a microampere flows across a square millimeter of root surface […]

Without any stimulation the potential near the root starts to oscillate in a rhythmic fashion, the oscillations continuing for perhaps several hours […] The periods of oscillation for the roots we have studied are about five minutes.

[p110]

Note also: solutions of potassium chloride or sodium chloride

Karlsson, L., "Instrumentation for Measuring Biolectrical Signals in Plants", The Review of Scientific Instruments, Vol. 43, Nr. 3, March 1972, S. 458-463

at: http://www.r-j.de/literatur/karlsson1.pdf

Remote Biodynamic Sensing and the "Biogram" by Michael Theroux

at: http://www.borderlands.com/newstuff/research/rbs.htm

Detecting Biodynamic Signals by Michael Theroux

[referring to the work of L. George Lawrence inc. schematics]

at: http://www.borderlands.com/archives/arch/detectin.htm

L.George Lawrence: More Experiments in Electroculture

at: http://www.swtpc.com/mholley/PopularElectronics/Jun1971/PE_Jun1971.htm

Further general links

Author: root <m@1010.co.uk>

Date: 2010-07-13 19:32:22 BST

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