skin conductance

[JobSteve]

Hi,

I have access to a NI-DAQmx and I need to measure the skin conductance of a subject. I need to make theskin conductance sensor using what is already available at the lab (common electronic stuff). Would anyone know how I would go about making one?

Many thanks,

Steve

[jschwartz]

Hi Steve,

 What DAQ hardware are you using?  It sounds like you are conducting a resistance measurement. With most NI DAQ hardware, you can only measure voltage and current.  We do have some modules that will measure resistance, you can find these here.If you are going to measure resistance, you will need either a known voltage or a known current, measure the missing one then use Ohm's law to solve for resistance. Be careful with what voltages and currents you are using so you don't shock yourself.  I would build a your circuit, then test with a known resistance like a resistor.

[JobSteve]

Hi,

I'm using the USB one. Would it be possible to use it if I build a GSR circuit similar to the one here: http://instruct1.cit.cornell.edu/courses/ee476/FinalProjects/s2006/hmm32_pjw32/index.html#SHDesign?

Many thanks,

Steve

[jschwartz]

Hi Steve,

It looks like this circuit will work because the researchers in the link were measuring a voltage then converting that into a resistance.  As long as you are measuring voltages within the specifications of the device, you will be ok.  You can find the specifications by searching for your device at ni.com. Your device name will be something like USB-XXXX (the Xs are the device number).  It looks like you will be measuring small voltages so you shouldn't have to worry about exceeding the capabilities of the DAQ device.

[FMC]

Hi Steve,

I am looking to do the same thing (create a GSR to interface with labview) and I was wondering if you could help me get started. How did yours work? What parts did you use?

Thanks,

Fiona