eeg block diagram using labview

[siju]

iam doing a proj on acquiring electroencephlograph using labview

fill me with details regarding the hardware part [circuit diagrams]

& also d block diagram

[Travis_W]

Hi Siju,

Thanks for posting on the NI forums!  We definitely want to help you out with your application.

Although I'm not farmiliar with operating an electroencephlograph, I am an expert at LabVIEW, Data Acquisition, and Instrument Control.  Tell me, how will your eeg connect to your PC?  Are you using an NI Data Acquisition Board for analog input?  Are you using a serial or GPIB cable to communicate with the eeg?

With a little more information, we should definitely be able to point you to some code to get started with this application.

Have a great day!
Travis W

Message Edited by Travis W on 01-31-2007 09:24 PM

[siju]

hi Travis

Thanks for replying to me.

i have just finished  outline course of LabVIEW && AM SERIOUSLY INTERSTED in going on with it.

it would of tremendous help if u provide us with some blueprints done in labview for eeg atleast  forwad it to your  forums and share your wider links with us

am planning 2 use d card of NI

NI USB  6009

8 i/p 14 bit

multifunction i/o

[siju]

it is not like that am going to connect the real eeg machine to pc

rather am planning to replace the entire real machine with an analogy made on the platforms of

labview.

we are planning to use the electrodes to acquire the signal and finally bring it out on labview display

[Ed W]

Hi Siju,

It is my understanding that the typical signal measured by an EEG is on the order of 0.001 – 1mV.  This is far too small to be measured by the USB-6009, which has an absolute accuracy of 1.53mV at the smallest input range.  You could apply some form of amplification to your signal before it goes into the USB-6009, but this may further decrease the accuracy of your measurements.  In addition to this, the USB-6009 is not FDA approved – it is missing the isolation required for approval – so connecting it to a human’s brain is obviously strongly discouraged.

However, if this is not the nature of your tests, and the ultimate goal of your project is to simply measure an analog signal, your current system will work fine for this application.  If you’re new to LabVIEW and DAQmx, then I would recommend getting started with the DAQ Assistant to start acquiring your analog signal.  This can be found on the functions palette on the block diagram by going to Measurement I/O >> NI-DAQmx >> DAQ Assistant.  The attached picture shows how to setup the DAQ Assistant for continuous analog acquisition. 

In addition, there are many examples in the LabVIEW Example Finder; this can be found by going to the Help menu >> Find Examples >> Browse to Hardware Input and Output >> DAQmx >> Analog Measurements >> Voltage.

I hope this helps.  Good luck with your application.

Ed W.

Applications Engineer

National Instruments

[siju]

Thanks for responding

i would definitely try on your advice.

As you have said, my idea also includes an amplifier part before the signal is fed to the daq card.

Am planning to put an instrumentation amplifier  between the sensors[electrodes] and the  card to provide the sufficient amplification for the card to read the signals.

I request some help regarding the amplifier design[hardware].

moreover, some information regarding the block diagram  would be quite helpful.

Pass on some details ( blueprint of block diagram) conveying the same.

Just fill in me with an example with the idea just being that thesignals are acquired  and  after certain filtering  process  and amplification is displayed graphically on the labview frontpanel.

  i  have just started with labview and am not quite familiar with the tools  so am looking forward for help from  masters in labview

[AnalogKid2DigitalMan]

Man, there's like 3 different posters all asking about EEG this new semester just blatantly asking for the assignment to be handed to them.

Time to put those brain waves to work, guys!

[Ed W]

Hi Siju,

We don’t have examples of the block diagram setup for this specific application.  However, we do have plenty of DAQmx examples in the Example Finder in LabVIEW.  I would recommend using these examples and/or the DAQ Assistant to get started.

As far as the hardware is concerned, we don’t provide schematics for instrumentation amplifiers.  However, there are a lot of good resources online that should help you get started with the design.

Ed W.

Applications Engineer

National Instruments

[kapillohia]

Hello sir! i gone through these posts and i think u can help me.

I am working on the same but i have to acquire EMG using PCI 6221.  i decided to feed the signal directly to DAQ, can u tell me is there any amplifier for the amplification of Direct EMG signal. I am searching for it but could not find. pls tell me soon as it is urgent.

[NI-Bongo]

Hi kapillohia,

You can configure the PCI-6221 to operate in the +/-0.2V range via the DAQ Assistant or other example program.  This range provides an absolute accuracy of 112 uV and a sensitivity of 5.2 uV.  My understanding is that the approximate range for EKG signals is 0.1-5 mV or so.  You should be able to see these signals by setting the input range as stated above.

The instrument amplifier in the PCI-6221 is automatically reconfigured when you set the input range.  You should not need an external amplifier with this device unless you require better resolution than the 5.2uV stated above.  Let us know if you need further help.

Getting Started with NI-DAQmx
http://zone.ni.com/devzone/cda/tut/p/id/5434