OpenViBE Acquisition Server (motor imagery), montage, configuration

Comments

• wjcroft Mount Shasta, CA

  April 2016

  Assuming you've seen Jeremy's @jfrey posts that do mention the Acquisition Server setup,
  
  http://blog.jfrey.info/2015/03/03/openbci-motor-imagery/
  
  http://openbci.com/community/openbci-crossing-swords-with-motor-imagery/
  
  With that @ reference and email notification, Jeremy may comment here. There are also some tip on the AS setup on these threads,
  
  http://openbci.com/forum/index.php?p=/discussion/206/openvibe-p300-speller-tutorial-questions
  
  http://docs.openbci.com/research tools/OpenViBE
  
  http://openbci.com/forum/index.php?p=/discussion/326/openvibe-v1-0-now-supports-openbci
  
  William
  
  
  
  
• sameera

  April 2016

  Thanks @wjcroft. i hope @jfey will see my queries and give advice of how to resolve soon. I am already trying to run the mi-csp scenarios of openvibe on windows 8.1 by following this link: http://openbci.com/community/openbci-crossing-swords-with-motor-imagery/. So i think i need to re-phrase my queries as follows:

  Openvibe is running fine on windows 8.1[as well as windows 7], as tested by running the oscillator and viewing signals in designer. After loading the openbci driver in the acquisition-server of openvibe, i am also able to view the raw signals in mi-csp-1-acquisition.xml.  

  1-After attaching channel-selector box, how to 'remove the faulty channels at the same time you get rid of the accelerometers.''?

  2-Next, the tutorial goes on to say that ''A file with the .ov extension will be created in the signals folder next to the scenarios files.'----the file DOES NOT get saved!!!!What to do?

  
  

  
  

  
  
• wjcroft Mount Shasta, CA

  April 2016

  Hi Sameera, I'm going to re-mention Jeremy @jfrey because you spelled the at-sign name wrong in your last comment. If the username is not spelled correctly, they do not get an email notification.
  
  Did you look at the OpenViBE documentation on the AS?
  
  https://www.google.com/search?q=openvibe+acquisition+server
  
  Wouldn't you just check "Select only named channels"?
  
• sameera

  April 2016

  hi @wjcroft thanks again. I did read the doc on AS before, and again today as u suggested.... and was FINALLY able to save a recorded file in openvibe on windows 8.1 [64-bit]. It was basically a matter of obtaining file-writing/saving permissions in C drive of windows 8.1, where openvibe gets installed by default. [as far as i know, no one on openvibe/openbci forums mention this imp. fact!!!!!!!] Hopefully now i will be able to resolve my first query also by 'selecting only named channels' ........
• Azhar Karachi

  April 2016

  Hi @wjcroft / @jfrey
  
  This is with reference to the post http://openbci.com/community/openbci-crossing-swords-with-motor-imagery.
  
  I have 8 channel OpenBCI V3 board. I wish to implement the motor imagery exercise (Open BCI + Vibe) using this board without daisy chain module. Please guide about the positions of remaining electrodes other than C3 and C4.   
  
  Thanks for your time.
  
  Regards,
  Azhar
  
• Azhar Karachi

  April 2016 edited April 2016

  Hi @wjcroft / @jfrey
  
  This is with reference to the post http://openbci.com/community/openbci-crossing-swords-with-motor-imagery.
  
  I have 8 channel OpenBCI V3 board. I wish to implement the motor imagery exercise (Open BCI + Vibe) using this board without daisy chain module. Please guide about the positions of remaining electrodes other than C3 and C4.   
  
  Thanks for your time.
  
  Regards,
  Azhar
• wjcroft Mount Shasta, CA

  April 2016 edited April 2016

  @Azhar, hi.
  
  Jeremy's @jfrey post does already show two montages, one that requires 16 channels, the other will work with your 8 channel board. He points out that the 16 channel montage is optimal for the resolution that is needed. If you go with less channels on the first setup, you may find it harder to achieve the results.
  
  Have you looked over other possible MI montages?
  
  https://www.google.com/search?q=bci+motor+imagery+montage
  
  
  
  
  [Figure 12. The best configuration with 8 electrodes given by Hoffman et al. (Hoffman et al., 2008), (Hoffman et al., 2009).]
  
  http://www.intechopen.com/books/intelligent-and-biosensors/signal-processing-and-classification-approaches-for-brain-computer-interface
  
  http://infoscience.epfl.ch/record/101093/files/manuscript.pdf
  [section 4.2]
  
  http://sccn.ucsd.edu/~yijun/pdfs/EL07.pdf
  
  
  
• jfrey

  April 2016 edited April 2016

  
  Hi, sorry I will answer in a hurry (...as usual I think if you check my history ):

  
  

  @sameera

  
  

  "remove the faulty channels at the same time you get rid of the accelerometers": I mean that you should select only the channels you need. Use the box named "channel selector", and configure it accordingly. E.g. if you have 4 electrodes only, connected to channels 1 to 4, you put "1:4". 1 to 8 are EEG, 9 to 11 are accelerometers (add +8 if you use daisy channel). Note that the bias and the reference do not appear as recordings, they are used by openbci to compute other values internally.

  
  

  You do not need to name the channels when using CSP, it'll find the best combinations of channels, whatever the actual positions. Although, note that if you use a different *number* of channels you may need to change accordingly other boxes, e.g. the number of input of spacial filters.

  
  

  file permission: you can actually configure the box to select other folders, your home folder instead of the system one where openvibe is installed -- but you're right, the doc should be more explicit. Be also wary of non ascii characters or spaces in the path name, I had troubles in the past because of that -- may be fixed on newer windows / openvibe versions.

  
  

  As for the right montage, @Azhar , ....well, I won't have better advice than William

  
  

  Good luck to both of you with the MI!
• Azhar Karachi

  April 2016

  Thanks.