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OpenBCI_Python output: "$$$daisy removed"

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Hello, 

In Python, when I run the user.py, I type /start for streaming and I get following messages.

No function loaded
% OpenBCI V3 8-16 channel
% On Board ADS1299 Device ID: 0x3E
% On Daisy ADS1299 Device ID: 0x3E
% LIS3DH Device ID: 0x33
% Firmware: v2.0.1
% $$$daisy removed
% $$$updating channel settings to default

It says, daisy removed. I have daisy board. Is it normal?  

Python SDK Test.log.py

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When I execute the test.log.py in python SDK,  no record is saved to test.log; 

Except 

---------LOG START-------------
serial closed

Is it normal?

Thanks,
Sefa


Encoding Data and How to send to list

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I checked to documents in OpenBCI and github and didn't find how to send all data in a list real time. 

Any suggestion or detailed documentation for that?  

Furthermore, I have a encoding problem on character when I want get them on therminal. How can I get over this problem? 


not detecting a 100uV DC signal generator

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Hi, and pleased to meet you all. I have just registered on the forum...
I am using Cyton board and trying to amplify a low DC signal (about 100 microVolts) generated directly from a signal generator.
I have connected the output signal to one of the SNP pin of the OpenBCI board (for example, the n. 2).
Then I have grounded the DC signal generator and the board connecting the ground with the GND pin of the OpenBCI.
I am not seeing any signals on the OpenGUI.
Surely I am getting many thins wrongs...Could you help me in some way?
Thank you to youall in advanced....
G.

Simblee BLE Documentation?

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I am trying to connect to the Simblee BLE module on the Ganglion board from numerous devices. Might there be documentation I can review? I am awash in Simblee versions and don't know the model number. What might my next step be?

Not getting Trigger data using wifi shield connected to Cyton and daisy combination

Research Methodology & Safety

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Hi all,

I am new to this, and think amazing things can be done with this platform. I wanted to ask about your experience and know-how regarding the following:
1. What is the best and safest method to clean the dry electrodes between subjects in the study? (I was thinking - a toothbrush with 70% alcohol - to gently scrub and let alcohol evaporate...)
2. I need to register this device for approval by my local ministry of health (Israel).. So I can use it on subjects in a clinic. Does any of you have similar experience?
3. For the "Methods" section... Is there a pre-made piece of text you are using regarding the Cyton, Daisy and Ultracortex devices, or better yet, a citation I can use when I do the write-up? something official by OpenBCI team that I can also use for internal research comity approval?
4. I want to use a longitudinal bi-polar montage. For this I need a bunch of "Y" cables to connect the electrodes in a serial fashion to the positive & negative pins of the boards, so they form a bipolar chain with each electrode serving (except for the "end-chain" ones) as the negative of one channel and positive of the other... I don't want to make those myself (fearing clumsiness). Do you know where I can get a bunch of Y with one male and 2 female ends?
5. Also, I have a surge of rhythmic artifact on 50Hz and 25Hz ± I can't get rid of... Any idea where they come from? (yes, I am wearing the Ultracortex and I am not touching any surface that has a device connected to the grid [50Hz in israel]).

This is the beginning, many more questions to follow, Thank you all in advance,
SA

Ganglion Input-Referred Noise?

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Hi,

I am interested in using Ganglion or Cyton board to record Auditory Brainstem Response to click stimulus. To determine the feasibility, I need to know the Input-Referred Noise measured when the input is shorted together. For the Cyton board, all is in the ADS1299 datasheet on Table 1 to Table 5.

For the Ganglion board, I found 2 measured values on the forum.

The first one give a value of 1uVpp Input-Referred Noise at Fs=256Hz ("10 Minutes Noise Test Ganglion.txt")

https://github.com/OpenBCI/Ganglion-Prototype-Data

The second one give a value of 10uVpp Input-Referred Noise at Fs=256Hz

http://openbci.com/community/ganglion-review-input-noise-and-p300/

In both measurements, unfortunately the level of PGA gain is not specified... and it's obvious that gain will influence Noise value. Does someone know the value of Input-Referred Noise regarding the sampling frequency and PGA gain ?

Thanks,

Bad fixed artifacts

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Hi all, 

Finished assembling my Cyton+Daisy 16 channel setup. Unfortunately I get this horrible artifacts on all channels (see below). All input electrodes are connected to the low pins. 
Both SRBs are connected via Y cable to left ear and BIAS of Cyton connected to right ear.

What am I doing wrong? (no, Im not touching the table or any other thing while with ultra cortex on). also... it did work somewhat yesterday and i dint change anything.
Any thoughts?

>>> EDIT: I just saw it did not add the image.. don't know how to add it..

The artifact domains are roughly 13-14Hz + ±25Hz & ± 48Hz. Any idea what they are? (I have the 50Hz notch on and those are not harmonics)

collaborate with me on neurofeedback project to train 'Jhana' concentration-meditation states

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Hi there!

My name is Luc, I'm currently studying Human-Computer Interaction (5th semester) in Hamburg. For the past 6 months, I've been spending the majority of my time working on this project.

About the project:

There are deep states of meditation called the Jhanas, that are achieved through means of sustained concentration on an object. Measurements of these states have already been shown

For starters, these states are described as a centering of awareness, where there is a merging between the subject and the object of concentration. They are often described as blissful, and cognitive abilites like focus remain heightened for hours after the meditation session.

The catch is, it takes a long time and a lot of energy to even come close to these states. This is something that people (e.g. monks) devote their lives to. In my own practice, I have found that the biggest roadblock to moving forward in concentration meditation is the fact that I don't know whether or not I am doing it right. I could have spent months meditating every day, and not know whether I have gotten better or not. 

That's where the project starts. I am using an OpenBCI in order to measure my brainwaves, and writing a game that will do complex signal processing and machine learning to steer the subject in the right direction while meditating.
The idea is the creation of a positive feedback loop, as well as session tracking, the same way a powerlifter would track all of his variables in order to lift the highest amount of weight. 

My biggest hope would be to have a system that can accurately measure the depth and duration of the concentration, in order to accelerate the process of attaining access concentration and/or jhanas. EEGs are limited in spatial resolution but have excellent temporal resolution, and we don't know the upper limits of machine learning.

If something like this works, it could increase the focus of serious practitioners in a way that no other practice would allow. 

What I've already made:

I have made a first Unity project that tracks simple parameters like band power and site coherence, and recorded lots of sessions including control sessions. I managed to determine some kind of difference between a control session and a meditation session, but this was not enough for Neurofeedback purposes. I've also got data visualization of all the parameters. 

First prototypes of the "gamified" trainer exist, but are very rudimentary. 

What I'm planning to do:

I want to delve into deeper methods of analysis, these include, but are not limited to:

  • Microstate analysis
  • Wavelet Packet Decomposition
  • Fractal Dimension of the Signal
  • Other Machine Learning methods

I also want to work on the following things:

  • Gamification (Achievements, levels, scores, leaderboards)
  • High quality Data visualization (the brain is an aesthetic thing to track)

Who I need

For now, I mostly need people that are motivated to join in on the analysis. I don't care too much about your current skill, much rather about how motivated and enthusiastic you are. If you can invest 10hrs+ a week, we could already make something happen. 

This is a project that fascinates me to no end, but I couldn't find people that would be interested in joining in. Now is the perfect time, as I am restarting the project in a clean an organized manner.

Of course, this is a very limited description of the project, but if that has sparked your interest, we could talk more about it over Skype!

Cheers,

Luc

CSV data files contain only bursts of data, not continous streaming

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I
have the Mark IV headset with the Cyton 8-channel board connecting via
the Cyton bluetooth. I use the stand-alone GUI application v3.0.1.
Windows 10 on a fairly high-end PC.

I
am trying to get started with recording data. The GUI is set to 250 Hz.

I see csv data files being created in the
"SavedData" folder. However, when inspect them it seems the data is transmitted only in "bursts". A burst
lasts about 4 milliseconds. During that time period I get 3-5 rows each millisecond (as read from the time stamp), so all in all there are about 12-20 rows.  Then there is NO data for about 0.47
seconds, followed by a second similar burst, followed by another 0.47 second gap. This pattern repeats. Why isn't it there a continuous streaming? Shouldn't a sample 250 Hz imply that I get precisely 1 row every 4 millisecond? I am not very savvy with electronics so perhaps I am missing something basic here.

Higher sample rates / sample at 2000hz to SDcard?

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So... i am aware that the higher sample rate discussion has already been mentioned in a few threads, and i am sorry if this all should be obvious to me.

I do really wonder though, whether it would not be possible to drastically increase the sample rate, if one chose to only use one or two channels?
And if so, how would one go about telling the ADS1299, to only process data from channel 1 and 2 ?


Possible to start writing to SD card automatically when powering on board?

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How difficult would it be to program the Cyton to start writing directly to the SD card when you power on the board instead of having to interface with the computer, and to have the LED flash indicating that it is successfully recording data?

For example, if the daisy module is not attached it would automatically record 8ch data and if the daisy module is attached it would automatically record 16ch data.

This would greatly increase the ease of use for larger ambulatory studies.

Ganglion: Detecting other brainwaves other than alpha

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Greetings!

Is it possible to detect ERP's or Mu Rhythms reliably with a Ganglion?

Thank you in advance!

Crazy Arduino Trigger Signal

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I would like to record some events triggered with an Arduino Leonardo.  Below is a Ganglion produced record of the reduced triggering signal.  The signal, high for one second and low for two seconds, has been reduced to 5 mV with a simple voltage divider (R1=10kΩ R2=10Ω).  Why does this signal look so crazy?


https://photos.app.goo.gl/HNoyQKXimeY8CYZb2


MATLAB OpenBCI documentation - hyperlink broken on channel locations

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Hi,

The link to the channel location files (sfp) does not work.  I cannot download the location files, so I cannot finish importing my files into MATLAB.

Thanks,
Don

Which electrode to reference when importing data into EEGLAB

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Hi,

I am not clear on which electrode to reference when importing data into EEGLAB.  On the EEGLAB Pre-processing Tools webpage I read:

Systems with active electrodes (e.g. BIOSEMI Active Two), may record
data reference-free. In this case, a reference be must be chosen post hoc during data import. Failing to do so will leave 40 dB of unnecessary noise in the data!


I don't want to lose the signal quality.  I believe OpenBCI uses Active Electrodes, but do not know which to choose during an import?  Which one is best suited?  All of the other electrode signals will reference the one.  I don't understand how this does not skew results?

Thanks,
Don

Uploading Electrode Location Information to EEGLAB

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Hi, I am having trouble uploading the channel location of the electrodes onto EEGLAB. I am using a TI-ADS1299-EEGFE-PDK and I converted my data into .txt files, but the channel location does not get added to the data. Does anyone know how to add this information in, or how to create a separate file with the channel location data to upload it? Thanks!

Repair for Snapped Electrode Wire

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A few of the electrode wires on our Mark IV headset have snapped off where the wire meets the crimp (see photo below).  We think this was caused from twisting in the electrode while the wire was connected, and will avoid doing this in the future.  My question is, has anyone had this happen before, and how did you fix it? I could solder the wire to the crimp but I'm not sure how durable that would be.  Any suggestions?

Thanks!

image

Android Tablet connect Ganglion via own app HOW??

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Hey guys!

First Problem: My Android Tablet (Huawei) does NOT find the Ganglion Board in the bluetooth settings when I search for it. How is it possible to make the board visible and connect directly from the bluetooth settings?
OpenBCI´s tutorial to this is connecting the tablet via the nrfConnect app, which works fine - I would like to connect it through the bluetooth settings on the tablet.

Second Problem: I want to connect the tablet with the ganglion board via an app I found on Github (Link: https://github.com/yeah-sir/OpenBCI-AndroidApp/blob/master/README.md). What code do I need to look for the ganglion board and to connect to it from this app?

I´m very new to this and I´m happy with every help! 
Hopefully you guys can help me - even if it is just a little bit of help!

Thank you! 
Manuel
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