search

openyou / emokit

Open source driver for accessing raw data from the Emotiv EPOC EEG headset
http://www.openyou.org
Other
523 stars 236 forks source link

Contact Quality values always 0 #135

Closed saatvikshah closed 7 years ago

saatvikshah commented 9 years ago

My contact quality values always show the value 0. What could the possible problem be?

ghost commented 9 years ago

Reference sensors aren't making good contact?

From: Saatvik Shah notifications@github.com<mailto:notifications@github.com> Reply-To: openyou/emokit reply@reply.github.com<mailto:reply@reply.github.com> Date: Saturday, November 15, 2014 at 12:15 PM To: openyou/emokit emokit@noreply.github.com<mailto:emokit@noreply.github.com> Subject: [emokit] Contact Quality values always 0 (#135)

My contact quality values always show the value 0. What could the possible problem be?

Reply to this email directly or view it on GitHubhttps://github.com/openyou/emokit/issues/135.

saatvikshah commented 9 years ago

Following your response I prepared the headset correctly,applied the gel and tested by wearing it. I am getting almost all sensors showing green in the Epoc Control Panel. My readings from Emokit are as follows Y Reading: 3 Quality: 0 F3 Reading: 370 Quality: 0 F4 Reading: 513 Quality: 4 P7 Reading: 1120 Quality: 0 FC6 Reading: -627 Quality: 9 F7 Reading: 858 Quality: 0 F8 Reading: 1746 Quality: 0 T7 Reading: 611 Quality: 0 P8 Reading: -11 Quality: 0 FC5 Reading: 698 Quality: 0 AF4 Reading: 1308 Quality: 0 Unknown Reading: 37 Quality: 0 T8 Reading: 642 Quality: 0 X Reading: -8 Quality: 0 O2 Reading: 381 Quality: 0 O1 Reading: 321 Quality: 0 AF3 Reading: -300 Quality: 11 Battery: 66 Additionally attaching a screenshot of the Emotiv Control Panel emotiv Is there any cause for concern?Why are few values for quality proper while others still giving 0? Ive tested this on Ubuntu 14.04

ghost commented 9 years ago

Are you using the latest version?

From: Saatvik Shah notifications@github.com<mailto:notifications@github.com> Reply-To: openyou/emokit reply@reply.github.com<mailto:reply@reply.github.com> Date: Sunday, November 16, 2014 at 12:27 PM To: openyou/emokit emokit@noreply.github.com<mailto:emokit@noreply.github.com> Cc: William Schumacher bill@servernet.co<mailto:bill@servernet.co> Subject: Re: [emokit] Contact Quality values always 0 (#135)

Following your response I prepared the headset correctly,applied the gel and tested by wearing it. I am getting almost all sensors showing green in the Epoc Control Panel. My readings from Emokit are as follows

Y Reading: 3 Quality: 0 F3 Reading: 370 Quality: 0 F4 Reading: 513 Quality: 4 P7 Reading: 1120 Quality: 0 FC6 Reading: -627 Quality: 9 F7 Reading: 858 Quality: 0 F8 Reading: 1746 Quality: 0 T7 Reading: 611 Quality: 0 P8 Reading: -11 Quality: 0 FC5 Reading: 698 Quality: 0 AF4 Reading: 1308 Quality: 0 Unknown Reading: 37 Quality: 0 T8 Reading: 642 Quality: 0 X Reading: -8 Quality: 0 O2 Reading: 381 Quality: 0 O1 Reading: 321 Quality: 0 AF3 Reading: -300 Quality: 11 Battery: 66

Additionally attaching a screenshot of the Emotiv Control Panel [emotiv]https://cloud.githubusercontent.com/assets/6854735/5062611/1c6b9912-6dec-11e4-8aba-c41efc17068f.png Is there any cause for concern?Why are few values showing a proper value for quality while others still giving 0?

Reply to this email directly or view it on GitHubhttps://github.com/openyou/emokit/issues/135#issuecomment-63231402.

saatvikshah commented 9 years ago

No, Im using an Emotiv EPOC headset which is around a year and a half old. However Im using only a month old sensors.

On Fri, Nov 21, 2014 at 1:18 AM, William Schumacher < notifications@github.com> wrote:

Are you using the latest version?

From: Saatvik Shah <notifications@github.com<mailto: notifications@github.com>> Reply-To: openyou/emokit <reply@reply.github.com<mailto: reply@reply.github.com>> Date: Sunday, November 16, 2014 at 12:27 PM To: openyou/emokit <emokit@noreply.github.com<mailto: emokit@noreply.github.com>> Cc: William Schumacher bill@servernet.co<mailto:bill@servernet.co> Subject: Re: [emokit] Contact Quality values always 0 (#135)

Following your response I prepared the headset correctly,applied the gel and tested by wearing it. I am getting almost all sensors showing green in the Epoc Control Panel. My readings from Emokit are as follows

Y Reading: 3 Quality: 0 F3 Reading: 370 Quality: 0 F4 Reading: 513 Quality: 4 P7 Reading: 1120 Quality: 0 FC6 Reading: -627 Quality: 9 F7 Reading: 858 Quality: 0 F8 Reading: 1746 Quality: 0 T7 Reading: 611 Quality: 0 P8 Reading: -11 Quality: 0 FC5 Reading: 698 Quality: 0 AF4 Reading: 1308 Quality: 0 Unknown Reading: 37 Quality: 0 T8 Reading: 642 Quality: 0 X Reading: -8 Quality: 0 O2 Reading: 381 Quality: 0 O1 Reading: 321 Quality: 0 AF3 Reading: -300 Quality: 11 Battery: 66

Additionally attaching a screenshot of the Emotiv Control Panel [emotiv]< https://cloud.githubusercontent.com/assets/6854735/5062611/1c6b9912-6dec-11e4-8aba-c41efc17068f.png>

Is there any cause for concern?Why are few values showing a proper value for quality while others still giving 0?

Reply to this email directly or view it on GitHub< https://github.com/openyou/emokit/issues/135#issuecomment-63231402>.

— Reply to this email directly or view it on GitHub https://github.com/openyou/emokit/issues/135#issuecomment-63867778.

Saatvik Shah, 3rd Year, Computer Engineering, NIT Jaipur

mnzab commented 9 years ago

I m having the same problem. Contact quality is showing 0 for all sensors all the time. @saatvikshah1994 , Were you able to resolve the issue?

ahmedfarazkhan commented 8 years ago

@saatvikshah1994 and @mnzab, did you manage to resolve your contact quality issues?

saatvikshah commented 8 years ago

Nope I wasnt able to resolve the issue - But my Emotiv headset was a bit old and not very well maintained. That could have also been the issue.

nathanielatom commented 8 years ago

I tried storing the quality values as floats instead of ints (currently the code uses integer division). This gives non-zero values - mostly ~0.02 - when there are no electrodes connected. Shorting a channel to ground seems to produce a higher quality as does pressing an electrode against skin. I made a pull request #158 that includes this change.

ghost commented 7 years ago

Changed the defaults to not be a small integer and instead using a utility function to check the signal level, so now there should definitely be something other than 0 if it's on your head.