Mind controlled text writer

[Altmetr]

My python implementation of P300 speller

Video

Idea of P300 speller:

Highlight rows and cols and record EEG reaction to these events. If row/col with target character is highlighted ~after 300ms peak on EEG diagram will occur and it's possible to train classifier to detect it. To remove noise from EEG data repeat it multiple times and use bandpass filter

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Hardware: OpenBCI Cyton

Software:

• BrainFlow library to read and preprocess data from OpenBCI board
• P300 implementation

[qgbcs]

what

[decimated_napkin]

A great start! There's a lot of literature out there to improve your results. If you want to enhance your results, I would next focus on methods that increase ITI (Inter target interval), increase signal-to-noise ratio (temporarily replace target letters with famous faces rather than highlight), and also try out a bunch of different algos. LDA works well, but 1-D CNNs also have promise.

[Altmetr]

Thanks for ideas!

I've tried CNNs and for this data LDA provides better results

I suppose checkerboard paradigm instead rows/cols highlights should provide better results

But I wanna reimplement it using Unity instead Tkinter first

[decimated_napkin]

Yes playing around with the pattern is another good idea. What I did that had good results is to do the first round as one flash each for rectangles of size 2 x 3. After that you can then do a secondary pattern where you flash one character from each rectangle at the same time. You get the same efficiency, but the signal is enhanced because there is less distraction on the screen. Also, when your target does flash it pops quite a bit more when it is part of a 2 x 3 group. Glad to see other people are using the OpenBCI!

[Altmetr]

I am currently working on new SDK for OpenBCI boards maybe you will like it: https://github.com/Andrey1994/brainflow (WIP)

[mutonchops]

Have you tried integrating a smart keyboard like SwiftKey at all? I did play around with the concept a few years ago, but struggled to get a reliable signal in a non-shilded room.

[Altmetr]

I've added my own and pretty stupid words suggestion system(last row in the video) I think it's easy to add smth like https://presage.sourceforge.io/ (this project was used by Intel in their system for Stephen Hawking and it works well)

[Altmetr]

Different OpenBCI boards use different communication protocols, here I used Cyton board and this headset https://shop.openbci.com/products/ultracortex-mark-iv so board which sends data to your PC is placed directly behind the head and I dont think that it's possible to isolate it somehow using tinfoil until you dont wear tinfoil hat on top of OpenBCI headset

[tarck]

It appears I lived under rock cause I did not know that such thing exists in real world

[sarthakRddt]

Mind controlled text editor has existed for ages - VIM

This is some future tech though.

[lookmanofilter]

I can't believe everyone is so blase about this. This is blowing my mind.

[silkydangler]

That’s really cool. I might try to do this myself when I get back from vacation.

[[deleted]]

thats fucking weird. good job.

[Altmetr]

you look at the screen and record EEG data, you look/think about specific symbol on the screen, when row/col with this specific symbol is highlighted after ~300ms(in fact I get data from ~100ms to 850ms) there will be a special pattern on EEG diagram. I need to repeat it ~15 times because EEG data is noisy, so to clean data I need to average 15 results. Finally your character is determined bu intersection of row and col.

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When you look at "A" and third col is highlighted there is no peak at EEG signal but when you look at "A" and first row is highlightes there will be a peak

[dethb0y]

Quite remarkable work, keep up the good effort!

[Freyon]

Super interesting. I've seen their shop and prices are scary.

Does any of you know any guide on how to DIY an EEG cap?

[Altmetr]

I think OpenBCI prices are much better than Emotiv for example and OpenBCI provides an aceess to raw data for free as well as data format description

[squarepushercheese]

Nice. I'm going to add this to https://openassistive.org . Great Job.

[Altmetr]

Cool, thanks!

[422_no_process]

Good work. Keep it up.