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Hello! A lot of people have written us saying they are building a Brain-Controlled Wheelchair, and that's great! We look forward to helping you get through the hard parts, but some of you won't need any help (maybe). What we want from you (all of you) are pictures! Or at least a message saying "Hey, we're doing it and we're in (location)" so we can get all excited.
Thank you and Good Luck!
This Instructable will show how to make a Brain-Controlled Electric Wheelchair, so that a person can become mobile without moving their body.
This could be useful for people who are paralysed, and are unable to control parts of their body enough to physically activate the joystick of an electric wheelchair. Many people may be able to use this technology to gain some independence, and to take a break from needing an attendant to push their wheelchair so they can get some fresh air.
The parts of this system include an electric wheelchair, a laptop computer, an Arduino, an interface circuit, an EEG headset, and a collection of ready-made and custom software.
The software which was written specifically for this project (including the GUI and Arduino sketch) has been bundled with Puzzlebox Brainstorms, and is released freely under an Open Source license.
The EEG headset, which connects wirelessly to the laptop, allows the operator to simply think "forward" or "left" or "right" to cause the wheelchair to move. Performance is related to practice by the user, proper configuration of the software, and good contact made by the EEG electrodes on the scalp of the operator.
The interface circuit connects between the Arduino's digital pins and the joystick of the wheelchair. When the Arduino receives a command from the computer, it causes the circuit to "fool" the wheelchair into thinking that the operator has moved the joystick.
WARNING: Electric wheelchairs are designed for trained operators who have practised manoeuvring safely. Electric wheelchairs can weigh upwards of 200 pounds EMPTY! They have no mechanism to stop when they hit a human or an animal, or go off a curb or down stairs or right through a bannister. Make sure no one is in the path of a wheelchair which is not being operated by a human who can operate the OFF switch. Make sure everyone in the vicinity of this Instructable realizes what may happen if they don't get out of the way.
Do not attempt to stop an electric wheelchair with your body.
Thank you and Good Luck!
This Instructable will show how to make a Brain-Controlled Electric Wheelchair, so that a person can become mobile without moving their body.
This could be useful for people who are paralysed, and are unable to control parts of their body enough to physically activate the joystick of an electric wheelchair. Many people may be able to use this technology to gain some independence, and to take a break from needing an attendant to push their wheelchair so they can get some fresh air.
The parts of this system include an electric wheelchair, a laptop computer, an Arduino, an interface circuit, an EEG headset, and a collection of ready-made and custom software.
The software which was written specifically for this project (including the GUI and Arduino sketch) has been bundled with Puzzlebox Brainstorms, and is released freely under an Open Source license.
The EEG headset, which connects wirelessly to the laptop, allows the operator to simply think "forward" or "left" or "right" to cause the wheelchair to move. Performance is related to practice by the user, proper configuration of the software, and good contact made by the EEG electrodes on the scalp of the operator.
The interface circuit connects between the Arduino's digital pins and the joystick of the wheelchair. When the Arduino receives a command from the computer, it causes the circuit to "fool" the wheelchair into thinking that the operator has moved the joystick.
WARNING: Electric wheelchairs are designed for trained operators who have practised manoeuvring safely. Electric wheelchairs can weigh upwards of 200 pounds EMPTY! They have no mechanism to stop when they hit a human or an animal, or go off a curb or down stairs or right through a bannister. Make sure no one is in the path of a wheelchair which is not being operated by a human who can operate the OFF switch. Make sure everyone in the vicinity of this Instructable realizes what may happen if they don't get out of the way.
Do not attempt to stop an electric wheelchair with your body.
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Signing UpStep 1Acquire materials
To build this Instructable, you will need an electric wheelchair, (We used an Action Arrow Storm Series), an EEG Headset, (We used an Emotiv wireless headset), a Laptop Computer, an Arduino, and an interface circuit made from basic electronics, (see step 5 for materials for the interface circuit).
The Electric Wheelchair was acquired as an unwanted extra from a local repair shop. It was not considered serviceable for disabled persons because its condition was below standard. If you hear of someone in need of an electric wheelchair who is low on funds, encourage them to ask repair shops for unwanted chairs.
The EEG Headset is an EPOC acquired from Emotiv. Their site is here:
http://www.emotiv.com/
The Laptop Computer was Steve's but any laptop will do, it only needs to have two USB ports - one to connect to the Arduino, and the other for the EEG headset's Wireless receiver.
An Arduino is a small microcontroller platform with a USB serial interface. In this case, it serves as a bridge between the laptop computer and the interface circuit (see steps 5 and 6).
Originally, the Arduino was not used, and the interface circuit was connected directly to the parallel port of the computer. The computer we eventually used does not have a parallel port, so the Arduino performs the function of providing eight on/off signals based on a packet of serial data sent through its USB interface. So if your laptop has a parallel port but is new enough to run the Emotiv software, you might be able to skip the Arduino.
The Electric Wheelchair was acquired as an unwanted extra from a local repair shop. It was not considered serviceable for disabled persons because its condition was below standard. If you hear of someone in need of an electric wheelchair who is low on funds, encourage them to ask repair shops for unwanted chairs.
The EEG Headset is an EPOC acquired from Emotiv. Their site is here:
http://www.emotiv.com/
The Laptop Computer was Steve's but any laptop will do, it only needs to have two USB ports - one to connect to the Arduino, and the other for the EEG headset's Wireless receiver.
An Arduino is a small microcontroller platform with a USB serial interface. In this case, it serves as a bridge between the laptop computer and the interface circuit (see steps 5 and 6).
Originally, the Arduino was not used, and the interface circuit was connected directly to the parallel port of the computer. The computer we eventually used does not have a parallel port, so the Arduino performs the function of providing eight on/off signals based on a packet of serial data sent through its USB interface. So if your laptop has a parallel port but is new enough to run the Emotiv software, you might be able to skip the Arduino.
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One question though, I looked at Emotiv's website, and there are 2 types of EEG headsets, one is for consumer use ($299), and another one is for developer ($500). So which one are you using for this project?
We did use a "research" version of the Emotiv headset (one step above the "developer") but because we only used the Emotiv Control Panel and EmoKey utilities to interface with our own software there's no reason why you couldn't reproduce our results with just the $299 "consumer" headset.
Incidentally, if you only wanted to control forward movement, you could get away with a NeuroSky MindWave which retails for $99 as there is also support for this hardware in Puzzlebox Brainstorms. The latest release allows "blink control" to select which direction a robot might be steered so we could do something similar for the wheelchair - that is to say, mental concentration would move the wheelchair forward, and blinking several times in a row rapidly would cycle the "forward" direction between left, right, or reverse.
If you want finer levels of control however (it is difficult to start and stop "concentrating" on demand) you will probably want to stick with the Emotiv headset.
Cheers
Steve Castellott
Thank you for this great product.
You can find source code for Puzzlebox Brainstorms talking to our wheelchair's controller in the following two files:
Wheelchair_Control.py
puzzlebox_brainstorms_wheelchair_noisebridge.pde
Our code was specific to our controller, but a similar technique to the one we used might be possible for you. I couldn't really say in more detail without knowing the specifics of your hardware.
EmoKey is a program included by Emotiv with their EEG headset, or can be downloaded for free as part their "SDK Lite" package. It will you to declare a direction or detection you want to look for (such as "Left") and assign that to a keyboard keystroke (such as the Left Arrow key). A good way to test EmoKey is to assign letters of the alphabet to each direction and then load and place Notepad in the foreground. It should print out keys when they are detected. You can use "w" "a" "s" and "d" to mean "Forward" "Left" "Backwards" and "Right" and those keys will work with Brainstorms as well.
Finally that said Puzzlebox is preparing to release an updated version of Puzzlebox Synapse which supports the Emotiv headset and eventually you will be able match detections there directly.
Cheers
Steve Castellotti
Plese let me know your advices.
i started working on this project recently
your website is really of great help!!
the thing is that we are trying to develop a more economic design for the indian users, all i want to know is that what are the changes we need to make with respect to your model if we use conventional eeg electrodes
lots of thanks !!
I do not know if the Emotiv software works with other hardware. Do you have anything specific in mind/
what do you think? you can even suggest an corrections
thanks!
The main differences is that you will need at least 30 min for cap preparation (electrolyte gel, check impedances etc).
But you are wise to avoid Emotiv caps wich are made with dry electrodes, have incomplete cortex coverage. It records very well muscles artifacts, but it can hopefully process P300.
Then you can find free software solutions with OpenViBE if you have the appropriated drivers.
You need to know what paradigm you want to use and how many degrees of control you want to have.
Emotiv software is very good at training at least one direction direction for control [...]. However it seems that most if not all users have trouble training a second or third direction.[...] For this reason it is recommended when first using the software to "cheat" for left and right control by using facial muscles
I want to know which type of EMOTIV headset is suitable for this project & what is cost of the headset.
There were definitely no incidents of the chair moving when the driver did not want it to, except maybe for one second or less.
well practice is needed to drive even with a joystick, so is it good to implement to regular use or should wait for more improvements to happen? and how does the headset responds in controlling the wheelchair? hope you don't mind with my barrage of my questions..i myself drive a wheelchair so wanted to try this out
http://brainstorms.puzzlebox.info/tracker/browser/trunk/brainstorms/emokey/puzzlebox_brainstorms-wheelchair.ekm
Cheers
http://www.ted.com/talks/tan_le_a_headset_that_reads_your_brainwaves.html
"In our experience the Emotiv software is very good at training at least one direction direction for control, for example thinking "Push" to drive the wheelchair forward, and allowing that user to "turn on" or "turn off" that single command at will. However it seems that most if not all users have trouble training a second or third direction as effectively as the first. For this reason it is recommended when first using the software to "cheat" for left and right control by using facial muscles (which is technically EMG, not EEG) for example closing one eye to move left or right or clenching either side of the jaw."
So while yes, the software will allow you to train multiple detections (actually I think you might be limited to four) which can each be used to control a different motion for driving the wheelchair or even a separate device, in reality one shouldn't expect "unlimited thought control" with current consumer-grade technology.
Now that said there have been some incredible advances in the field of BCI research (including a paradigm which allows six-direction detection for fully 3D cursor control) but the physical location of the sensors has to be precise (specifically C3, Cz, and C4 according to the 10-20 system, check Wikipedia for details) and the layout of the Emotiv and Neurosky EEG headsets simply do not provide electrodes in those locations.
This is a very exciting field of technology which is advancing quickly, but for the moment we feel it is very important to make sure expectations are being set which match the true current state of the art.
Cheers
Steve Castellotti
what I typed was:
"
shhhhh... don't ruin the semi-truthful fantasy!
"
"fire slingshot"
"cook meal"
"dig"
You would just need to teach the program how you think each thing by example and then program the bot/buggy/whatever to do what that command implies, such as digging a hole.
You could probably take an exoskeleton (such as Ironman) and teach it what you think for pretending each muscle movement on your body... I'm kind of doubtful that you just happen to have just one sitting around though- 'Oh yea, I got one in 03 for Easter!'