I have finally gotten around to re-writing some of my old code and re-recording a proper demo of controlling physical objects using thoughts by interfacing an EEG headset with an Arduino. While this technology is interesting and exciting, before anyone sees this as an endorsement for this particular EEG headset, I strongly recommend reading my full review of the device below. Those of you who have no interest in purchasing such a device can simply enjoy the show :D.
Basic EEG Concepts:
Note: if you’re already familiar with EEG I recommend skipping this paragraph and going straight to the video.
From Wikipedia: “Electroencephalography (EEG) is the recording of electrical activity along the scalp produced by the firing of neurons within the brain.” In medical applications EEG is used to detect conditions such as epilepsy by recording and observing electrical activity from the brain that travels along the scalp. In reality what we’re dealing with are a bunch of ADCs connected to electrodes attached to the scalp that are able to detect minute electrical signals and process them in such a way that they can be analysed. The EEG headset used in this project is NOT a medical device, nor is it suitable for such medical diagnoses.
Emotiv EPOC Headset Review:
Please note that this review is strictly based on my experiences, observations and opinions of the device and should not be taken as gospel. If you’re curious about the device I suggest researching it on your own and comparing my review to what other people are saying about it.
My obsession with the Emotiv EPOC headset began when I saw an episode of Discovery Channel’s TV show “Prototype This” starring Joe Grand and Dr. Andrew “Zoz” Brooks who are teamed up with a few other people to create awesome prototypes and show the process. In the episode the guys used the Emotiv EPOC headset in order to control a vehicle’s transmission to shift from neutral to drive as part of an overall system that would use bio-feedback to slow/shut down a car’s engine if the driver who was remotely controlling the vehicle experienced “road rage.” I can’t say enough good things about this TV show and was extremely disappointed to hear that Discovery not only cancelled the show, but sold off everything in the warehouse incl. the projects for dirt cheap, but that’s another story. The episode had me so excited about the possibility of controlling physical objects with thought alone that I looked up the company who made the device, which was not actually in production as of that time. I was still so psyched that I pre-ordered the $500 developer edition headset so that I’d be one of the first people to be able to get a crack at playing with this thing.
Fast forward several months to July 2009
Defcon 17, Las Vegas 2009
While helping a friend work on his badge hack in the Hardware Hacking Village at Defcon 17 I saw Zoz standing around and couldn’t pass up the opportunity to pick his brain. Among other things, I had asked him for his opinion on the Emotiv EPOC headset after I had told him that I pre-ordered one. After a slight pause he simply replied “It did what they said it would do.” This was a somewhat less than enthusiastic response compared to what I was expecting, and I was about to find out why for myself.
Shortly after Defcon I received the headset. The first thing that caught my attention while unpacking it was the container that the felt pads came in. There was a sticker on it that read “WARNING: First off-tool sample. This unit leaks slightly. Use upright only. It will be replaced when the tooling is properly adjusted.” I should also point out that I initially received the headset in early Oct 2009, and as of today, nearly 7 months later I *STILL* have yet to receive a replacement. The next thing I found disturbing was that the “tentacles” on the headset would actually split apart slightly exposing the wires underneath. I posted my concerns on the forums and was told that it was due to a manufacturing error, that the pieces were simply cut a bit too long. The post from the company on the forum actually suggested that a possible solution was to cut each of them and glue them in place but to be careful not to nick any of the wires while doing so as it would void the warranty. (sarcasm)Pro.(/sarcasm)
Despite all of this I was still excited to get it up and running. Since I’m already discussing the “Cons” of the product I will continue and talk about the “Pros” at the end of my rant :D. There are several restrictions that I knew about and willingly accepted when I purchased the headset, but I was hoping to overcome some of them with a bit of effort. In particular, the SDK only works in Windows and the licensing agreement restricts you to only being able to distribute applications you create (whether you want to charge for them or offer them for free) through Emotiv’s own online store. You also do NOT get access to raw EEG data with this license, in order to get that I would have had to have spent $75,000 at the time I placed my order. That price was later reduced to $7500. Around this time I had gotten some apps written and working using the API as well as a wrapper written by “the0nex” to let me use the API in C#, but I was frustrated with the fact that I had to use their USB dongle to receive the signal which needed not only the cost of a PC but also the cost of a Windows license to run any embedded project. Shortly thereafter, somebody posted pics of a teardown that he had done of the headset. I recognized the wireless communications chip immediately as I had worked with it before. It uses the NRF24L01. Having previously worked with this chip I was confident that I would be able to create my own embedded receiver and hopefully get a very limited embedded version working that didn’t require super expensive equipment. Even if it only detected one cognitive thought or facial expression or whatever, at least it was something. After doing some tinkering with the USB dongle to analyse the data coming from it, it was revealed to us on the forums that the data transmitted from the headset was encrypted and relied on the library and PC processing power to decrypt and analyse it. So… if you’re thinking of purchasing this product be fully aware that you will need a Windows PC in order to do anything at all with it. There is also a hard-coded limit of up to 4 simultaneous actions that it can detect, but I have had problems getting it working reliably with more than 2. I’m not alone here, and this has been debated on Facebook as well as their forums. The company states that they have had a scientist successfully make use of 8 “cognitiv” functions at a time, but no supporting documentation or any details were given. People in forums (who didn’t actually own the product) were saying that it was because it requires significant training to get your brain to be able to produce these different states. Of course both of these claims are entirely possible/probable, all I can tell you is that I have personally never gotten it to reliably (ie: 90%+ success rate) gotten it to detect 3 distinct states without mixing them up and everybody else I have personally spoken to has reported similar results. As I posted my growing frustration on the forums I was sent a personal message offering me a free upgrade to the raw EEG data license on condition that I never speak of it. I wrote back stating that this was not what I was looking for, but if they were going to offer it I’d certainly accept and play with it. I went on to explain that what I was REALLY interested in was some kind of embedded solution that could run without a Windows box (or even libraries that would run under linux since some relatively inexpensive micros can run linux distros, and I get to save a few hundred on the Windows license). I can only assume that I’m not the only person this offer was made to, but even after telling them that I’d check it out, I never heard back from them again. Shortly after this the (originally $75,000) raw EEG license was dropped to $750. I’m guessing this indicates that there was either a huge problem with their business model, or their market research.
One more quick thing: The felt pads that go on the sensors do get dirty and nasty after a while. I’ve been cleaning mine in isopropyl alcohol, which has kept them in relatively good condition. Others have not been so lucky. People (almost since day 1) were posting on forums that they wanted replacement felt pads. Some had been dropped and stepped on accidentally, some were attacked by the owner’s cat and chewed up, etc etc etc. The company, which at the time was struggling just to fill the pre-orders it had, stated that once pre-orders were filled replacement pads and holders would come on sale inexpensively. They finally did months later for a mere $50. That’s 10% of the cost of the developer headset and 17% of the cost of the regular consumer headset for roughly $1 in felt and $5 in molded plastic with little metal discs to make contact.
Enough about the bad… now on to the good…
When I try to think of the best way to describe the qualities of this device the phrase that pops in to my head now is “It does what they said it would do.” Plain and simple. I’m not trying to say that this is a bad device, but I strongly encourage people who are considering a purchase to look into it. If you are fully educated about what it can/can’t do, you are at least able to make an informed decision before spending your money. Don’t just take my word for it, read their forums, read reviews, read anything you can about it. As I mentioned above, it has been 7+ months since the initial shipment of headsets and to this date there are only 6 applications total listed in the website’s store, including the demo game and console app released by Emotiv themselves. I think this speaks volumes as to how people have received this product. Personally I gave up on participating in their forums months ago and have since been looking into opensource EEG platforms. There are currently a few out there, and there is some pretty awesome and powerful opensource software available for Linux for processing this data. I believe that this technology can be amazing when used in accessibility applications. Wheelchairs, robotic arms, and an array of any product you can imagine controlled by thought are the direction I had hoped to go in, but having to physically strap a laptop and monetarily strap the hardware and license costs on is disgustingly restrictive. One of my projects lined up for the future is to expand on one of the opensource platforms to increase the number of sensors to match, if not beat, the number of sensors that the EPOC has, as well as to position/configure them in a way that actually matches accepted industry standards and to start playing with that. Afterall… “if you can’t open it, you don’t own it.”
That being said, I have to give credit where credit is due. The company never claimed that I would be able to use the device in the manner which I had hoped. Their primary target market is the video game industry. The headset is intended to add a dimension to games in that it can actively monitor a user’s excitement/boredom in order to change the flow of a game to keep it fresh from the user’s perspective. Personally, I think that if a game has to actively monitor a player’s boredom levels there is probably something seriously wrong with it. I think that a much better use would be to hook users up for focus-groups and closed testing of games before they are released and record boredom levels as the user plays and tweak the game before it gets released instead of real-time as a user is playing, but if I knew everything I’d be rich instead of making projects in my workshop :D. Other things that work really well on the headset are the facial expression recognition features and gyro. The headset can detect clenched jaw, smile, raised/furrowed eyebrows, eye direction, blinks/winks/etc. and does a really good job of it. As far as competition goes, I looked at similar commercial products at the time I made my purchase and, frankly, the Emotiv EPOC blows them all out of the water. More features, more electrodes, more detections… the EPOC wins hands down! Reading back I realize that my critique may have been a bit harsh, but it’s only because I had such high hopes for this headset when I bought it. As I said, it does what they said it would.
**UPDATE** I have already received Emails in regards to this post and it seems that Emotiv has completely changed over their forums and moved the old forums (which were basically strictly developers participating in them since it was from before the consumer version was available). I’m guessing that this is where the most critical posts were because, Emotiv says that it’s still up @ http://www.emotiv.com/oldforum but unless I’m logged in I get a 403 Error. I don’t know if all logins will have access or if it’s only developers, but that’s where any discussions I would have been part of are located.