RaspberryPi Powered Wearable Computer

I have been interested in wearable computing for a while.  Until the RaspberryPi was released, there was no affordable and compact option for the computer part of a wearable computer.  My original setup used a laptop in a backpack, but that is a little too big to be practical.  I have seen a lot of arduino based wearable electronics, but they are not exactly what I have been looking for - a full power desktop computer that you can carry around at your side and use while walking, standing, sitting, or doing anything else. 

As a linux guy for many years, the RaspberryPi is the perfect solution to my problem, and I'm already comfortable with the OS.  Before you begin, make sure you read through my instructions.  I have updated several sections through the past few months. 

Just so you guys know, this is my first instructable after being a lurker here for almost seven years.  I'm excited.  So, let's begin! 

Step 1: Materials

Here's a complete list of everything that I used, where I bought it, and how much it cost me:

Battery Recharger (came with 4xAA batteries) - $35 at Radioshack
6 xAA Recahrgeable Batteries - $7 at Radioshack
RaspberryPi Model B - $45 including shipping
Soft Cellular Phone Case - $5 at 5 and below.
USB Battery Pack - MintyBoost Kit - $20 - https://www.adafruit.com/products/14
2xAA battery holders - $5
Vuzix Wrap 920 Video Glasses - $200 on Amazon - http://www.amazon.com/Vuzix-329T30011-Corp-Wrap-920/dp/B002SUCMUG/
Mouse/Keyboard - $37 on Amazon - http://www.amazon.com/VisionTek-Candyboard-Mini-Keyboard-Touchpad/dp/B007VMCBN4/
RCA Coupler - $4 at Radioshack
Micro-USB Cable - Already had
Wireless Adapter - $15 - www.amazon.com/Edimax-EW-7811Un-Wireless-Adapter-Wizard/dp/B005CLMJLU
SD Card - $9 at Microcenter

TOTAL COST: $382

As with any project, you will need some basic household tools.  And some bits of wire.  As for the cost, you should expect to spend around $400 for everything you need.  Fortunately, half of the cost goes into the video glasses.  Otherwise, a laptop would be a better option.  Keep in mind that the computer part is $35 (without shipping)

Step 2: RaspberryPi Configuration

So you have a RaspberryPi.  I'm not going to cover software installation and basic setup, because there are already some great tutorials out there.  Here are some helpful links for that step:

http://www.raspberrypi.org/downloads
http://elinux.org/RPi_Easy_SD_Card_Setup

I recommend Raspbian, simply because I'm a Debian fan, and Raspbian is Debian, but optimized for the Pi.  If you already have a preferred distribution, great.  Use that. 

One thing that I do not like about the Pi is the lack of a heatsink over the CPU.  I don't care what anyone says about passive cooling, something about a CPU without a heatsink on it really, REALLY bugs me.  So go ahead and slap a tiny heatsink on your Pi's CPU.  I used a RAM heatsink from a pack of a bunch of them that I got at Microcenter.  This is ironic, since the Pi's RAM is on top of the CPU.  Anyway.... some folks are putting heatsinks on other chips, which isn't a bad idea.  I just happen to be bothered by the exposed CPU.  Plus, the heatsink does get hot during operation.  So it's definitely doing something. 

I then connected the WiFi dongle and my keyboard's wireless dongle to the Pi, and put it in the cell phone case.  I rested the Pi on a part of an anti-static bag, just to avoid shorting anything out. 

NEW 11 March 2013: I'm now using a 3D printed case for it.  The cell phone case offers the same features, but this printed case is a part of my transition to a slimmer and even more portable version I'm cooking up for the future.  This case is simply thing 33694 from Thingiverse. with a belt clip, thing 39983, hot-glued to the bottom. 

I have also swapped out the blue aluminum heatsink for a copper one, but that's not necessarily any better than the aluminum one since the Pi only produces negligible heat. 

Step 3: Keyboard and Mouse

I bought one of the more affordable miniature keyboard/mouse combos.  I also have a different model with the touchpad on the right side, but I had some problems with that one.  It did not always play nicely with my Pi, and the touchpad on the side hindered my typing. 

This keyboard is really nice for a few reasons.  One is the size.  It's small enough to carry around in your pocket.  It also has a backlight, and is rechargeable.  Did I mention the battery is replaceable?  That's not something you see in portable electronics these days. 

Anyway, make sure you plug the receiver into your Pi, and charge the keyboard for a few hours before using it for the first time. 

Step 4: Power

My power system depends on AA batteries.  Since I do not want to spend countless dollars on batteries, I got six rechargeable batteries and a recharger.  This is pretty simple. 

If you get a MintyBoost as I did, you need to make a simple modification to use it on your RaspberryPi.  The Pi requires more power than just 2xAA batteries alone can provide.  All I did was wire two 2xAA battery packs in parallel before connecting them to the MintyBoost.  I don't have an altoids gum case (yet), so I simply dropped the exposed battery pack and minty boost into an anti-static bag.  Connect a micro-USB cable to the MintyBoost.  Your portable Pi power system is now complete. 

I have not done any tests as to how long the battery pack will actually last, but I speculate that it is within the laptop/netbook battery life range.  Of course, you can use as much or as little power as you want.  It all depends on how much you're willing to carry around with you.  This setup is meant to be super-portable. 

Having 4 batteries is CRITICAL.  I can't stress this enough.  Two batteries will run your RaspberryPi, but it is not enough power to power the keyboard/trackpad and WiFi dongle. 

Step 5: RaspberryPi Configuration

11 March 2013:

I've slightly improved the battery pack.  More Altoids, and more power.  And a power switch now!  Yay!  I managed to stuff the minty boost, a power switch, and four rechargeable batteries into a standard altoids container.  I used two 2xAA batter packs, wired in parallel to achieve the proper voltage.  It's very similar to the last system, but much cleaner looking.  You'll also notice that I have now been tying the battery pack to the Pi case - planning ahead as the battery pack shrinks, as I want to keep the device in as small of a one-piece unit I can manage. 

Step 6: Monitor

I used the Vuzix Wrap 920 video glasses as a monitor.  They have a 640x480 resolution on each screen, which is pretty good considering the price.  It's a big price to pay if it were a full size monitor, but for video glasses, this is the best resolution I could find for the price.  Vuzix makes a better pair, the Wrap 1200, which sports twin 852x480px displays, but they cost a lot more ($500 on Amazon, more from Vuzix). 

As far as setup goes, connect the glasses to the control box they come with, and plug the RCA adapter the glasses come with into the control box as well.  Then connect the "Video" plug on the RCA adapter to the RCA coupler, and plug the other end of the RCA coupler into the Pi.  Don't use an RCA cable for this connection.  It works, but the coupler is much, much shorter.  I also found that this coupler is extremely snug-fitting.  I did loosen it up a little bit, but it is still a tight fit, unlikely to come loose while carrying the computer around. 

Some people have been asking about what the display actually looks like.  I was actually curious myself before buying these glasses.  When I tried to photograph them,  I realized quickly just how difficult it is to take a picture of such a tiny screen, behind a lens.  I posted the best picture I could get.  Viewed on my computer screen I could make out words in the image.  I don't think it's as easy when viewing the picture from Instructables.  You could try downloading it if it's difficult.  I assure you it's easier to read when wearing the glasses. 

Step 7: Wearing the Computer

This is fairly straightforward, but varies depending on the pants that you wear.  I got a cell phone case that clips onto my belt, so the first thing I do is put it on my belt.  Then, I put the battery pack in my pocket, and connect the microUSB cable to the Pi.  The extra bits of the microUSB cable can be shoved into your pocket.  I put the video glasses control box in a separate pocket since I have two (I'm wearing cargo pants). 

The glasses you can wear when you use the computer.  When not in use, I hang the glasses on the collar of my shirt.  You could also get another belt case for them, or put them in a pocket.  Or just not wear this computer when it's not in use. 

Step 8: Conclusion

I have begun testing this device, and the results seem promising.  First, a few things I will note:
-People around you do not know what you are wearing.  If you are in a school setting like me, this may lead to a lot of questions and such, but overall, I have found that most people tend to react positively once they realize that you're wearing a computer, not a failed fashion statement. 
-You cannot easily see directly in front of you, but you can see around you.  My next version will have a camera system for AR/VR. 

Now for a review of the mobile computer system after some testing:
-I am able to browse the web, type documents, and <nerd moment> remotely connect to my web server </nerd moment> on the go with this setup.  It's a polished system.  I have also tried taking notes on it, which works fairly well so long as people around you know what you are doing. 
-The video glasses I have support a duplex mode where they display the left side of the screen on the left screen, and the right side of the screen on the right side.  Since your eyes are used to seeing the same thing, this is not easy to look at.  Some of my friends that I showed my wearable computer to noted that they could see both sides of the screen next to each other.  However, since I already got used to viewing the two screens as one, I cannot do the same.  I have yet to try extensively. 

A few drawbacks I will note:
-The RaspberryPi is slow.  It's not extremely slow on Raspbian, but it cannot handle much.  I am able to check my emails (through gmail) if I'm desperate, but it cannot handle something that power hungry.  I also cannot play videos through VLC at all.  If you have better success, please let me know! 
-Typing on this keyboard is still different than a desktop keyboard.  It's not quite a phone keyboard, or a tablet either.  It feels like a desktop keyboard when I type, but I cannot attain the same speed. 
-(SOLVED) I do not have a power switch.  When I find a suitable case for my battery pack, I will add a switch.  Until then, I've been unplugging the Pi when I turn it off.  This is a minor inconvenience. 

And, while I'm at it.... the next version will have:
-A significantly slimmer profile
-Extended battery life
-Lighter and easier to carry around
-Anything else you can suggest.  I'm open to new ideas. 

Well, there you have it.  Let me know what you think.  Is this the way of the future?  Or is this too much human/computer integration?  Either way, I think it's pretty cool. 

Comments

[jped]

Hey, this looks amazing.
I am planning on making one of these over the summer. However, I had in mind to make something that is a peripheral to my phone (like google glasses). I want something where i can recive text (possibly return) and also emails. Do you have any advice

[pyrohaz]

Thats absolutely awesome! I'm thinking of making the same thing though I want to have the image projected only into one eye. Have you tried just using one side of the glasses to see if its possible to change focus between the foreground and background?

Either way, cool project!

[Nick_de]

Nice project! Have you tried overclocking your Raspberry pi? You should be able to safely go up to 950 MHz. If are worried about overheating check out my shop: I offer a tiny fan and set of heat sinks for the raspberry pi www.etsy.com/shop/bitcrafts

[meztek]

I'm up at 1GHz stable, actually. Haven't pushed any higher, but it seems my Pi could handle it. Only problem is it doesn't run all that much faster. I've noticed my Pi still sits at 700MHz a lot, even when I think it could benefit from going faster. I'm sure I could change that.... but I haven't bothered to I guess.

You've got some neat things up on Etsy. If I didn't already have piles of SD cards, I'd be tempted use a microSD card for the Pi....

[snotty]

There's a new generation of video goggles coming out.

http://www.kickstarter.com/projects/1523379957/oculus-rift-step-into-the-game

[meztek]

I've seen those. That's definitely another option, but the resolution isn't terribly much higher for the price, and they're kinda big. For virtual reality, it's great. But for a portable setup? I suppose with the way it covers your eyes it would be good for AR.... but I'm frightened to think of what would happen to the poor RaspberryPi if we tried to have it stream a live video feed to the monitor all the time.

[jairuncaloth]

I think going li-poly here would be a reasonable option. Lighter, smaller, and quite a bit more power. The tricky part is dealing with charging and such but even then, there are several pre-made packs that would fit the bill if you don't want to get into rolling your own.

[meztek]

Yeah, that's a really, really good idea. I've recently improved the battery pack a little bit, but I do think you're right on going to li-poly batteries. The biggest interest I would have is not only more power and a smaller pack like you mentioned, but also cost. The battery pack I used in the project cost a total of $70. When you think about that being for only four AA batteries with a charge controller.... that's a decent 15-20% of the project cost. Any ideas where I could find a pre-made compact pack?

How about li-ion batteries? I should think they would be easier to charge. And since they're used in cellular phones, slim li-ion batteries in the size of a Raspberrypi might be easy to come by.

[instructamaker]

This is awesome you might want to make a wearable desk for the keyboard only so that it is more like typing on a real desk.

[meztek]

A wearable desk wouldn't exactly be what I'd call portable though :/

[nerd7473]

this is epic

[MartijnD]

Nice project! With 2 separate screens you can add 3D vision, download divx files with SBS(side by side) encryption, run XBMC and watch 3D movies wherever you want!
Some ideas:
wifi security camera: supports IR so you night vision
Use cell-phone with video out, instant 3G support, bluetooth, wifi,...

[maurop]

http://www.instructables.com/files/deriv/FYT/DK3Q/HAQ37PJX/FYTDK3QHAQ37PJX.THUMB.jpg

[philip42]

How readable is text on the video glasses? The main limitation in your setup is using composite video out. That limits you to standard TV resolution, roughly a maximum of 40-60 characters across before you get bleeding, especially with a color display.

[surpcrepair]

I wont knock your idea because I like rasberry PI although I still haven't grabbed one for a few reason main becuase you can get a small android computer that is dual 1.5ghz 1gb ram has hdmi output and microsd card slot and 1 usb for like $50 so it has much more support then the PI and much better specs and not much more price..

But I wanted to say that I have a samsung galaxy s3 I paid $200 for it from att.. It has android, gps, lte 4g net, wifi, phone, 8gb internal mem, 8gb microsd, dual core cpu, huge amount of ram, latest android, and can easily be hooked to a pair of those video glasses.. So the point I am making is my phone is 20x better then the PI and will hook directly up to some glasses/headphone and have pretty much a fully running computer that is as powerful as some decent netbooks and easily fits in one of those little pouches and has WAY more features then the PI as well as much more support for thousands of apps to do different things, most of them being free as well as if I wanted to I could make an app for it myself..

So wearable computers are already very much available and very easy to get, you can get a pretty decent spec smartphone for like $50 now days so I mean while I get what they are trying to do with the PI I don't see it replacing the android market anytime soon, maybe if it was $5 instead of $50 once you pay shipping, and the specs went WAY up since it isn't even in the same ballpark as the cheapest android platform systems.

Good job though! I would do a project like this just for the experience of doing the project not really caring much about the info i posted above so I would still do it myself, my main things about not wanting to do it is those eye goggles don't work well with people who wear glasses as well as they have not come far enough with their technology to really be feasable for normal use unless maybe you get one of those $1000 pairs that are kind of bulky.. The ones I see have to many cables, to big battery that doesn't last long enough to watch one movie, low resolution, ect. I have hdmi on my phone so if they had one that just had a micro hdmi port to hook into my phone for video/audio and not 500 different cables for different devices and a 4hr battery that wasn't the size of a laptop then I would buy one lol

[Bridges-PdP]

Isn't $50 for a decent smartphone only possible if you buy your phone with a new activation and a data plan? There are a lot of places in the world where phone hardware prices are not subsidized by 2 year service plans. What does an S3 cost if you buy it new, factory unlocked. I'm guessing in the $500 range. Also, the R-Pi will let you add all kinds of storage and sensors rather easily. I don't really know if you can add an external drive or sensors to an S3. That would be cool if someone made a snazzy breakout board for the S3 that allowed interfacing all kinds of things with it.

Also, if you 'get what they are trying to do with the PI', then everything you said in the paragraph after those words has no bearing. Please don't take all of my words has hate or frustration. I guess my point is that this instructable shows one way to do it at a certain price point. Your way would be at another price point.

[aeszok]

I lost you when you said you could hook up an S3 to the video glasses... I wasn't aware that it had RCA out, or even mini-HDMI ;)

[surpcrepair]

There is a small $25 cable that you plug into the usb and it gives you a usb for charging and an hdmi.. RCA no but why in the world would you want crap RCA lol HDMI ftw..

All in all I could get one of these cable adapters so I have hdmi for $25, get an extended life battery (becasue my battery doesn't really last more then a couple hours if you actually use the phone) and a self powered set of glasses that accept hdmi and lose about half the weight of this system as well as cost the same if you had to buy the phone, half if you already have the phone and do 100x times more stuff with it, have much more speed and much more memory.

If you really wanted to go hard you could take an s3 or another smartphone and remove the screen which takes most of the power and hook it up to the glasses and use it strictly for computer and have the wifi so you don't have to pay a cell bill and use google voice you can still make and receive free txts and emails with gmail..

[Istarian]

That's pretty expensive for a cable that just breaks out existing connections.

RCA is much easier to handle (you can generate it in software with a decent microcontroller) and it has a nice round stress resistant connector. It's also to some extent ubiquitous, even now that it's not put in everything by default.

HDMI requires some serious processing power and a very high-res screen (you need at at least 720p to benefit). I doubt you could tell the difference between the two at 640x480.

You could lose the weight, but you'd lose the versatility and be dependent on an app store app or a ton of extra work to free your phone from being locked tight, maybe drop android and run a different linux. Besides your phone offers zip in terms of ways to hack sensors and other I/O peripherals into without the hassle of USB. I'm pretty sure the S3 has nothing for GPIO (General Purpose Input/Output).

Simply put, it would be much easier to use the raspberry, and especially so at the prototype stage.

[ajory72]

Please dont take this the wrong way, I understand what you are saying.
But, Meztek has provided alot of detail on what to buy, and where to buy, the wearabel computer. Not to mention supporting open source software/hardware in the mean time. All you have provided is your thoughts.... why dont you buy the gear you are talkign about and set up a wearable comptuer and share how you did that? in other words.... put your money where your mouth is.

[surpcrepair]

oh yah and they make those types of keyboard mouse controllers that run on bluetooth that will hook to any android phone so you can have the keyboard and mouse also.

[rapidprototyping]

im so excited i posted twice

[rapidprototyping]

I got the new linux bible with all the linux versions on bootable cd and DVD for like ten dollars I never heard rasberriy pi before i bought coby tablet pc for 89 dollars its a android running ice cream sandwitch. i love the touch pad mainly i use it for book reader for books off projectgutenberg this pi device reminds me of xybernaut computer. one advantage you have now is your there its working and you can add storage. micro card slot to run different apps its all about apps with smart phones maybe pi about one app you will probably have to write it good luck

[Sgt. Cookie]

Are there anything else that could be used as a monitor, instead of video glasses? I ask only because they are a little expensive.

[he who crashes often]

try taking a small lcd screen (2 inches or so) which can be bought for under $30 on amazon, and attach it under the lip of a baseball cap, covering one eye. you can then either cover the other eye with an eyepatch, or if you are good at focusing one eye at a time, you can just focus on the screen when you want to use the computer, and focus on other stuff when you are just walking around. however, the screen uses rca connectors, so you will need a converter of some sort to connect to the rasberrypi

[he who crashes often]

for a time, there was a set of video glasses on hobbyking.com called the turnigy "basic" video glasses, but they were removed after a couple weeks because it was found that half of them did not work coming from the factory. it's a shame, because they only cost $75

[etrombly]

I think the board is a little larger, but since the majority of the price is in the glasses already if you want better performance you could try one of the slightly higher specced boards. The odroid-x might work well http://www.hardkernel.com/renewal_2011/products/prdt_info.php?g_code=G133999328931 . To wear the glasses like that I would definitely want some type of video passthrough with a webcam and some type of hud. I don't think the raspi would be able to handle that.

[aeszok]

This is FANTASTIC. I've been wanting to do this sort of thing for a while, but had no idea video glasses even existed. A few little things that might be obvious, but would like to point out anyway; The mintyboost charger circuitry only puts out 500mah of power as far as I know, and the people at RasPi recommend a bare minimum of 700 or 800, which usually means about an amp in real life usage. The 500mah means that you might find it challenging to put enough power out of the already underpowered USB ports to add anything more than the receiver on. But I haven't done this, so these are just assumptions. Overall, a great instructable, be sure to keep us posted on the revisions you make to it!

[schumi23]

Otherwise, he could put 2 Mintyboosts in parallel... I think that would make a max output of 1Amp, no?

Awesome project! If I had 400$ to burn (Unlikely, being 15 years old, frivolous money tends to be quite tight) I would do it.
It sounds awesome. I would love to try it on...

[aeszok]

That sounds about right, and I'm in exactly the same situation, I turn 16 in a few months and I still can't find a job for the Christmas break, otherwise I'd be doing this sort of stuff every weekend...

[4lifenerdfighter]

What kind of image quality do you get from this? Can you read this comment on it?

[amandaghassaei]

I love it! I've been wanting to get a pair of glasses like that and try out some virtual reality type stuff, maybe with an onboard accelerometer/gyro to track movement, too bad the pi doesn't handle video too well, I'm sure we'll have something tiny, cheap, and hackable that can soon...

[farna]

Just use a bigger belt case for the RPi and the batteries. A small camera case would the trick and not be too bulky. A larger camera case with an outside pocket would even have storage for the glasses, but might look too much like a purse for most guys...

[Derpancakes]

This is great! I've always thought wearable computers would be amazing, and for around $400, this seems fairly reasonable. I've been interested in venturing into the Raspberry Pi, and I think this is where I should start.