Its Khawaji again, and I just returned from a trip to rural Sudan with an XO laptop and I'd like to share my experience.
Baby Steps
The XO as an educational tool has so much potential, and puts such a vast horizon before children that one can't help but be excited, but the difficulty in realizing that potential lies in the first step.
How do children who have never seen anything remotely like a computer (in the case of these children probably not even a cell phone) react to this sort of thing? I was able to test that out briefly as I was in a very rural area last week, and was delighted to see that they took to it immediately.
There was a bit of impatience with the slow boot time, but within 15 minutes I could get them to record songs and videos of themselves. In this video, Abd ar-Raziq explains the process of how his family grows tobacco:
I also got them started typing a little bit with the word program (somewhat difficult since I don't have an Arabic XO - though it looks like the pootle translations for Arabic are done... anyone know how to install it?). After about a half an hour though, I was really scratching my head for something that they could pick up quickly and see the results of.There really is not a lot of software on this machine that makes sense to a kid who has no prior exposure to electronics. Even the very concept of a drawing or icon on a screen being representative of an object in real life is pretty abstract and arbitrary (like the cars in etoys, for example).
Imagine if you didn't grow up surrounded by street signs and stick figures - it would not be intuitive that : ) represents (smiley face) which represents a human being expressing happiness. Or to pick an actual example from the sugar interface, that a 5-pointed decagon with three lines flowing from it represents a shooting star, which represents e-toys (the ultimate significance of which I have failed to grasp - does anyone else out there feel like e-toys is very strange?)
Maybe the demographic I am talking about here simply requires a different version of Sugar that is even more basic and user friendly (actually maybe that isn't a bad idea generally, that a student would graduate towards successively more advanced interfaces or OS').
What is this XO thingy?
OLPC without limits
The other major aspect that is important for kids to be able to really get into this is the ability to keep using it - if they are concerned about using up all the battery and not being able to charge it, they will never get past the first few steps because they will use it sparingly.
The XO will work as an educational tool best when it is not only ubiquitous, but always usable and deeply integrated into the child's daily life. Most of us who relied on computers only after we had completed most of our education probably thought of them as tools for specific purposes like word-processing, or formulating tables, or whatever, and only after quite a bit of technological development and re-learning began to realize their nearly limitless capabilities in many aspects of life.
If these kids start without that pre-conception of "computers are for doing such-and-such," and they have a tool that they can take everywhere, then they will probably open up new ways of using computers that we haven't even considered. And, more importantly they will learn at an alarming rate as they discover the world through the XO.
So how can they keep their XO powered up? Well, I am hoping that the human-powered machines are out there somewhere, but I don't have access to them, so I have done some brainstorming on my own. Electricity in developing countries is notoriously irregular, and often non-existent in more rural areas.
"I've got the power!"
But there is one widely available source of power at a constant voltage the entire world over. Can anyone guess? Car batteries!
I lived in a squatter settlement in western Africa for 2 years and all of my neighbors powered their televisions, lights, cell phone chargers, etc. with car batteries which they would take every week or two to the guy down the block who had real electricity and he recharged them for a small fee (I decided not to take the risk of burning down my shack).
It just so happened that I was setting up a Solar panel system on my recent rural trip, and the panels were set up to charge car batteries, so I had a chance to try it out myself. Unlike the Kenyan who commented on my last post, I did not have an inverter, though, and I had to be innovative.
I was not about to fry my XO, and I know very little about electricity, but the adapter on my green machine says that it converts to 12V, which is what a car battery produces. So I cut open the wire and spliced it to the cables coming directly from the car battery.
Yes, we have the XO power!
For anyone adventurous enough to try this at home, when you cut the green wire, it has an inner wire sealed in white [which is the negative, if I remember correctly] and this is surrounded by the positive wires twisted around.
This arrangement is the first non-hack-friendly aspect of the power supply, because it can be fairly difficult to separate them and strip the extremely fine silver wires without breaking or cutting them.
Everything seemed to be fine, so I slowly plugged in my unregulated wire configuration with great trepidation...and the light came on, followed by an extremely high-pitched noise (probably only audible to dogs and small children) that made me wonder if I should duck for cover, lest the battery explode.
Instead I unplugged it hoping I hadn't ruined anything, and after checking for any burning smell, I decided to try resplicing it going through a fuse which was connected to a light fixture in the solar panel system, since this also was supposed to be running at 12V. I again plugged it in and at first it actually seemed to work, but then the sound came back, I jiggled it around and it went away; then a minute or so later came back.
I thought I had enough juice to start the machine by this point, so I decided to just let it go, but it only got part way through the boot-up sequence before dying. I was getting concerned that the sound might have been caused by something moving at an extremely fast speed (though they claim it has "almost no moving parts") and I got worried it would lead to permanent damage, so I decided to try something else - rig up a car charger, like the kind you stick into the cigarette lighter.
I had brought one to charge my Thuraya satphone, for security purposes, and it gave a 10V output, which I thought would be too weak, but I figured at least it wouldn't break anything probably, so I respliced everything again, and tried this, and miraculously, it seemed to work, and was not making an apocalyptic screech.
I tried booting it up again, but again it crashed part way through the boot up sequence... after a couple tries I realized it was probably just because it was charging at too slow of a rate, so I made sure everything was completely off and left it to charge overnight, and in the morning I was at 100%! It booted up fine, and though it was losing power any time I actually used it, it would still charge when I closed it.
Powering OLPC in Sudan
Lessons Learned
So the moral of the story is:
- we really need to make the electric input on this thing more hackable, or at least more flexible
- not all 12V were created equal - it was very smart of OLPC to not just choose a random voltage like 17.6, like most laptop manufacturers do, since car batteries are so ubiquitously available as a relatively stable voltage source.
But they aren't actually 12 V, they run a little bit above that - usually between 13.2 and 12.6V depending on the level of charge. The laptop should be able to run off of this level of power without throwing people into epileptic fits and attracting every dog in town.
- when do we get to try out the actual human-powered XO's?
- can they do G1G1 for an expanded power pack (as a way to finance the new batteries that will be needed in extreme temperatures, as they are finding in Mongolia)?
Khawaji is a NGO worker in Darfur and wrote about One Laptop Per Sudanese Child in January.
the XO power supply puts out 12v, but the laptop is designed to run on a much wider range. from the wiki: "11 to 18 V input usable, –32 to 40V input tolerated". note the negative -- this means you can plug it in backwards to your car battery and nothing bad will happen.
see http://wiki.laptop.org/go/Hardware_specification#External_connectors
as to your high-pitched whine -- i don't know what to make of that. you're sure it was a 12V car battery, and that it was properly charged?
I'm not an electrical engineer (mechanical rather, but just a student), but I know the high-pitched whining it from tiny vibrations from the transformer or inductor coils (even when they're sealed in epoxy). The actual cause is probably fairly complex; resonance frequencies and so on. The XO will contain a DC-DC power supply built in to convert any of those input amounts to its desired voltage, whatever than may be (5-12 I'd assume).
I would have expected the design to expect dirty power sources, or to handle low-current sources nicely. My Dell laptop's power supply will whine when it's in stanby, changing frequency with the pulsing LED (I'd assume it draws very little current and the power supply "doesn't like it").
I have a friend that took an old bicycle, removed the rear wheel and welded a support frame plus a car alternator in place of the wheel. A chain sprocket was welded to the alternator shaft and driven by the bicycle pedals.
With a quick bit of wiring and a car voltage regulator it was charging batteries.
If a source of running water is available a water wheel can take over the effort.
In many semi arid places water is scarce and wind may be more viable.
We already have the cow powered generator but there are hundreds of possible alternatives. Solar energy is just the hi-tech option.
The center connector is positive on the XO's power cord, and the laptop. If the cable's wired like I'd expect it to be, that'd mean the white wire's positive and the shielding is negative.
One can source connectors in all sorts of places, some of which are easier to splice, like the radio shack cables.
This post reminds us of the posts on the XO mailing lists about the Indian effort to use the Fiat alternators and a bike sprocket. I see to recall there the issue was the non-standard diameter of the XO power input. Did anyone actually ever source a connector for it on the open market?
Ned