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Best Setup for Mapping in Undeveloped Countries?
Floodimus asks: "My girlfriend lives and works in West Africa and on my next visit she has asked me to help her do some mapping of uncharted villages. I want to make this study really accurate and useful, so I am thinking about using high tech and low tech resources such as GPS and good old fashioned compasses, but I was wondering what the Slashdot crowd would recommend for GPS hardware (does GPS equipment from the US work over there?), field equipment, mapping software etc. I use both PCs and Macs and would like the software to run on the Mac, but it doesn't have to. What's the best, most rugged stuff you've used? Where are some resources that would help me out?"
There's plenty of GPS-equipment that run on batteries though. If he's going to be trecking through Africa, that is most likely his best bet anyways.
"" How about taking the safety labels off everything, and let the stupidity-problem solve itself? """
(does GPS equipment from the US work over there?), field equipment, mapping software etc. I use both PCs and Macs
1) GPS equipment, bought anywhere in the world, works anywhere else in the world, since GPS satellites cover the entire globe
2) All you describe is fine and dandy, but it seems to me that you're forgetting one crucial part of it: power supply. In the Middle of Nowhere, West Africa, you may not be able to find wall outlets everywhere to connect your laptop to everyday. What's more, if you do find power, your laptop might not like it (voltage spikes, bad frequency...).
So my suggestion is that you start designing around your power supply. Solar? Generator? how to conserve power? PDA or laptop? what size battery to you expect to need? etc etc... all that depends on the exact application.
"A door is what a dog is perpetually on the wrong side of" - Ogden Nash
My first thought isn't what equipment would be the most fun or powerful, but what equipment will work. How reliable will electricity be in the area you are going to be mapping? Since you describe these areas as uncharted, ,y guess would be "not very," so don't expect that Mac to always be available to you.
Now what are you going to do without that laptop? You're going to need a GPS device that runs for a *long* time on batteries, or you're going to need to bring a crate of batteries where you go. You're also going to need something that allows you to save and tag all this GPS data so that you can decipher it when you do get back to a computer.
Get that figured out, and if you have any money left over, THEN you can start thinking about buying that copy of ArcView.
read the wikipedia-article you referenced. Surely, 2 satellites are not enough. 2 will only give you some delta pseudorange. For full coordiantes you need >= 4 sats.
just bitching
The G in GSM also stands for Global, and AFAIK you can't just walk to another country and use your phone if your company doesn't have roaming agreements with the local companies. Also at a lower level, you need a dual (900/1800MHz) or triple (900/1800/1900MHz) band cellular to be fully compatible with all Global System for Mobile Communications networks.
I'm not saying GSM works the same way as GPS, I'm just saying that Global doesn't necessarily mean that the it works or is compatible with the rest of the Universe.
well unless its a mechanical compass glued into the gps, its not going to be much use if the unit fails. obviously the backup/s will come into play. anyone who goes into the bush without survival skills, a map and compass is going to end up in a lot of trouble, and probably as some bleached bones pointing a warning for anyone else trying to play the great white explorer with only modern technology behind them.
Also it should be noted that in certain countries it is illeagle to possess maps over a certain level of detail. Make sure you understand the laws of the country you are going to, and work within them. If you don't then you will not only be considered a spy, you might legally be a spy, even though your intentions are noble or benign.
Fantasy remains a human right; we make in our measure and in our derivative mode... -- JRR Tolkien
Then again, if your GPS receiver is bus-powered (like this one) and if your notebook comes with an auto-voltage power supply (99% of them do), all you'll need for it is an adapter to go from an American plug to whatever you need where you're going (like this, which is supposed to adapt to nearly anything).
(There's a fair chance you'll need transformers for some of the other gadgets you might bring along, but your computer and GPS receiver probably aren't among them.)
20 January 2017: the End of an Error.
And every uncharted village has power outlets he can just plug into.
Trying to map West Africa on foot from scratch with a pocket GPS device would be a fool's errand.
He's going to visit his girlfriend. This is her way of keeping him busy when she's working and/or provide a noble sounding excuse to buy new toys when what he really is going to be doing is eating, drinking, and shagging.The plane charter will be of great assistance in contextualizing what you see on the ground against what your sat maps show. You may also be able to spot commonly used trade routes, animal migration routes and footpaths that don't show up as readily as established roadways. Many maps are not able to provide these more subtle details out of concern for clutter or overdoing the scope, but ethnographers, anthropologists and biologists can appreciate it -- especially in areas they don't get to very often. Getting a bush plane is a great piece of advice.
Stuff I'd add:
Creating a street map of any towns you visit can be one way to meet a lot of people and enlist the help of locals. Be sure to leave a copy or two of the map in-town, and follow up by leaving copies at the nearest government office and university.
I'd also suggest affiliating yourself with a geographic society before you go. It may help garner some contacts when you get there (professors, government officials, etc.), and also a way to get some more locally-specific advice about where to go, what areas are most sparsely covered by cartographers/surveyors, etc. Contact the Interior Ministry. Contact the geography professor at the university. You may be able to get some assistance from students, and it may help you get any necessary papers or authorizations required to make the trip more problem-free.
If it's suggested that you hire guards in an area, get help finding some that are trustworthy, hire them and pay them well. This is one area where having some local gov't or university contacts ahead of time can really help.
It sounds like a blast. Good on ye and have fun!
.. pa-ra-bo-la, pa-ra-bo-la, 2 pi R, 2 pi R, where's your latus rectum, where's your latus rectum, 2 pi R
I recently spent two years in southern africa as an engineer on a skills exchange. For what it is worth you should be able to feel comfortable with your own answers to the following.. Is what I do going to be sustainable? Will I be able to transfer the skills for others to maintain the maps after I return home? If you are bringing your own equipment, will locals have the equipment after you leave? Will locals be able to maintain the equipment / software / data ? As you will most likely apear as a well-off foreigner, how will you deal with security of your equipment?
That being said, variable power and heat are hard on gear. Look up service addresses etc. and leave the info with your reliable friend who will juggle things for you on this end.
And have fun, and be respectful. The impression you create is as important as the maps.
I hope when you said draw, you didn't mean draw with a pen or pencil kinda draw :) Anyway, I recommend he just grabs a gps receiver for laptops, a laptop with a car adapter, and the Pro version of Google Earth. Hook up your GPS receiver and just walk around the village, Google Earth will make the map for him and it has pretty high-def satellite images. If the village is so small that satellite images are not close enough, just use the software that came with the unit or one of the many open source GIS programs to automatically map it for you as you walk. I'd recommend using Google Earth though, as the map will read much better with terrain and semi-recent details of the village roads and trails. You'll also be able to tell if you've missed any big landmarks or anything.
Regards,
Steve
It's true, be discrete. Though, most likely the worst case is probably they take the GPS away, and haul you down to the police station for a while, until you cough up a bit of cash. Being from North America or Europe makes you an instant target for trying to get a quick bribe. If you are out in the middle of nowhere, no one's going to care that you have a GPS, most people won't have a clue what it is. Just be careful about having anything electronic visible around the authorities. Get a small GPS unit, and keep it in your pocket.
I did a bunch of mapping in central Mali about 10 years ago. I was helping a guy map wells in abandoned towns (they were abandoned because of the Twarag war which had ended a few years earlier. He was doing a survey to see which villages had a useful water supply, and which needed work) Anyhow. It's not likely you would get in overly serious trouble for having a GPS. Bring two in case one gets confiscated or broke. A low cost Garmin GPS works just fine (they are rugged enough), I was getting acuracy to + or - 19meters when I was there. It should be much more accurate now.
With a paper map bought at your local book store, a ruler and some simple math, you can put together a quick map. Some of the other mapping software mentioned in other posts works better for custom projections, but can be much more involved and time consuming. Double AA batteries are plentiful in Africa, so powering a GPS is no problem, though when you buy them, try them while you are there and make sure they work. If you are spending serious time on a laptop out in the bush, the best bet is to have an inverter to plug into a car, or a solar panel if you want to be fancy, and have extra money to spend.
The sand in the dryer areas of West Africa can be hard on equipment. I was in a sandstorm once, my video camera was never quite the same after that. The humidity in other parts of West Africa creates it's own problems, but nothing that can't be worked around. I had and still have a Garmin GPS 45, which survived traveling a large part of the globe unscathed, and continues to work 10 years after I bought it.
Keep it as simple as possible, keep freqent backups of data, and don't take anything with you that you aren't willing to part with.
Have fun
The last half of this statement makes no sense. Since the GPS system was developed by the US military to precisely deliver military assets, why the hell would they turn it off in a place where they would use it the most i.e. " in countries the US is at war with"????????? Do you mean TURNING ON Selective Availability? And I don't think they use SA that much now anyway because many of the troops are using commercial versions they bought for themselves. Even with SA on the GPS is still pretty useful (probably not for making precise maps, but definitely good enough to show Point A relative to Point B and the route in between when the distance from A to B is measured in miles or kilometers.)