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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?"
does GPS equipment from the US work over there?
Ok, a quick explanation of how this stuff works is in order. GPS stands for Global Positioning System. The system consists of 24 or so satellites that provide nearly complete coverage of the globe at any given time. By capturing signals from more than one of these satellites, your receiver can calculate your position based on the last known position of the sats. Thanks to the precision and accuracy of modern electronic hardware, this calculation can be accurate to within 20 meters or less.
More info here
So to answer your question, of course GPS equipment can't be used over there! They use 220V AC and we use 110V AC. Where do you think you're going to find a charger? You need to get yourself a step down transformer, or you'll never be able to charge the equipment! Yeash, what are they teaching you kids these days?
Javascript + Nintendo DSi = DSiCade
And instead of rugged, think small. You can get a small GPS that you can plug into your laptop via USB for under $100US. Should outlast the laptop.
As for mapping software, if you truly want it to be useful, just save off the coordinates and wait until you get Internet access, then integrate with Google Maps using their recently released API and you'll be able to actually look at the villages from above, on your computer.
Actually, this is the perfect time to be doing what you're doing.
does GPS equipment from the US work over there?
No. We made sure to send Africa very very degraded signals. How much does a meter of accuracy matter in a desert or jungle anyway?
pooptruck
Google Map, Google Earth or Google Satellite?
Wait, and it'll be built.
Rock that crushes, Paper & Scissors that don't matter.
Even fairly basic GPS receivers come with built in compasses. Never hurts to have a back up though.
Don't blame me, I voted for Durga.
I travel in the US with a GPS in my laptop bag (Garmin GPS V), but depending on where you travel in the world, you may want to insure it doesn't violate any local laws. For example in (don't mod me funny) Ex-Soviet Russia it is illegal in most cases to have GPS equipment. You can be thrown in jail and it may not be pleasant.
unless you get the discounted Global -except West Africa- Possitioning System.
http://www.watacrackaz.com
To my knowledge, Trimble makes the best/most rugged GPS units available. They supply the military. They also have specialized equiptment for mapping. Here is the linkage: http://www.trimble.com/
There are also armored/waterproof cases and what not you can get for the more common off-the-shelf units.
As for software and compatability...I'll defer to someone else to post on that.
(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
To use a GPS device in the southern hemisphere, (ie south of the equator) you have to hold it upside down.
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.
APRS could be your new best friend.
mstyne: real name, no gimmicks
http://gpsinformation.net/
Hope this helps
He who knows best knows how little he knows. - Thomas Jefferson
If you're looking for something compact, rugged and with a decent screen, the Garmin 60CS would be a good choice. I've had mine for two years and have put it through hell - backcountry hiking, sailing, flying, dousing it in mud, beer and water (it's waterproof.) The screen is small but readable in just about any lighting condition (great in direct sun!)
My only complaint with Garmin is the expense of the maps, but I've yet to see much serious competition as far as hardware goes.
I think that a handheld (Palm) would be more convenient for measurements than a laptop. Handheld and GPS receiver do fit in your pocket and they have less moving parts than a laptop.
extern warranty;
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{
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Good generic GPS info plus specific tips for mapping in Africa to be found here: http://www.gpswaypoints.co.za/
Don't invent the field of cartography from scratch. Study it before you leave.
I don't know what "mapping" means in your case. Are you trying to show where each village is or are you trying to create street maps of the major towns? In any case, find out what maps already exist, then go get yourself the best satellite photos you can find, and when you get there, prepare to rent small aircraft for some aerial photography. Trying to map West Africa on foot from scratch with a pocket GPS device would be a fool's errand.
And be VERY CAREFUL. People who make maps are often considered spies by people who carry guns. You'd better be very sure you know what you are doing and have the necessary permission from whoever (official or unofficial) controls the guns in the region you are mapping.
"Those who have never entered upon scientific pursuits know not a tithe of the poetry by which they are surrounded."
You should also be careful of the impression you make on local police or military personel. I don't doubt that many of them would be suspicious of an American (since you asked about U.S. equipment) wandering around with electronic devices to map villages or roads.
Never mind that if the military or intelligence agencies really wanted to know where things were, satellite images would be even more accurate than a cheap/rugged GPS. Many West African countries make it illegal to photograph airports, military bases, police stations and the like.
I'm not saying don't do it, just be careful who sees you. No reason to give excuses for an anti-western, self-important jerk with an automatic rifle to harrass you.
There might be villages that don't want to have their exact location well known.
Lots of these villages have been at war with other villages and tribes for a long, long time.
Many African governments are currupt, and would love to do ethnic cleansing.
Your wanting to provide accurate maps might do more harm than good.
I can just see some Diamond company in the USA, which hears about a new mine that had Diamonds at some coordinate. They then look at your map, and exterminate a whole village. It has happened in the past
This should be a map that only includes those who wish to be included. Don't force anyone on the map. Some tribe might decide to have you for dinner.
Rosco: "If brains were gunpowder, Enos couldn't blow his nose."
latitude, longitude, elevation, time
*Everything* else is interpolated from that info, and if you lose satellites, you lose everything. Even if you stand still, GPS won't tell you where north is; you have to be moving so it can triangulate.
A GPS has some capabilities that overlap with a magnetic compass, and vice versa, but it is extremely risky and potentially hazardous to substitute one for the other.
That being said, I don't know what the OP was planning to do with a compass for mapping villages anyway: a compass doesn't tell you where you are, it only tells you what direction you're facing.
KeS
Bad Panda! No Bamboo for you! In matters of importance ACs will not be responded to. Want to say something critical,OK
I'm sure many others will cover equipment, power charging and such - I'll cover how you should do this. Well, since I taught in a developing country for a few years, this is my suggestion of how...
Developing countries generally have a huge surplus of labor - it's one of their biggest resources. They also, like a lot of the world, tend to have lots of kids who are eager to learn new stuff.
What you need to do is take several GPS receivers with you and hook up with a local teacher who can integrate GPS ideas and geography in with their lessons. The teacher could even make it a special project working with trustable students to map their own village(s).
The key here is to push as much onto the students as possible so they do the work and they learn. You'll help the teacher, help the students and help make more than just maps.
Do your homework. GSM stands for:
Groupe Speciale Mobile
Maybe my French is rustier than I thought, but I believe that traslates (roughly) as Special Mobile Group.
"I'd rather be a lightning rod than a seismometer." -Ken Kesey
Honestly, you'll be lucky if you get the thing past customs without it being 'confiscated.' They take what they want. This happened to my friend who went to Kenya to help set up a network for his missionary friends. They just up and took a router and other bits of hardware that looked interesting to them and told him to move along. Luckily, he only had one CD of software that he kept in his pocket. He knew this was a possibility, but didn't think it really happens. It happens.
If you're going to bring a GPS device over there, get a compact one that will fit in your pocket.
"There are no such things as mutual fantasies. Yours bore us and ours offend you."
- Bill Maher
I've had a very good experience with MacGPS Pro from James Associates. It's reasonably priced ($40) and you can even find free maps and such. I used it in combination with a Garmin eTrex on a recent trip to the Okavango Delta (Botswana) and it worked just fine. No, I do not work for either company.
I travel in and out of Africa about once a month on business, hitting about 15 countries on average each year. I can tell you from experience that it is VERY dangerous to be seen using a GPS near Military installations, railroads, shipping, and anything the locals consider of strategic value. This generally means about everything. You should be extremely circumspect when using the GPS. You may have it confiscated, or you may end up in a cell somewhere with arabic graffiti on the walls. Not good. Your best bet is to make sure you contact your local embassy in the country, and ask their communications personnel about local sensitivities to GPS. You could always ask the Regional Security Officer (RSO) also, but be forewarned that they often err on the side of safety, have a poor understanding of much tech, and could very well say not without a moment's hesitatin to avoid having to retrieve you from your cell when you are snagged. Best bet; use it for quick position fixes, then put it away. It is also not safe to display an item that costs more than most locals make in a month of hard labor. Good luck!
73 SK
HOWEVER, many handheld GPS units, especially slightly higher end ones DO come with built in compasses, and can tell you which way is north even when you're in the basement of a building with absolutely no satellite reception and you're not moving. (My Brunton MNS falls under this category)
Bottom line, you should know what you're buying and what features it has before you get it.
On a somewhat related note, having a built-in compass can be extremely useful, as it will tell you how far away and in what direction a mark is even when you're not moving - it will tell you relative to the orientation of the GPS. Many units without a built in compass only tell you in what direction a mark is relative to direction of travel - so this can be very confusing if you're standing still or haven't oriented the unit in the direction of travel. Hope this made at least an inkling of sense.
Most of these posts are not going to help the submitter much at all, mostly because nobody here seems to know a damn thing about GIS. First things first, what sort of mapping are you trying to do, what information do you want to gather? Hydrology? Land use? Topology? Classification? Next most of the consumer grade stuff is crap if you want any kind of accuracy, if you want really good data, you'll need to get a base station set up and look into dgps, that means you need a better sort of GPS unit such as something from Trimble. Next, GPS compasses, be they electronic, interpolated, or what not are crap. BRING a GOOD compass. You'll probably also want a separate barometric altimeter, and a clinometer, if you don't know how to use and calibrate this equipment, then I must agree with the earlier post that amateur cartography might not be for you. As for software, again really depends on what you are trying to do? orthorectify photos? network analysis? etc...
In short, good luck.
BTW, I have SOME qualifications, a GIS minor, and my Msc thesis(in progress) is about robotic terrain mapping.
"Have fun, don't leave electronics (or anything plastic) on your dashboard - it will melt, and good luck with spelling the village names! It sounds like a fun project."
No, it won't melt. It will get stolen looooong before it can melt.
General rule of thumb: Anything that won't fit in your backpack, will get stolen and if you let your backpack out of sight for 0.000001 seconds, then it will get stolen together with everything in it.
Note that for protection, it is a good idea to carry a hunting knife, but since some places object to knives, consider carrying a small axe instead - there are no laws against axes and it will ensure that you'll be a very popular guy whenever you set up camp and need a fire...
Oh well, what the hell...
While GPS works everywhere, the Wide Area Augmentation System (WAAS) is only useful for the Continental US. WAAS units will work elsewere but they will only have the resolution of standard GPS. If you need better than standard C/A code accuracy use Carrier Differential (CDGPS) mapping using two Garmin recievers and a copy of GRINGO (http://www.nottingham.ac.uk/iessg/gringo/).
The Garmin Rhino units w/ integrated FRS Walkie Talkie units are vaery rugged and may be handy for survey. Additionally, to quote the Operation Iraqi Freedom
PEO Soldier Lessons Learned report:
Commercial GPS: As is widely known, many soldiers purchase their own GPS systems rather than use the PLGR. The Rhino was provided to the 82d as part of the rapid fielding initiative. Overall, soldiers were very appreciative of this addition to their MTOE. The Rhino was a vast improvement over the PLGR because of the weight, volume, power consumption and performance - the Rhino consistently acquired satellites faster than the PLGR. However, the soldiers stated they did not use the communications capabilities of the Rhino, at least not extensively, because it was not secure and consumed batteries too quickly in this mode.
If it survives the front lines in Iraq, West Africa should be a cake walk.
A compass, if you know how to actually use one with a map, can tell you a great deal about not only what direction you're headed, but where you are and, more importantly, it can do something that GPS Just Plain Cannot Do, namely, it can tell you where that unknown landmark is, which in Western Africa is an incredibly useful skill. The last thing in the world a foreigner should do is wander into an uncharted village. Best to get an intersection on it from range, record the position, and move on. Now, this doesn't mean that you shouldn't use GPS. In fact, GPS can be used in conjunction with the intersection technique in order to give you your 'known points'. But don't rely on a single piece of equipment to find your way around some petty warlord's backyard.
Some suggestions for keeping your gear charged up... Portable solar panels: http://www.moderntradingpost.com/powerdock/ and Voltaic backpack with solar panels: recharge small devices with solar power (not enough juice for laptops) http://www.voltaicsystems.com/
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.
If you end up using maps instead of a software, be aware of the datum http://en.wikipedia.org/wiki/Geodetic_system used in the map. Because the earth is not a perfect shape, different countries use different projections, called map datum. You should set your GPS to the same datum as the map you are using.
I was going to let this alone and perhaps let the geocaching or other GPS gadget freaks answer it, but some of the discussion regarding durability and suspicious behavior by westerners leads me to throw my US$0.02 in.
It depends whether you're going to be walking or driving. I have had very good car-based mapping experiences using an older Mac, namely a G3-500 Pismo. I have found the Pismo and similar Lombard/Wallstreet units to be cheap, very functional, unobtrusive, and very durable -- almost to Panasonic Toughbook standards. Though I use both Mac and PC on a regular basis, ease of use pulls me to the Mac for GPS tools. I use mine with a remote usb-connected-and-powered Deluo GPS unit, which mounts on the dashboard or on the roof of the vehicle using a magnet on the bottom. The Deluo has no display or blinky lights to advertise its presence; it's just a 3cmSq bump with a cable. Get a car charger to keep the Mac powered up, use the nifty Control+Alt+Apple+8 to switch the display to "7337 mode" (inverse greyscale display), and you'll be about as unobtrusive as you can get. Less obtrusive than simply being a western guy in rural west Africa, anyway.
On the other hand, if you're going to be on foot, I heartily recommend ditching the laptop and taking an eTrex Voyager or similar model. It's very durable, gets good reception, fits in your shirt pocket out of sight while still receiving a signal, and runs all day long -- thanks in part to its black and white screen -- on two AA batteries. Make a list on paper of waypoints you expect to see, mark them on the eTrex unit using the little joystick when you get to each spot in sequence, and then put it back in your shirt pocket without making a scene. Take a few sets of rechargable AAs and a solar charger, and leave the computer at home for data dumps at the end of each day.
Better yet, take two or three eTrex units (US$60-90 used), and consider them disposable -- expect to have them all eventually stolen from you or seized by various police or military. You may face less hassle and risk if you appear only mildly irritated that a trinket is being taken, as opposed to hyperventiating over someone taking all your data. Eventually you can take the downloaded data and correlate the traces and waypoints using satellite maps or other starting points.
J
I think not...(*poof*)
For most of 2003 and 2004 I was working in rural Madagascar on a reef conservation project (as Diving Manager, Scientist and general tech guy).
We primarily used handheld GPS units (Garmin, Magellan) for mapping the outlines of the reefs. This was accomplished by attching the GPS in a waterproof bag to a float and towing it behind a diver. It was fairly effective, and provided data good enough for GIS work.
We also mapped the roads (read: dirt tracks) and trails in the local area, but the part that seems most approprate to this discussion was mapping the local fishing villages for socio-economic research.
We mapped out the main roads, the major buildings, and all of the houses that we interviewed people at so that we could build up a full profile of the village for input into our GIS work.
For most work, the most basic GPS units were fine (eg. Garmin Etrex, and 7x series - we also used a couple of Magellan and Silva units). Use rechargable NiMh batteries as although they don't last as long as alkalines, you can use a solar recharger to give you an endless supply. (As an aside, only the Garmins were able to run on the crappy local batteries).
As an idea of where we were - the nearest phone line was over 200 miles away, and the only reliable method of communication was satellite phone (radio messages could sometimes get through via several mission relays, but if the weather was off then no chance).
I used a couple of fairly old (P2 233) Toshiba Satellites as my data machines as they could take a beating and keep working (and were free). (Win 98 on both and a dual boot to RH 9 on one)
Hope this helps...
Dan.
Landsat-7 is available freely and cover the whole world, but it's only 15 m (panchromatic) and 30 m (multispectral)
ASTER L1B is also free but the cover is not complete. It's very good data with 3 bands in VNIR. 15 bands total.
SRTM-DEM, for topography, is also great and free. 3 arc-second of horizontal resolution and about 5 m vertically (relative, not absolute). It really is useful data for topography, and it's free.
Where to find this data? Start on my Remote Sensing Table http://www.matox.com/agisrs/arsist
As for software, yes, GRASS GIS works fine on MacOS X, *but*, the learning curve is very steep. I don't know MacGPS Pro. See the two other comments http://ask.slashdot.org/comments.pl?sid=155849&cid =13067619 and http://ask.slashdot.org/comments.pl?sid=155849&cid =13067710
If I were you, I would try to ask somewhere else than /.. Nothing against the /. crowd, it just doesn't hurt to have a second opinion, especially if it comes from GIS/RS experts. You can try the Applied-GIS-RS mailing list http://www.matox.com/agisrs but there are a lot of other groups of GIS/RS specialists. Good luck!
Animoog.org
Hardware:
3 .pdf
Get a Garmin handheld GPS with a 12v adaptor & download cable, and probably a crate of AA batts.
Stick with consumer stuff. Buying a spare or 3 is cheaper than buying a Trimble survey grade and they all work well enough.
GPS Software:
Download GPStrans &/or GPSbabel.
http://gpstrans.sourceforge.net/
http://www.gpsbabel.org/
You can load the GPS waypoints/track/routes into a mapping format with GRASS GIS's v.in.garmin or gpsbabel+anything.
Mapping software:
Use QGIS. http://qgis.org/
Use GPS plugin.
Data:
Start by downloading SRTM elevation data and VMAP0 digital chart of the world data. Best there will be publicly available for Africa.
Instructions for converting into a usable format here:
http://grass.ibiblio.org/newsletter/GRASSNews_vol
Import and crop with GRASS GIS (r.in.srtm and v.in.ogr modules) and either use with QGIS directly or export into a secondary more popular format for use with other software.
GRASS works well on a Mac. http://grass.ibiblio.org/
GPS interface programs should work on a Mac, GPStrans is command line only so with some hacking and GPSbabel is well maintained so there should be a Mac port by now.
SRTM: http://www2.jpl.nasa.gov/srtm/
VMAP0: http://www.mapability.com/info/vmap0_index.html
~.~
I'm a peripheral visionary.
Since you're talking about charting villages in Ghana, worst case is you'll have a 100 meter uncertainty in their locations, which is probably still much better than you have now. More likely you'd have a 5-10 meter uncertainty, and you'd have a similar uncertainty with nearby landmarks (so if the village is next to the river, they're both uncertain by 10 meters but you can see where the river is.)
Bill Stewart
New Fast-Compression-only CPR http://preview.tinyurl.com/dy575ks
Not undeveloped, you insensitive clod!
WARNING: Smartphones have side effects--most of them undocumented.
Most standalone GPS's these days, except for the very cheap ones, do have PC cables as well as built-in user interfaces, so you can get the best of both worlds, but I don't know if they can run on USB power or if you'll need to mess with lots of rechargeable batteries.
Of course, if GPS is important, you need a spare one anyway, so you might as well bring both. They're fairly cheap here, so you may consider leaving one behind as a gift if it doesn't get broken, stolen, etc. while you're using it.
Bill Stewart
New Fast-Compression-only CPR http://preview.tinyurl.com/dy575ks
For the price of two regular laptops, get a Panasonic Toughbook. It will still be useable after exiting the far end of the digestive tract of the alligator that eats you.
Are you kidding? I'm writing this from a Panasonic CF-29...you could close it, beat the alligator to death with it, open it back up, and continue working. They're pricey, but great computers.
And yes, if one has the money for it, I would heartily recommend one of these for such a trip.
Something I've seen missing from the discussion so far is much focus on understanding maps and navigation.
If you don't know how to read and use a map, it'll be much harder to make one that's even remotely useful. Get familiar with topographical maps, at bare minimum, and preferably other types you think might be appropriate. Study some cartography. Go out on a compass navigation training course - with not a single gadget on you.
I mean that about the training course, too. You'll learn much better that way, and learn things properly. Don't just think reading a book cuts it, you need to go out and get experience where you still have someone to pull you out or ask questions of.
Get the permission of the local authorities. Others have outlined why that's a very good idea.
I'd also suggest going on a few multi-day bushwalks before you leave. On at least one of them, preferably with someone experienced, leave your GPS unit at home. Why: (a) Bushwalking is fun, especially multi-day trips (b) it'll make you more confident in your ability to handle navigation and the work involved, and (c) you'll appreciate the practice.
Now, I've made some big assumptions about the sort of territory and environment you'll be working in. Even if you don't need the skills outlined above, though, they're darn good to have, darn fun to acquire, and it never hurts to be prepared.