Unterbahn

The Children’s Environments Research Group at CUNY developed a curriculum with UNICEF on the topic of participatory environmental exploration by children as a part of the urban planning process.

Josh Levinger and I met up with some activists who were planting trees in Umm Salamuna (view in Google Maps) on a hillside which is scheduled to be annexed by a nearby Israeli settlement, and converted into a graveyard. The planting was organized by Alice Gray of Bustan Qaraaqa, so that if the land is taken over, the trees would have to be uprooted or chopped down before the land can be used.. As I understand it, one of the means by which settlements claim land is by using an Israeli law which opens land to new settlement if it has lain fallow for more than three years — so planting the hillside may defend it from such a claim.

The wind was so strong that our first kite, carefully made that morning from dowels and Tyvek, shattered immediately. Instead, we launched a small soft kite with an iPod nano attached to it. Here’s a stitched image of the video footage we captured:

See all the pictures on Flickr.

The iPod has an SD camera which can capture many hours of video – and it’s so super light that we can fly it on a pocket kite. Many of the frames are blurred and the resolution is pretty poor (we’d thought of using a Flip camera but they’re more expensive and heavier) but when you go through the footage frame by frame you can find lots of good images. We then stitched these together with Calico and got the above image. It helped a lot to put a small ’sail’ on the back of the iPod so it didn’t spin as much.

Everyone was cold but once we started flying the kites we all got really excited. The owner of the land was there with his kids and they helped assemble the rig and fly the kite:

The mapping was a big success – everyone ‘got’ why we were doing it, that documenting the tree planting and how they’re changing the landscape is a form of testimony. We’re still working to rectify the imagery, and I’d like to ask folks if they have any ideas – the stitching software we’re using assumes images were taken from a single viewpoint, but the kite and camera were moving all over the place. As you can see above, the stitching distorts things and we lose a lot of detail – how can we reconstruct a high-res image that assumes multiple perspectives? I’m looking at this tutorial to start with. We’re also thinking about an algorithm to dump the clear, undistorted and unblurred frames from a movie file. Ideas?

Update: We’ll be adding this material to the Grassroots Mapping wiki, where we’re putting together a comprehensive guide on low-cost participatory mapping techniques. Our hope is that we can offer a Grassroots Mapping Kit which people can use to reproduce these techniques to explore and document their own geographies no matter where they are.

Cross-posted with the Center for Future Civic Media blog

I’ve been at the MobileActive/Unicef workshop in Amman, Jordan since yesterday, and got to present some of my work on low cost mapping with kites and balloons. One thing people have been asking about is if people in informail communities would object to being photographed from above. While I completely understand this question, it does strike me as odd – they’re photographed from space all the time by Navteq and TeleAtlas, without being asked permission.

First, though, I wanted to make it clear that I’m not interested in developing tools for people like myself to unilaterally image a community – the whole idea is to make tools *for* a community to map themselves — as a form of expression, as a tool for community planning, and as an exploratory process. My hope is that the community I’m hoping to work with in Lima will want to publish and distribute their maps, but that is of course their decision to make.

At the same time, it’s also clear that there is a practical and psychological difference between flying a kite/balloon with a camera on it while you are actually in a community, and flying a satellite which they cannot see, having never visited the community you’re imaging. But I’m hoping that the former can form the basis of a more participatory way of mapping contested geographies. In any case, this is a great ongoing discussion, and I’m eager to see how it plays out on the ground in Lima.

Maybe they could use some magic. Read NYTimes.com article

MobileActive covered a project called Wikimapa by Rede Jovem, where teenagers use Nokia N95 phones to map unmapped areas of Rio de Janiero.

The project cost $87,310. The evaluation section of the article was interesting:

The most challenging part of the project was developing the mobile application. The organization is still working to develop versions for other operating systems. Having a long-term, sustainable budget is also challenging. The project was unsuccessful in getting grants from Nokia — they bought the phones themselves — and currently doesn’t have any money to sustain the project beyond December. Because the project doesn’t actually make money, they are dependent on grants and its unlikely to be scalable or sustainable. — MobileActive.org

I’m going to contact the organizers and see if they’d like to use some of the techniques we’re prototyping now.

Rede Jovem (via MobileActive.org)

The Geohash algorithm is a useful way to describe locations on the earth using a single string of a-z, 0-9 characters. They can be thought of as rectangular subdivisions of the Earth’s surface. Learn more here: Geohash at Wikipedia. They were invented by Gustavo Niemeyer in 2008.

It’s good to get an idea of how large a rectangle a given geohash describes, but this changes depending on your latitude. At the equator, geohashes are biggest, so you need more characters to describe an area of a given size, or a location of a given precision.

In Cartagen I’m using geohashes to report geodata by text message, so it’s very useful to know how long your geohash code will be to describe, say, the area of a building, a soccer field, or a street corner. I did a quick calculation for the equator, which is the worst-case scenario:

Dimensions of geohashes of length n:

I think this is right but if you find an error please tell me. I put it up on the Cartagen Wiki here: GeoHashes

Nice rendering, but not a new idea.

BBC NEWS | UK | Magazine | People-powered maps.

DIYcity is a fascinating effort apparently related to the Open Planning Project.

Our cities today are relics from a time before the Internet. Services and infrastructure, created and operated by the government, are centrally managed, non-participatory and closed. And while this was once the best (and only) way for cities to operate, today it leads to a system that is inefficient, increasingly expensive to maintain, and slow to change.

What is needed right now is a new type of city: a city that is like the Internet in its openness, participation, distributed nature and rapid, organic evolution – a city that is not centrally operated, but that is created, operated and improved upon by all – a DIY City.

Fantastic.