Colony software trialling in York
Right at the end of last year’s residency at the Pervasive Media Studio in Bristol, Tarim and I uploaded the new code he’d been working on to a critter and went for a quick wander before I packed up and headed back to Birmingham.
With a couple of Colony critters having been selected to form part of the upcoming Right Here Right Now exhibition at The Lowry, I wanted to give this code rewrite another try-out to find out more about how it behaves.
Phase II of my recent Tour of T’North was a few days’ stopover in York, so out came the Arduino and the GPS modules…
For the geographically-challenged:
…or if you like your maps a bit more abstract, here’s the data I collected from my walk:
A recap for those of you who might not have been following this from the start (5 years ago!), I’m processing GPS data to get a measure of the error that gets induced in the positional calculations by the built environment. If you’re standing near some tall buildings, these often block the direct path of the timecoded radio signals from the GPS satellites, meaning they instead reach the GPS receiver by a longer path having bounced off assorted architecture. The extra time taken for the waves to travel this indirect route throws off the calculations based on the timecodes in the signals and the accuracy of the latitude and longitude co-ordinates decreases. There are other things that can happen too, but that’s a simplified version of the main effect. I’m interested in how this process can effectively give a fingerprint of the stuff that makes up a place.
The lines in these images are a visualisation of the data collected overlaid, roughly, on the areas where the data was collected. The longer the lines, the greater the error and, typically, the more bricks and mortar there are in the vicinity.
Here are the same lines as above, this time viewed in Google Earth. (I do this as part of my process of looking at the collected data, so I can relate the behaviour of the lines back to where I was and what might have caused that behaviour.)
Getting to this stage was a bit of a learning curve because the data is now being logged in a different format and I had to figure out a way of extracting the numbers I needed to then feed into the script that produces the file that is read by Google Earth. Got there in the end, though! (Nothing too high-tech, just some spreadsheet-fu with 32,000 lines of data.)
Although the Google Earth views aren’t really one of the outputs of the project, I like them as illustrations of the process and, as mentioned above, they are very useful to me in helping to interpret what happened. Switching on the 3D buildings layer is a bit of fun, too!
Here’s the data from around York Minster:
I walked down from the top right corner of the image, meandering through the narrow streets near The Shambles. If you look carefully you might be able to spot where the lines disappear for a bit, as I go down an alleyway and the GPS receivers loose the signal completely. I then swooped out along the bottom edge of the open space in front of the church [first photo below], walked along the outer edge of the grounds, then came back towards the front by walking along the path that runs along the left-hand side of the building. From here I walked along the foot of the wall along the front of the building [second photo below], by the steps and the rather magnificent doors.
You can see how much the lines have been deflected out from the actual route walked, particularly when I return to the front of the building – the lines are in nearly the same place as when I first walked along the bottom edged of the paved area!
After a quick detour to the post office, it seemed like a suitable nod to the city to walk a section of the old walls.
I was a bit surprised at how much the top bit of the ramparts affected the GPS reception, but that’s the whole point of all this really: looking at the results and going “oh, that’s interesting”! Later on in the development of Colony, I’ll be developing a visualisation of the data collected so that the group coming off the walk has an aide-memoire for recalling their experiences and observations.
By way of contrast to all that stone, Phase II finished off with my favourite tree in all of the (just outside of the) city:
