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Wheelchair Accessibility Mapping Party at UCL

As part of the induction week for the new cohort of the MSc in GIS here at theDepartment of Civil, Environmental and Geomatic Engineering, I organised aOpenStreetMap Mapping Party. OSM mapping is not only a fun activity that gets the students out of the classroom and getting to know each other, but also serves as a convenient introduction to a wide range of geo-challenges relevant to their MSc, both in terms of data collection quality and attributes, editing and updating of spatial data, as well as the visualisation and processing of collected data.

Central London is already mapped to a high level of detail (not astonishing given that OSM originates from UCL!), so we decided to focus on a much neglected topic, ie wheelchair accessibility mapping. Wheelmap.org, a relatively new initiative to highlight wheelchair accessible places, made it painfully obvious that almost no accessibility mapping had been done so far in and around UCL!

Catherine Holloway, a wheelchair accessibility specialist from our department, gave a great overview of relevant attributes to map, and even brought along a couple of wheelchairs for the students to sit in! Two of the student groups experienced the difficulties when trying to move about in a wheelchair, hitting obstacles, bad dropped kerbs and rough surfaces, a valuable insight into the very specific mobility problems of London’s wheelchair users.
The mapping party was also kindly supported by members of the OSM community, ie. Gianfranco,  Derick Rethans, and Alex who shadowed groups and supported them.

The first day was taken up with data collection, and the weather god(s) were very kind to us, with atypically warm and sunny weather for this time of the year, ideal to explore the different areas around UCL’s main campus. We subdivided the area into map slices, and 4 groups went off to collect data, each group recording their progress on walkingpapers print outs. After some initial confusion over what to capture, the groups soon got to grips with the task and went their separate ways to record: if shops and building entrances have step free access and if the toilets are wheelchair accessible; where dropped kerbs are; as well as pavement quality and minimum widths.

My group did south of UCL around Tottenham Court Road, and sadly we found a whole row of shops not wheelchair accessible in Store Street (see photo above). I must say that I was shocked by the number of businesses, pubs and buildings which today are still not wheelchair accessible, just in the very small area we mapped around UCL. After a productive two hours of mapping, we reconvened at the Department, to go for a well deserved pint of beer in theJeremy Bentham pub (an essential part of any proper mapping party!).

On day 2, the students sat down to add their collected data to OSM, using Potlatch2. Andy Allan, one of the lead developers of Potlatch2, joined us for the lab session to support the students, but also importantly to experience how first time editors of OSM are using his software. In parallel, I setup screen recording software to gather new data on first time users interactions with OSM’s editing tools, in this case Potlatch2, in continuation of earlier work done in usability analysis, reported here before. Apart from some of the previously discussed problems in the usability of Potlatch2, of which Andy took keen notice and I am sure he will report back on as well, the students got on well with the editing. Soon the first changesets appeared on OSM, and the first tagged shops were updated as well on wheelmap.org. Some students even managed to finish early, taking the opportunity to edit and add information around their homes.

The results of the mapping party can be seen in the changesets generated by the students, as well as the numerous classified shops and amenities along Tottenham Court Road and its sidestreets, visible in wheelmap.org, where before there was just a sea of grey unclassified Points of Interest.

State of the Map EU – Presentation available online

Just a quick pointer to the recording of the presentation of the joint work between Dr Catherine Jones and myself here at SOTMEU (I only got the video to work in Firefox!) So, far a great and vibrant conference, and our research into usability issues in OpenStreetMap was well received. I was particularly pleased by the positive reaction from a lot of conference attendants to our work, it seems that most core community members are well aware of the issues we raised, and recognise the need for improvement.

This small research project from us then represents the first of an ongoing effort to better embed and implement a usability engineering culture in this great project!

WhereCampEU2011 – the best bits

Last weekend I attended the 2011 edition of WhereCampEU, held this time in sunny Berlin. It was a great conference, altough smaller than previously in London, but with more diverse presentations than last year’s unconference. I also presented our recent work on geoweb usability at the conference, even though we haven’t had a chance yet to do a comprehensive analysis of the user experiments data we collected. I will put online the presentation in due time. Some lively discussions ensued about the nature of OSM and to what extent it should conform to establish practice in terms of UI (established by Google with for example the Search Bar).

Apart from my own presentation, I just want to highlight some of the more interesting presentations here that I attended:

The first morning for me started to get interesting with a good discussion session on spatial databases, organised by this guy, leading with the definition of theirnecessary characteristics (does a spatial database need to handle projections!?!). The discussion in my opinion showed still a deep distinction between different application domains (this is obviously a continium):neogeographers who want lean, fast spatial databases and are happy with minimal spatial support functions, versus paleotards who want comprehensive entreprise class spatial databases loaded with advanced spatial features such as topological operators, comprehensive projection support and metadata handling… . These two extremes in my opinion needn’t be opposites, but the challenge for future spatial databases will be implementing a complete set of spatial functionalities while remaining, small, nimble and user friendly!

Before our own presentation, Tim Waters from Geocommons gave an indepth demo of the new features of their 2.0 platform. Geocommons to me now stands as one of the best examples of a new generation of advanced geoweb applications, dangerously (for traditional GIS vendors?) coming closer to fully featured GIS app in the cloud. Geocommons now features a complete set of thematic mapping controls, allowing good cartographic prinicples in webmapping. One thing that struck me as something obvious, yet innovative is their use attribute data histograms to guide users as to the choice of thematic formatting. They also now allow users to store, display and analyse very large datasets with great performance, enabling users to go beyond visualisation to analysis of their data ( notably they now implement a set of topological operators). Again, given the advanced abilities of Geocommons, they had to solve a lot of usability challenges, which we would like to investigate further!

The second day came with a set of more advanced technical discussions, most notably for me a discussion session on differences between webmapping frameworks (nicely captured in this whiteboard). We first established that altough there are other libraries, for most geoweb developers, the choice really comes down to Google Maps API vs Openlayers (on its own or inside a UI framework such as  GeoExt or MapQuery). I won’t go into much detail here, as thediscussion and its outcomes have been discussed by both people in the session, as well as members of the OpenLayers team.

Lastly, the conference closed with a very thoughtful presentation by Martjin van Exel on his initiative for the development of an API dedicated to historic OpenStreetMap data. In his presentation, he justified the development of a dedicated separate database and API from the main OSM database, based on some deficiencies of the current OSM data model, for example the fact that the versioning approach doesn’t catch all edits on a given object. Another challenge is the classification of OSM edits according to changes in ground truth, or simply refinements of the same data. Again, Martjin and his collaborators explain this all much better than myself.