usability issues for non-visual interfaces to gi
DESCRIPTION
by Paul Kelly, Queens University BelfastTRANSCRIPT
The Power of the Image2011
Usability Issues for non-visual Interfaces to
Geographical Information
Presenter: Dr Paul Kelly
Electrical & Electronic Engineering, Queen’s University Belfast
The Power of the Image2011
Outline
• Visual and non-visual interfaces
– “Products”, end users and the role of
the cartographer
• Data requirements for non-visual
interfaces
• Difficulties faced by non-specialists
in using geographical information
• How cartographers can help
The Power of the Image2011
A Visual Interface to GI
What is the product? Who are the users?
What is the role of the cartographer?
Taken from BCS Website, © Stirling Surveys
The Power of the Image2011
My Answers…
The Product
The printed (or otherwise rendered) map
The Users
People (walkers) interpreting the
information contained in the map
Role of the Cartographer
To filter and simplify complex geographical data in order to facilitate its
communication to the users of the map
The Power of the Image2011
Example non-visual interfaces
Distance Sound –“Geiger Counter”
DirectionVibration Patterns
GeoMobile GmbH
The Power of the Image2011
Haptic Belt
OFFIS e.V.
The Power of the Image2011
TactiCycle
• Handlebars vibrate
• Indicates direction
OFFIS e.V.
The Power of the Image2011
Walking Map: Usage Scenarios
1. Cyclist (no hands free)
2. Blind person (accompanied or even alone)
3. Walker in wet weather with no map case
Taken from BCS Website, © Stirling Surveys
The Power of the Image2011
Non-Visual Perceptualisation
CyclistUpcoming gradients
Distance to destination
Blind PersonNearby geographical features – streams, lakes, forests, hillsPerceptualise landscape without seeing it
Path-following if walking alone
Walker in bad weatherDistance, gradients, upcoming turns
No need for anything to get wet
The Power of the Image2011
For non-visual interfaces, what is…
The Product?
The perceptualisations, or the software
that provides them
The Users?
Walkers or cyclists, same as before
Role of the Cartographer?
???
Pessimistic View!
The Power of the Image2011
More optimistically:
The Product
The geographical data that the perceptualisation software uses
The Users
Human-computer Interface (HCI) software developers
Role of the Cartographer
Lots of opportunities!
Filter and simplify complex geographical data for use by HCI developers
The Power of the Image2011
Data Requirements for non-visual interfaces
Vector Primitives
PolygonLineStringPoint
Geometric Queries
– Point-in-Polygon
– Shortest distance to line
– etc.
The Power of the Image2011
Data actually used by HCI developers
Anecdotal evidence from the
HaptiMap European project:
Mostly just self-generated GPS points:
the “waypoint” paradigm
Lunds universitet
The Power of the Image2011
Why? 1 – Unfamiliarity
• Unfamiliar Terminology
What to ask for – a map?
Geographical data?
• Unfamiliar Structure
Point – linestring – polygon model
The Power of the Image2011
Why? 2 – Data Complexity
• Too many different ways of doing the same thing – doesn’t force data providers to consider usability
e.g. ESRI Shapefile has 14 geometry types: Null Shape, Point, Polyline, Polygon, MultiPoint, PointZ, MultiPointZ, etc.
• Datasets often structured with only cartography in mind
e.g. OS VectorMap Local has street names in an entirely separate layer from the streets!
The Power of the Image2011
OpenStreetMap – any better?
XML interface – inefficient and slow, but human-readable → logical structure of data is obvious without formal documentation
Only two geometry types: nodes & ways
Simple key/value freeform text attributes – can nonetheless describe complex relationships
The Power of the Image2011
OpenStreetMap again
Not perfect – e.g. latitude & longitude co-ordinates make geometric operations unnecessarily complex
Advantages of a projected co-ordinate system are missed
But gaining acceptance anyway –convenience of a universal source of large-scale vector data hard to overstate
The Power of the Image2011
Can any lessons be learned?
Strong focus on the XML interface as
the public, usable “face” of OSM
Rendered maps not the only “product”
No need for users to have a GIS in
order to read vector data
Open, usable vector API facilitates
imaginative non-cartographic uses
The Power of the Image2011
Conclusions
Interface between specialist and non-
specialist has been pushed back
Usability of underlying vector data can
sometimes be just as important as
usability of the map
Cartographers’ knowledge of and
focus on data quality, clarity and
usability could really be of benefit
The Power of the Image2011
Ideas in this presentation were developed
from work in HaptiMap, a large-scale
integrating project funded by the European Commission under the 7th Framework
Programme (FP7-ICT-224675).