Mark Perry and Caroline Shangar SISCM, Brunel University contact: mark.perry@brunel.ac.uk

1. Marked SpacesInteraction design and sensor integration for ubiquitous location-based messaging and communication Mark Perry and Caroline Shangar SISCM, Brunel University contact: mark.perry@brunel.ac.uk

2. Communication in place • Many common instances of space in communication • notes on fridge doors and colleagues’ desks, paper pushed under doors, pinned up in social areas for viewing at leisure • other instances where desirable (e.g. the bedtime SMS) • Location has an important role to play • comm’s technologies have largely failed to address this • “anytime, anywhere” vs. “now, here” • current communication and information is tied to devices, not places and things • e.g. email, digital music and photographs, etc.

3. Previous work • Commotion (e.g. Schmandt, et al., 2000) • voice-based interaction on GPS platform • simple functionality: to-do lists, augmented with limited location-based information services (context-aware messaging) • Geonotes (e.g. Espinoza et al. 2001) • focus on volume problems in spatial messaging • based just on a single platform (GPS or Wireless LAN) • Urban Tapestries (e.g. Lane, 2004) • situated, public annotations, to build ‘urban histories’ • map-based interaction, focus on ‘place’ • user interaction simplified for the task with little user customisation • All just stationery ‘locations’, all single sensor types

4. Designing to mark space • our goal: • not just locating in, but actively marking space • the space around things, as well as Cartesian space • utilise notion of proximity: ‘on’, ‘near’ or ‘around’ • user-centred perspective • development efforts focus around use and usability

5. Interaction and sensor specificity • Three key granular areas of coverage • different capabilities and constraints • together - rich set of infrastructural resources allowing determination of a device’s location at a different exactness • Microspatial (e.g. RFID tag) • coverage of a few cm to metres - precise sensitivity • un-powered, and allow ‘fit-and-forget’ placement • Mesospatial (e.g. ultrasound beacons/Bluetooth) • coverage of several metres (<5-100metres), powered • signal blocked by structures, allowing room-level sensitivity • Macrospatial (e.g. GPS) • Accurate to approx. 3-100 metres, powered • carried by the user, not embedded

6. Bluetooth Bluetooth RFID RFID <Sender: james> <tag: john’s mobile> remember to speak to John - he’s got your briefcase with him! <Sender: caroline> <tag: no-name> Book due back in the library on the 24th Feb 2005. Check out the reference to UbiNet! ‘Relative’ sensors (e.g. RFID, B/T)

7. <Sender: jim> <tag: grid-reference> ha, ha! get this! <device plays music: School’s out for the summer!> ‘Absolute’ sensors (e.g. GPS) GPS tagged ‘boundary’ around school (an X,Y co-ordinate + n metres)

8. 3 key research elements • understand the use of space in messaging activity • support user needs • mesh with current practices • prototype technical sensor/messaging infrastructure • integrates a variety of sensors • into a single, unified system • develop interaction techniques • lightweight (think SMS) • interactionally integrated (multi-sensor) • personalisable

9. Understanding space • …actually, understanding spatial communication • in particular, asynchronous messaging • little understanding of the role of space in communication: • why leave messages in spaces; what level of location specificity is important; how are situated messages made visible? • need to examine current practices and values • role of spatial messaging in co-ordination and collaboration: • communication doesn’t occur in a vacuum • how do people use messages to communicate and maintain relationships? • and communication breakdowns as current practices fail

10. Interaction design • interaction model: text ‘tagging’ by Graffiti artists • ‘sprayed’ onto people, places and things • extended to ‘media tagging’ (voice recordings, photographs, music) • sensitivity at different levels of precision • how-to-do messaging at different target proximities… • …on an integrated system - with a single user interface? • interaction designer’s task: • low-effort message placement and retrieval • allow users to utilise the different resources and constraints that the different sensors offer • without requiring a deep understanding of underlying technologies

11. a complex design syntax! (for sender) …compare to SMS… present user with list of available sensors menu selection: sensor type, name, other details option <select location/sensor> select <create new message> menu selection select media type create message menu selection, send is the first option option <send> select recipient/s end

12. Interaction design issues… • Questions - how to do: • targeting (sender’s selection of a communication ‘space’) • addressing (how can spaces/sensors be named/identified? as mobile or static? as personal or situated?) • filtering (which messages are relevant to this recipient?) • navigation (how to search through several messages?) • message editing (how to manipulate message settings, e.g. editing message duration or deletion of old messages?) • system personalisation (how to configure the system for ongoing needs?) • …compounded by the constraints of developing on a handheld/small screened device.

13. Summary… • answer question: why might marking people, places and things be useful? • how adopted in current patterns of activity, or appropriated for new reasons? • what values might this form of communication hold for users? • where might it fit into our current communications ecology? • how to achieve this design is a non-trivial task! • its not just a matter of building the infrastructure… • …how can it be made useful and usable?

14. sensors ‘ping’ back a unique identifier which connects to the remote message repository Simplified architecture messages and related ids messages received messages, devices in the area (ids) location data Link Processor messages, related ids location request

15. High level architecture location co-ordinates e.g. GPS location info location request device search sensor poll e.g. B/T unique sensor id unique sensor id tag id sensor poll e.g. RFID