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Participatory Urban Sensing: Vision Video

We are pleased to announce our new video piece that envisions how communities can use everyday mobile phones to gather data about things that are important to them. This vision is being made into reality right now by the center's researchers, who are working on projects such as the Personal Environmental Impact Report (PEIR).


This year, the urban sensing project became a primary application research area, motivated by the widespread proliferation of mobile phones with increasing capabilities enabling them to act as more than a person-to-person communication medium.  Mobile devices are becoming more capable of capturing, classifying and transmitting image, audio, location and other data, interactively or autonomously.  With appropriate system architecture, they can act as privacy-aware sensor nodes and location-based data collection instruments.  Network-connected mobile handsets will be embedded sensors near the ultimate elusive subjects: people and their built environments. These sensors are under their owners’ control and always on. Leveraging them effectively and conscientiously requires models prioritizing user participation in sensing.  Thus, initial research has focused us on howhigh-density sampling coverage over a wide area can be achieved by ad-hoc federations of mobile phones that form a programmable sensing system with opportunistic human-in-the-loop mobility and actuation. 

By involving people in defining and participating in their own data collection, this approach to sensing can address significant unmet challenges in large-scale data collection, from dietary intake assessment in large populations to geotagged audio documentary that gathers the “sounds of the city” for cultural experience or noise pollution assessment.  CENS was an early partner in the Nokia SensorPlanet program, which provided over 250 mobile phones and service in 2006-7 for this research. Currently, microphones and imagers on these mobile handsets can record environmental data; in the future, other sensors will be integrated or connect wirelessly. Cell tower positioning, GPS and other technologies can provide location and time-synchronization data. Wireless radios and onboard processing enable human interaction with both local data processing and remote servers.

Network architecture research.  Sensing with mobile nodes, in collaboration with their owners/operators, requires new algorithms and software mechanisms, because physical inputs and the location of fixed and moving devices become critical data context. Network-level selective sharing mechanisms are needed to enable sharing of data in a controlled way while respecting the privacy of those being sensed. Capabilities envisioned include context verification and resolution control; they are new network primitives to be implemented at the access point and router level. Network-attested location and time are crucial for urban sensing, where they may be equally or more important to data credibility than the gatherer’s identity. The more credible space-time context is, the more useful the data for decision-making and the better “grassroots” or widely-distributed mobile sensing works. Context beyond what the network itself can measure also increases the utility of sensor data. It includes, for example, sensor orientation, measurements made with other sensing modalities and by other nearby sensors. However, the publisher—especially one carrying a mobile device everywhere with them—may not wish to reveal too much, and thus also requires network functionality to support some user control of external context. Research in this area, as well as consideration of the necessary explicit, public and globally reachable naming, discovery, dissemination and aggregation services, is supported by NSF NeTS-FIND and Cisco Systems.

Fig 1Applications: Public Health, Urban Planning, Expression. Many public health applications exist for participatory urban sensing: opt-in activities could be initiated by individuals and organizations to evaluate and support care regimens, gather data for retrospective analysis of chronic and environmentally-affected health issues, and generally collect a wide range of high-fidelity health statistics.  Autonomously captured, geotagged, and selectively shared activity pattern information could help chronic patients and their doctors link environmental factors with symptoms, while explicit guided data gathering offers better compliance detection, timely trend and anomaly analysis, patient reminders and data quality feedback. To begin exploring this area, we developed an NIH proposal with the UCLA School of Public Health and Geffen School of Medicine. The proposed DietSense is a scalable, HIPAA-compliant participatory sensing system enabling health professionals to use existing mobile phones to assess dietary intake for populations of larger size, over longer time periods, with increased fidelity and reduced bias, and at higher spatio-temporal resolutions than current methods.

Core technologies enabling trustable ad-hoc observing applications at the metropolitan scale can also support significant urban planning interests. For example, distributed sound level measurement and basic sound classification can provide quality of life metrics and proxies for information on transportation near neighborhoods. Our approach suggests such data could be gathered by a simple service running on citizens’ mobile devices, gathering and publishing basic statistics on ambient sound at regular intervals, with appropriate context checks. Citizens could initiate and participate in documenting noise levels, using selective sharing mechanisms to configure sampling and resolution acceptable for network verified context tagging of location and time.  A pilot is planned with the UCLA Center for Neighborhood Knowledge in Summer 2007.

Finally, CENS is collaborating with the UCLA Center for Research in Engineering, Media and Performance (REMAP) to explore cultural applications in Los Angeles. REMAP recently established a formal partnership with California State Parks in 2006 to experiment with new uses of technology for interpretation of history and its connection to contemporary life, in the new Los Angeles State Historic Park.  Technologies being developed by CENS for participatory sensing, including geotagged image and audio capture and analysis, provide unique tools for community participation in documenting history, contemporary identity, and neighborhood assets.