Members of the PD-Net consortium showed a couple of demos at the 2013 ACM International Joint Conference on Pervasive and Ubiquitous Computing (Ubicomp 2013).

Control and Scheduling Interface for Public Displays

Social media platforms such as Flicker, Twitter, Instagram, and Facebook have opened up new possibilities for providing content on large public displays. Integrating interactive elements in a public display, such as (virtual) Keyboards and Webcams, can additionally stimulate in-situ content production. Both social media content and such in-situ content are cheap to produce, always fresh, and potentially community sourced, thus increasing relevance for passersby. However, not all social media applications and content entries may be appropriate in a particular display setting and showing user contributed content on public displays requires new forms of content control and scheduling. In this demo we show: 1) a control interface for display owners to manage the overall behaviour of their displays, and 2) post-moderation mechanisms for controlling and removing potentially inappropriate user contributed content from public displays displays. The control interface and moderation mechanisms are designed for a university environment and were inspired by two short pilot test deployments and a focus group with the university socials.

Supporting Interaction in Public Space with Electrical Muscle Stimulation

As displays in public space are augmented with sensors, such as the Kinect, they enable passersby to interact with the content on the screen. As of today, feedback on the user action in such environments is usually limited to the visual channel. However, we believe that more immediate and intense forms, in particular haptic feedback, do not only increase the user experience, but may also have a strong impact on user attention and memorization of the content encountered during the interaction. Haptic feedback can today be achieved through vibration on the mobile phone, which is strongly dependent on the location of the device. We envision that fabrics, such as underwear, can in the future be equipped with electrical muscle stimulation, thus providing a more natural and direct way of haptic feedback. In this demo we aim to showcase the potential of applying electrical muscle stimulation as direct haptic feedback during interaction in public spaces in the context of a Kinect-based game for public displays.

  • I. Elhart, N. Memarovic, M. Langheinrich, and Elisa Rubegni, “Control and Scheduling Interface for Public Displays,”The 2013 ACM Conference on Ubiquitous Computing Adjunct Publication, 2013. [Bibtex][PDF]
  • M. Pfeiffer, S. Schneegaß, and Florian Alt, “Supporting Interaction in Public Space with Electric Muscle Stimulation,” The 2013 ACM Conference on Ubiquitous Computing Adjunct Publication, 2013. [Bibtex][PDF]


Nigel Davies, Rui Jose, Nemanja Memarovic, Ivan Elhart, and Sarah Clinch organize a workshop on developing publications for public display networks. With significant reductions in the cost of large LCD screens, public displays are proliferating in urban spaces. It is not hard to imagine that they will soon be networked and connected over the Internet, constituting a novel and powerful communication medium pervasive display networks open to a wide range of applications and content. The aim of the workshop is to bring together experts from a variety of domains, i.e., UbiComp, HCI, Software Engineering, User Experience, and Public Displays to exchange ideas and discuss opportunities and challenges in creating applications for pervasive display networks. Overall, the goal of the workshop is to setup a meeting point for the people working on pervasive display networks as well as to create a common understanding and set the goals and challenges for further research on the topic of developing applications for pervasive display networks.

Workshop website:

The Third International Symposium on Pervasive Displays will take place in June 2014 at the University of Copenhagen in Copenhagen, Denmark. The event will bring together researchers from various disciplines with a common interest on the opportunities and challenges raised by the emergence of pervasive display systems as a new communication medium for public and semi-public spaces. As a targeted topic venue, Pervasive Displays offers participants a unique opportunity to network with a diverse but focused research community, resulting in an extremely lively event with all the energy and excitement that characterizes the emergence of a new research community. Previous Symposia were organized by the University of Minho in Porto, Portugal (2012) and by Google, Mountain View, CA, USA (2013).


On June 4-5 2013, the Second International Symposium on Pervasive Displays (PerDis’13) was hosted by Roy Want and Bill Schilit at Google in Mountain View (US). During the conference a set of 27 exciting papers was presented, 6 including authors from PD-Net.

  • F. Alt, S. Schneegass, M. Girgis, and A. Schmidt, “Cognitive effects of interactive public display applications,” in Proceedings of the 2nd ACM International Symposium on Pervasive Displays, New York, NY, USA, 2013, pp. 13-18.
  • N. Memarovic, K. Cheverst, M. Langheinrich, I. Elhart, and F. Alt, “Tethered or free to roam: the design space of limiting content access on community displays,” in Proceedings of the 2nd ACM International Symposium on Pervasive Displays, New York, NY, USA, 2013, pp. 127-132.
  • N. Broy, F. Alt, S. Schneegass, N. Henze, and A. Schmidt, “Perceiving layered information on 3D displays using binocular disparity,” in Proceedings of the 2nd ACM International Symposium on Pervasive Displays, New York, NY, USA, 2013, pp. 61-66.
  • S. Clinch, N. Davies, A. Friday, and G. Clinch, “Yarely: a software player for open pervasive display networks,” in Proceedings of the 2nd ACM International Symposium on Pervasive Displays, New York, NY, USA, 2013, pp. 25-30.
  • R. José, J. Cardoso, F. Alt, S. Clinch, and N. Davies, “Mobile applications for open display networks: common design considerations,” in Proceedings of the 2nd ACM International Symposium on Pervasive Displays, New York, NY, USA, 2013, pp. 97-102.
  • Marc Langheinrich, Albrecht Schmidt, Nigel Davies, and Rui José (2013): A Practical Framework for Ethics – the PD-Net Approach to Supporting Ethics Compliance in Public Display Studies. In: Proceedings of the Second International Symposium on Pervasive Displays (Mountain View, CA, June 4-5, 2013). PerDis 2013. ACM, New York, NY.

All papers can be found on the publication page.

The PerDis Symposium series will continue in 2014, being hosted by Sebastian Boring in Copenhagen. Aaron Quigley will be the TPC chair.


Information on the PD-Net Ethics Framework are now available on the project website (read more).

Research involving public displays often faces the need to study the effects of a deployment in the wild. While many organizations have institutionalized processes for ensuring ethical compliance of such human subject experiments, these may fail to stimulate sufficient awareness for ethical issues among all project members. Some organizations even require such assessments only for medical research, leaving computer scientists without any incentive to consider and reflect on their study design and data collection practices. Faced with similar problems in the context of the EU-funded PD-Net project, we have implemented a step-by-step ethics process that aims at providing structured yet light-weight guidance to all project members, both stimulating the design of ethical user studies, as well as providing continuous documentation.

Here, we describe our process and our 3 years of experience using it. All materials are publicly available and we encourage other projects in the area of public displays, and beyond, to adopt them to suit their particular needs and to eventually re-share their experiences and material through this website. If you adopt any of the documents presented in your project we would appreciate if you reference our corresponding publication as follows:

Marc Langheinrich, Albrecht Schmidt, Nigel Davies, and Rui José (2013): A Practical Framework for Ethics – the PD-Net Approach to Supporting Ethics Compliance in Public Display Studies. In: Proceedings of the Second International Symposium on Pervasive Displays (Mountain View, CA, June 4-5, 2013). PerDis 2013. ACM, New York, NY.

Rui Jose gave an interview to a Portuguese TV channel, talking about PD-Net. He introduced the open public display network currently being set up in the city of Guimaraes.

The full interview can be found here (in Portuguese).

Members of the PD-net consortium recently contributed a set of articles to an IEEE Computer Issue on Large Interactive Displays.

Reflections on Long-Term Experiments with Public Displays

(A. Friday, N. Davies, C. Efstratiou)

A reflection on the authors’ experiences with public display research—systems built and lessons learned—explores content creation and control, programmable infrastructures, and applications, to offer unique insights for those considering research or practical deployments using this technology.

Find the article here:

Advertising on Public Display Networks

(F. Alt, J. Müller, A. Schmidt)

For advertising-based public display networks to become truly pervasive, they must provide a tangible social benefit and be engaging without being obtrusive, blending advertisements with informative content.

Find the article here:

Open Display Networks: A Communications Medium for the 21st Century

(N. Davies, M. Langheinrich, R. José, A. Schmidt)

Open public display networks could emerge as a new communications medium for the 21st century, but this transformation can only occur if the technology moves from its current, closed model to a new, open one.

Find the article here:

Instant Places Deployment

Instant Places is a novel screen media system that explores new practices for individual publication and identity projection in public digital displays. With Instant Places, people can have an identity representation that allows them to explicitly and systematically manage their presence in public displays. Instant Places has been deployed in several venues in the city of Guimarães and other neighbouring cities and has been providing with feedback about the adequacy of our approach for end users, content creators, and display owners.

A video about Instant Places can be found here.

Currently, there are only few environments available that allow for testing public display applications on an urban scale in the wild. In the context of the UbiChallenge 2011 we developed two services in Oulu, Finland over the course of 6 months. Digifieds (derived from digital classified), is a digital public notice area that allows information to be created, posted and taken away from public displays, either directly or using a mobile phone. The FunSquare service is based on self-generative autopoiesic content assembled dynamically by matching real-time context streams with existing content fragments into localized “fun facts”.

During the  evaluation we were able to gather valuable insights from observations, interviews, and a field trial with regard to content, privacy, and users’ motivations.

We presented our Full Paper on “Designing Shared Public Display Networks – Implications from Today’s Paper-Based Notice Areas” at the Ninth International Conference on Pervasive Computing in San Francisco, US (full paper).

 Large public displays have become a regular conceptual element in many shops and businesses, where they advertise products or highlight upcoming events. In our work, we are interested in exploring how these isolated display solutions can be interconnected to form a single large network of public displays, thus supporting novel forms of sharing access to display real estate. In order to explore the feasibility of this vision, we investigated today’s practices surrounding shared notice areas, i.e. places where customers and visitors can put up event posters and classifieds, such as shop windows or notice boards. In particular, we looked at the content posted to such areas, the means for sharing it (i.e., forms of content control), and the reason for providing the shared notice area. Based on two-week long photo logs and a number of in-depth interviews with providers of such notice areas, we provide a systematic assessment of factors that inhibit or promote the shared use of public display space, ultimately leading to a set of concrete design implication for providing future digital versions of such public notice areas in the form of networked public displays.

Additionally we presented a poster on Digifieds, a digital public notice area (poster).

Public notice areas are nowadays being widely used in stores, restaurants, cafes and public institutions by customers and visitors to sell or advertise products and upcoming events. Although web platforms such as Craigslist or eBay offer similar services, traditional notice areas are highly popular as using pen and paper poses only a minimal barrier to share content. With public displays proliferating the public space and with means to network these displays, novel opportunities arise as to how information can be managed and shared. In an initial step we systematically assessed factors inhibiting or promoting the shared use of public display space and derived design implications for providing a digital version of such public notice areas. In this poster we report on the implementation of such a digital shared notice area, called Digifieds. With an initial lab study we aimed at understanding suitable means of interaction when it comes to creating, posting, and taking away content.