Category Projects


LiquidText is a multi-touch document manipulation system that provides a uniquely flexible environment for active
reading — the focused, critical reading we do when we highlight, annotate, flip between pages, compare documents, etc. To provide this more flexible, fluid way to interact with documents, we developed a high degree-of-freedom user interface, where the reader can freely and precisely control both the visual representation and the navigational structures of their content. What this means is that things that used to be hard, like comparing several sections of a long text, creating annotations that refer to many parts of a text at once, or aggregating your annotations together without losing their context, are now easy.

Watch a quick demo here, or learn more at

Collaborative Network Troubleshooting

Despite rapid adoption of networked computing in the home, home networking setup and maintenance tasks are extremely difficult for many people. Recently, the Human-Computer Interaction research community has had an emerging interest in studying the user experience (e.g. usability problems) associated with networked computing and AV equipment in the home. However, this community has little empirical data about the help-seeking practices of people who are experiencing trouble setting up or fixing their networked equipment. We are collecting data about help-seeking by (1) automatically analyzing the content and context of popular online help forums and (2) conducting a set of focus groups about help-seeking practices. Through this research, we are discovering which aspects of home network setup and maintenance householders find most troubling, as well as how they seek help to resolve these problems.

Technology and the Homeless

Technology is all around us, and while we consider new and novel uses for mobile and ubiquitous computing it is also important to consider how these kinds of technologies affect members of our society who do not have access to them. The aim of this work is to understand how technological innovations might be deployed to the urban homeless and to the institutions that support them.


The inSpace project is an interdisciplinary collaboration with Steelcase. The project brings together researchers with experience ranging from human-computer interaction, interaction design, software development, industrial design, furniture and interior design, and architecture. A central goal in this research partnership is to understand how these different layers should be co-designed.

Our current space includes a number of technical artifacts that work together to support collaboration, including a table with integrated sensing and ambient feedback, a shared wall display supporting multiple simultaneous users, and a collection of storage and infrastructure services for communication, wused in the space.

Values in Design

Values play an integral role in design: they inform the kinds of trade-offs the make when considering different solutions; they create a basis for assessing a particular artifact or system may fit into their lives; and they are an important part of negotiating common understanding in collaborative design settings. This project focuses on the various ways values become expressed through design of artifacts and systems.

Window Scape

WindowScape is a task oriented window manager designed to help people access windows as groups, as well as organize and manage individual windows more easily. WindowScape allows windows to be miniaturized down to thumbnail size and organized by the user. This temporally stable layout of miniatures allows people to leverage their spatial memory when searching for a window. To enable people to switch between groups of windows, WindowScape builds a timeline of window configuration states, and provides techniques to rapidly return to those prior configurations. In effect, these history states act as implicit, post-hoc window groups. It is implicit because the user never has to explicitly choose whether a given window belongs in a particular set. These decisions are only indirectly made through the history states the user decides to access. The groupings are post-hoc because the user does not have to make a priori decisions about where a window belongs. They can instead defer the decision until the last moment when they actually need to use access the group. WindowScape also offers interesting techniques for accessing obscured windows while largely maintaining a stable display image, as well as enabling keyboard navigation among arbitrarily arranged objects.

Home Networking

Most research in networking has focused on “traditional” issues, such as bandwidth, scalability, latency, and so forth. What if we were to look at networking instead from a human-centered perspective? What traits would we care about then? Most likely, things like understandability, maintainability, evolvability, and installability.

Our lab is engaged in a number of projects aimed at what we call human-centered networking. Through these projects we are seeking to understand the causes of digital complexity in the home and how householders cope with these difficulties, as well as develop new tools and technologies to improve the experience of home networking.

Our empirical work in this space includes in-home qualitative investigations focused on understanding users’ needs and practices, analyses of householder-generated sketches of their home networks to uncover end-users’ conceptual models of networking, the development of a range of “ground truth” datasets of home network performance and behavior, and a series of studies aimed at understanding the social dynamics of network use in the home.

We are also engaging in technical work aimed at creating a set of tools, infrastructures, and interaction techniques that provide a better match for users’ needs and practices. These projects include the development of visual tools for home network management, the creation of new infrastructure components (routers and access points) for the home network intended to improve the user experience for users, and exploration of new management protocols effective in the home network context.

Usable Security

The Pixi Lab is the host of the Tiger Team Student Design Competition for Usable Security. Held 2005-2007, this competition allows two-person student teams (representing both HCI and Security) to compete for funding to develop novel projects that address challenges of usable security. The competition has been supported generously by Symantec, IBM Internet Security Systems, and Google.