Sam Nemeth and and Lars Erik Holmquist will present the paper Conjoint Control: A Practical Approach to Implementing Physical Interfaces in Real-World Settings at HCI International 2025 in Gothenburg, Sweden (open access version here).
The study concerns how to implement physical interfaces, often called tangible user interfaces (TUI), in real-world settings. Such interfaces are in many ways more difficult to implement and maintain than purely software-based graphical interfaces, and this is one of the reasons that they are almost exclusively present in lab settings, despite having documented advantages compared to screen-based interfaces. To support the development of physical interfaces we created a set of guidelines we call Conjoint Control. The approach stresses the use of communities and off-the-shelf hardware and software, as well as an interplay between the designer and the intended users.The guidelines were applied in a real-world use case where we created and deployed a physical interface in a real-world office setting. We were given the task by the management of a building to design a system to manage a reception desk from a remote location – a “telepresence receptionist”. By following the process of Conjoint Control, we were able to design, implement and deploy a system that was used by the staff for over a year.