Rollo developed from a project aimed at creating an interactive object with repetitive elements for a child aged 4 to 8 years. It was a collaboration between three university students and a 7-year-old child co-designer. The structure needed to be engaging, to require minimal adult supervision, and to be less than half a cubic metre in size. The principles of product semantics (e.g., light/dark, opaque/transparent and inside/outside) were to be used to create a contrasting and more engaging product. Finally, the object was to be directly influenced by the co-designer as the primary source of feedback. By the end of the co-creation process, a modular run ushered a marble through a customizable course. A key feature was that the marble path can travel in and out of view and back again, compelling users to change their own viewing position to follow the marble on its journey. The appearing/disappearing dynamic creates a renewable element of novelty and surprise.
