Of pages and paddles: Children's expectations and mistaken interactions with physical-digital tools

An assumption behind new interface approaches that employ physical means of interaction is that these can leverage users' prior knowledge from the real world, making them intuitive or 'natural' to use. This paper presents a user study of Tangible Augmented Reality, which shows that physical input tools can invite a wide variety of interaction behaviours and raise unmatched expectations about how to interact. Children played with interactive sequences in an augmented book using physical paddles to control the main characters. Our analysis focuses on how knowledge and skills that children have from the physical world succeed or fail to apply in the interaction with this application. We found that children expected the digital augmentations to behave and react analogous to physical 3D objects, encouraged by the ability to act in 3D space and the (digital) visual feedback. The affordances of the paddles as physical interaction devices invited actions that the system could not detect or interpret. In effect, children often struggled to understand what it was in their actions that made the system react.