Augmenting natural interaction in projective capacitive displays with tangible interfaces

Using tangible user interfaces for improving the interaction with multitouch displays can be very effective, specially in applications whose main users are children. The use of tangible physical objects allows to simplify the graphical interface on the display and at the same time to provide an immediate connection with physical world. In this paper we discuss the use and implementation of tangible interfaces through the use of "fiducial markers" combined with projected-capacitive multitouch displays, and their application within the project i-Theatre. The objective of the i-Theatre project is to develop a new integrated interactive system for storytelling for young children. With i-Theatre, children can create computer stories animating their own imaginary characters using a touchscreen and manipulating a set of physical objects. Currently, it uses external tangibles objects, which interact with the system using various technologies such as RFID and silicon IDs. Adding the use of “fiducial markers” attached to objects allow to enrich the set of tangibles and create new ones that can interact directly with the surface of the capacitive screen.