Two-handed direct interaction with ARTootKit

A mobile augmented reality system for 3D interaction requires an easy to use, interactive input device. In our work on the Studierstube project, we had long-term experience with two-handed direct manipulation interfaces based on tracked props. However, for a mobile setup, props are no longer appropriate as they permanently occupy the user's hands and prevent the user from performing everyday tasks such as opening doors. Instead, we resorted to the common tool which is very intuitive to use and can be applied for nearly all interactions: our hands. A big advantage of hand based interaction is the intuitive use of gestures such as pointing, grabbing or stretching.