Shared space is an augmented reality system that allows multiple users to collaborate on the same task. Mark presented several games using Shared Space which were designed to investigate how effective Shared Space was at supporting collaboration and interaction between two users. The system is designed to suppor people working together and does not affect normal interaction. Because the system depends on augmenting a real environment it is not possible to collaborate with geographically remote users. Virtual objects could be overlaid on the panel.
Users can then move the panel to manipulate the object.
Since the pen and panel are physical objects the user gets tactile feedback when the pen touches the panel to make a selection. When moving the user Ulysse attempts to navigate around obstacles and detect collisions between the user's embodiment and artifacts in the Virtual Environment. Ulysse can also be told to manipulate artifacts in the virtual environment. Extending VRML to Support Collaborative Virtual Environments Wolfgang Broll discussed his extensions to VRML to support multiple users. This approach divides artifact behaviour into several catagories each of which is supported by different mechnanisms to provide the best compromise between consistency and interactivity.