Unencumbered interface technologies do not, by themselves, constitute an interface. A mapping must exist between the input technology and the system to be manipulated. This mapping must be carefully chosen, because it defines the metaphor that the user is forced use when they interact with the system. The desired level of abstraction, tolerance to interface accuracy and lag, even the prior expectations of the user must be taken into account when designing this mapping.
This section describes several systems that have been built in our lab, each with a distinct interface/system mapping. The focus will be on these interface mappings: how they work with the interface technology, and also how they affect the interactive experience.