Perceptual−Motor Performance Issues in the MagicBoard Scenario

Interfaces which are based on free physical movement within a space (for example, relying on gesture recognition technology) pose many questions for interface designers, some of which are identified in the scenario. One potential advantage for systems such as the MagicBoard, which are based on existing, familiar physical artefacts is that interaction with the board is by means of well developed perceptual−motor skills for writing, or for gestures such as pointing. From this one might conclude that modelling the performance of users with such systems would simply be a matter of applying existing models of human perceptual motor skills. These models certainly give us a starting point, but unless the models have been developed for application in human computer interaction, we must be careful not to not miss possible performance shaping factors introduced by the technology. In the case of MagicBoard, the need of the user to make certain gestures at a speed which the system is capable of following is a very real limitation on the user ́s performance.