User-friendliness may improve by adapting user-interfaces to the perceptualmotor skills of human. For this, AR has the advantage over desktop computers and VR that it allows for an interface that is graspable. The advantage of having separate input devices for different functions is that these input devices become representatives for these functions. This will help display the structure of the interface's functionality and to emphasize the difference between functions.
In this paper the ideas for a design of such a graspable user-interface were described. Currently these ideas are being implemented in a working prototype. Future research will focus on comparing non-graspable interfaces e.g. menu based on structures, where functions are differentiated only through the selection of a menu item, with graspable user interfaces, where functions are differentiated through actions and tool selection.
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