a device and software system with input and output capability for manipulating real and virtual objects in 3 - dimensional space . the device consists of a six degree - of - freedom mechanical armature that has sensors to determine the location and orientation of a stylus and planar surface . in the input mode , manipulation of the physical armature will result in a corresponding two - dimensional , virtual image of the stylus and surface on a computer screen . the armature also has motors to automatically change the armature location and orientation in order to generate a physical representation in the real world of the location and orientation of a virtual object . the armature is built so that it maintains balance at any location and orientation to statically maintain the armature location and orientation without drifting to a null rest position .