The AR Workbench: A Complete Co-located Reach-in Mirror-Based ...

Marlon Richert, Master’s Thesis, Friday, 23 February, 2007
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the desk, including a fork, a knife, and a spoon. Frank tells her
that she can touch any of the pieces of virtual cutlery and it will
automatically attach to the real handle she is holding. If she
already has a piece of cutlery on the handle, it will at that point
simply fall off and the new one will attach in its place.
Frank suggests that she uses the virtual knife to cut a piece off
the virtual apple. Carol touches the virtual knife with the real
handle. She makes a slicing motion with the knife thru the virtual
apple and a piece of the apple falls off. Franks then asks Gloria if
she can use the virtual fork to move the virtual piece of apple to
her mouth. Gloria does so and the piece disappears. They then
continue to pretend to eat other items of virtual food.
Table 5 Gloria calibrates the display (visionary scenario).
Participating
actors:
Flow of
events:
Gloria: therapist
4.2 System Models
Gloria has just recently moved her AR workbench to a new room
and needs to recalibrate the display. She puts the video
projectors in place and starts the calibration software. Each
projector now projects a grid onto the projection screen. Gloria
adjusts the projectors until their grids align. She then takes place
behind the work and, while looking through the mirror, takes one
of the motion trackers and places it in turn on the nearest two
corners and the center of where she perceives the reflected
projection to be. Each time she does so, she presses a key on her
PC keyboard. The display is now calibrated and ready for use.
This section details the models that describe the system. Figure 4 represents the
functional model, which describes the functionality of the system from the user’s
point of view. Figure 5 represents the analysis object model, which describes the
structures of the system in term of concepts that are visible to the user.
Figure 4 Functional model of the system (use case diagram).