Game Development Reference
Figure 8.2 Haptic interface for virtual reality. (Illustration: F. Vigouroux/CEA-advantagesLIST, with
with internal reaction (as well as to portable interfaces), which provides more free-
dom of movement; however, its drawbacks include the weight of the mechanism
that is non-compensable and the overall dimensions around the body;
the mechanism can also be fastened to a fixed base (for example, generic haptic
interface placed on the ground). We then refer to force feedback with exter-
nal reaction (as well as to fixed interfaces), that have opposite advantages and
disadvantages (Fuchs et al., 2003).
Based on the mechanical structure, we can distinguish between several categories
in each interface type, which can be serial (with a form identical to a manipulator robot
arm) or parallel (with a form identical to parallel robots). The latter interface category
benefits from large stiffness as well as the option to place the robot actuators on the
fixed support, which limits the inertia felt by the user when he handles the interface.
However, it has a limited work space in relation to the dimensions of the interface,
mainly in orientation.