User`s guide

Using CAD Models with the Simulink 3D Animation Product
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For converting such rotations into the VRML format, use the Rotation Matrix to VRML
Rotation block found in the Utilities sublibrary of vrlib.
The objects' positions and rotations are treated differently depending on the virtual world
hierarchy:
• When all parts in a Simulink model are defined in global coordinates, and the virtual
world has a flat structure of independent objects, use the following positions and
rotations.
Object positions Send to VR Sink all positions in global coordinates.
Object rotations Send to VR Sink all rotations in global coordinates, with
center of rotation defined as the coordinate system origin. (As
the default center of rotation of VRML Transform objects is
[0 0 0], it is usually not necessary to define it for each part
in the VRML file.
• When all parts in Simulink model follow hierarchical relations, and the virtual world
has a nested structure, use the following positions and rotations.
Object positions Send to VR Sink all positions in local coordinates (relative
to their parents or predecessors in the object hierarchy). For
example, send the robot’s tool position relative to the robot’s
hand.
Object rotations Send to VR Sink all rotations in local coordinates (relative
to their parents or predecessors in the object hierarchy). For
example, send the robot’s tool rotation relative to the robot’s
hand.
To visually match the positions of joints between objects,
it is usually necessary to coincide the center of rotation
defined in the virtual world with the center of rotation
defined in the Simulink model, as joints between parts are
usually positioned not in the origin, [0 0 0], of the parent’s
coordinate system.
To define a center of rotation different from the default value,
[0 0 0], define the center field of the child's Transform
node in the VRML file. For example, define the robot’s tool