vCOG()
velocity of the center of gravity for a given MOVE-flag
[ ... vCOG(i,$MOVEFlag$) ... ]
i = 1,2,3 (only applies for body of type
%MOVE_rigid% !) :: yields the x-, y-, z-component of the velocity of the center of gravity for the given
$MOVEFlag$, respectively.
i = 4 (only applies for body of type
%MOVE_MassSpringDashpot% !) :: yields the length change rate (velocity of compression/expansion) only at each MF timestep .
i = 5 (only applies if body is of type
%MOVE_MassSpringDashpot% !) :: yields the length change rate (velocity of compression/expansion) also at each MKS sub-timestep.
$MOVEFlag$ is directly associated to all boundary elements carrying this
MOVE-flag.