Redefines modal damping as a fraction of critical damping. You can specify modal damping using a function expression or a user-written subroutine. To define the modal damping with an expression, follow CRATIO with an equal sign and the expression. The FXFREQ and FXMODE function expression may be useful here.

To define modal damping with a user-written subroutine, follow CRATIO with an equal sign, the character string USER, and the values (r1,[,...,r30] that the Adams Solver (C++) is to pass to the DMPSUB user-written subroutine. If the CRATIO argument is used, it must either be the last argument in the FLEX_BODY statement, or be followed by a backslash (\).

Lists the current values of the FLEX_BODY arguments.

Switches the flexible body representation from MODAL to RIGID or vice versa during the simulation. To enable this option during runtime, the REPRESENTATION argument must have been specified on the FLEX_BODY statement. Note that switching the flexible body REPRESENTATION to RIGID can speed up the simulation, but can result in a loss in fidelity.