Welcome to Adams/Solver Subroutines - Kxcad.net

Input Arguments
Welcome to Adams/Solver Subroutines
id An integer variable that provides the identifier of the FLEX_BODY
statement requesting information from the DMPSUB. From the identifier,
Adams/Solver automatically knows other information (such as the par
argument) available in the corresponding statement.
time A double-precision variable containing the current simulation time.
par A double-precision array of constants taken, in order, from the USER
parenthetical list of the FLEX_BODY statement.
npar An integer variable that indicates the number of constants specified in the
USER parenthetical list. The primary purpose of npar is to provide the
DMPSUB evaluation subroutine with the number of values stored in the par
array.
freq An array of natural frequencies for the modes in cycles per user-defined time.
nmode The total number of modes associated with the FLEX_BODY statement.
h The current integrator step size. This is useful if you are using damping to
prevent integration problems.
Output Argument
cratios An array of damping ratios as a fraction of critical damping. There must be
one value computed for each of the modes.
Examples
To control the modal damping of individual modes using a user-written subroutine, use CRATIO=USER
according to Adams standard practice. The damping ratios for the selected modes are obtained through
a call to the DMPSUB subroutine. For a model using units of seconds for time, this example illustrates:
• 1% critical damping for modes less than 100 Hz.
• 10% critical damping for modes greater or equal to 100 Hz but less than 1 kHz.
• 100% critical damping for modes greater than or equal to 1 kHz.
The following statement defines the constants Adams/Solver is to pass to the DMPSUB evaluation
subroutine:
FLEX_BODY/1, I=101, J=201
, CRATIO=USER(.01,100,.1,1000,1)
For the current example of this subroutine, see dmpsub.f.
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