Command Element

Description

Modifies a flexible body element.

Format

<Body_Flexible

         id                   = "integer"

         label                = "string"

         is_user_damp         = " { True | False } "

    {

         cdamp_expr           = "string"

    |

         usrsub_dll_name      = "string"

         usrsub_param_string  = "string"

         usrsub_fnc_name      = "string"

    }                                

         rigidified           = " { True | False } "    

/>  

Attributes

id

Element identification number (integer>0).

This is a number that is unique among all Body_Flexible elements.

is_user_damp

Changes how the damping coefficient for each mode is specified.

A value of TRUE indicates that the damping is specified using either an expression or a user defined subroutine.  

A value of "FALSE" causes MotionSolve to ignore the damping expression or user-defined subroutine data provided in the Body_Flexible element and instead, use the damping values specified in the Reference_FlexData element.

cdamp_expr

Modifies the state dependent expression used to define the damping coefficient for each mode. Use this parameter only when is_user_damp = "TRUE". Any valid run-time MotionSolve expression can be provided as input.

usrsub_dll_name

Changes the path, name, or both for the shared library that contains your user subroutine.  MotionSolve uses this information to load the user subroutine specified by usrsub_fnc_name in the library at run time.  Use this keyword only when is_user_damp = "TRUE".

usrsub_param_string

Changes the list of parameters that are passed from the data file to the user written subroutine. Use this keyword only when is_user_damp = "TRUE".

The syntax for this attribute is:

usrsub_fnc_name

Modifies the name of the user subroutine function specified in the model element.

rigidified

Converts the flexible body to a rigid body.

The default value for this flag is rigidified = “FALSE”.

Comments

Example

The following example illustrates the use of the <Body_Flexible> command element to modify the damping of a flexible body defined in the model:

<Body_Flexible

    id                  = "30102"

    cdamp_expr          = "IF(FXFREQ-100:1.0,1.0,1.0)"

/>

Command Element

Description

Modifies the damping for a FLEX_BODY element.

Declaration

def FLEX_BODY(id, LABEL="", QG=[], REULER=[], VX=0.0, VY=0.0, VZ=0.0, WX=0.0, WY=0.0, WZ=0.0, VM=0, WM=0, MASS=0.0, IP=[], CM=[], RIGIDIFIED=False, CRATIO="", ROUTINE="", INTERPRETER="", SCRIPT=""):

Attributes

id

Element identification number (integer>0). This number is unique among all the FLEX_BODY elements.

LABEL

Modifies the name of the FLEX_BODY element.

CRATIO

Modifies the state dependent expression that defines the damping coefficient for each mode. Any valid run-time MotionSolve expression can be provided as input.

OR

Modifies the list of parameters that are passed from the data file to the user defined subroutine. This attribute is common to all types of user subroutines and scripts.

ROUTINE

Modifies the alternative name for the user subroutine DMPSUB.

INTERPRETER

Modifies the interpreted language that the user script is written in. Valid choices are MATLAB or PYTHON.

SCRIPT

Modifies the path and name of the user written script that contains the routine.

Comments

See Body_Flexible

Example

The example below demonstrates a modification on a FLEX_BODY.

FLEX_BODY(30102, CRATIO=" IF(FXFREQ-100:1.0,1.0,1.0) ")