Flexprep Usage

To find the command line arguments for flexprep, choose from one of the following:

•	In UNIX, type flexprep at the command line prompt.

•	On PC, double-click on flexprep.exe in the bin directory.

•	Navigate the Flexbody Prep dialog through Finish and observe the command line arguments.

You can also copy these command line arguments to a script file (UNIX) or BAT file (PC) to easily repeat the procedure.

Note	flexprep checks the environment variable, TMP. You can set TMP to any directory large enough for the TMP files if it is a flexprep run.

usage: flexprep <source>.pch <target>.h3d [-<units>]

// Translate NASTRAN punch file made with ADAMS' DMAP into
ALTAIR h3d file.

flexprep <source>.mnf <target>.h3d [-<NO_UNIT_CONV>]

// Translate ADAMS mnf file into ALTAIR h3d file.

flexprep <source>.h3d <target>.mtx [invar_option]
[+node_list] [+mode_list] [-<units>] [-<mirror option>]

// Translate ALTAIR h3d file into ADAMS mtx file for
flexible bodies.

flexprep <source>.h3d <target>.h3d [-<mirror option>]

// Translate ALTAIR h3d file into its mirrored (symmetric)
part with respect to the mirroring plane.

flexprep <source>.<bdf|nas|dat|fem|blk> <target>.h3d
-ospath:<dir path> <mode_type_option> <+interface_node_list>
[upper_freq [HZ]] [-<units>] [-<stress>]

// Perform CMS using the NASTRAN Bulk Data file and write
results into ALTAIR h3d file. OptiStruct required.

flexprep <source>.h3d <target>.fdf [+mode_list] [-<units>]

// Translate ALTAIR h3d file into DADS fdf file for
flexible bodies.

examples: flexprep xxx.pch yyy_flex.h3d -METER -KILOGRAM_FORCE

Translate xxx.pch with the optional units to yyy_flex.h3d.

The default is KILOGRAM, MILLIMETER, NEWTON, and SECOND

flexprep xxx.mnf yyy_flex.h3d

Translate xxx.mnf to yyy_flex.h3d. (units included in mnf
file)

flexprep xxx_flex.h3d yyy.mtx TTTTTTTTF +1+1001 +7:9+11:15 -
METER

Translate xxx_flex.h3d to yyy.mtx with node 1, node 1001 and
modes 7, 8, 9, 11, 12, 13, 14, 15 selected.

Unit of the resulting mtx file can be specified (as METER in
his example) in the options list

The default is KILOGRAM, MILLIMETER, NEWTON, and SECOND

In general, mode 1-6 are the rigid body modes so the valid
mode number should start from 7.

flexprep xxx_flex.h3d yyy.mtx TTTTTTTTF +ALL +ALL -METER -
MIRROR_XZ

Include all nodes and modes (rigid body modes will be
automatically excluded)

Use XZ plane (in basic coordinate frame) as the mirroring

plane and translate to mtx file the mirrored part.

flexprep xxx_flex.h3d yyy_flex.h3d -MIRROR_XZ

Use XZ plane (in basic coordinate frame) as the mirroring

plane and create the mirrored part of the original one.

flexprep xxx_flex.h3d yyy.mtx TTTTTTTTF +I+6:8+10 +ALL -METER

If interface nodes block exists in the h3d file (e.g. read

from mnf file interface

node block or if the h3d is from flexprep/OptiStruct analysis),

then interface nodes will be selected, plus additional non-

interface nodes (non-force bearing node, or sensory nodes).

Suppose the interface nodes recorded in h3d file are 1 and

1001, the above command will select nodes 1, 1001, 6, 7, 8,

and 10.

flexprep xxx.blk yyy_flex.h3d CB +1+1001 10 -STRESS

Compute Craig-Bampton modes with nodes 1 and 1001 as the

interface nodes and 10 eigen modes.

Orthogonalize the mode set and write the results as well as

the element stress modes into yyy_flex.h3d file.

flexprep xxx.blk yyy_flex.h3d CB +1+1001 1000.0 HZ

Compute Craig-Bampton modes with nodes 1 and 1001 as the

interface nodes and eigen modes up to 1000 HZ.

Orthogonalize the mode set and write the results into

yyy_flex.h3d file.

flexprep xxx.blk yyy_flex.h3d FF +1+1001 1000.0 HZ -STRESS

Compute Free-Free eigen modes with frequency up to 1000 HZ.

Write the results as well as the element stress modes into

yyy_flex.h3d file.

flexprep xxx.blk yyy_flex.h3d FR +1+1001 10

Compute 10 free-free eigen modes and frequency-response

attachment modes with nodes 1 and 1001 as the interface

nodes.

Detect and remove possible dependent modes, orthogonalize the

mode set and write the results into yyy_flex.h3d file.

mass unit: GRAM, KILOGRAM, MEGAGRAM, POUND_MASS, SLUG, OUNCE_MASS, KPOUND_MASS

length unit: INCH, FOOT, MILE, MILLIMETER, CENTIMETER, METER, KILOMETER

force unit: OUNCE_FORCE, POUND_FORCE, KPOUND_FORCE, DYNE, NEWTON, KILOGRAM_FORCE, KNEWTON

time unit: MILLISECOND, SECOND, MINUTE, HOUR

Note	Space in the .fem and .h3d file paths is currently not supported on Linux and Mac OSX.