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.