When modeling wind turbines with a multi-body dynamics program called ADAMS®, I need to know the global coordinates and orientation of specific parts.  I usually only know the location and orientation of parts with respect to their adjacent parts.  This means I need to go through several coordinate transformations from the ground up to get a single global transformation matrix.  I then need to find Euler angles that will give me the same transformation matrix.

Doing these multiple transformations is not a trivial task and is virtually impossible to do with a calculator.  This prompted me to write a program to do it for me.  At first, I wrote TRANS to do only orientations, but decided later to add translations.  You can run TRANS in orientation-only mode or do both.

To use TRANS, you simply enter a series of translations (if desired) and Euler-angle rotations.  After each entry, TRANS outputs the current orientation and (possibly) location in the ground coordinate system.  It is quite simple to use and gives virtually instantaneous response on my SGI Indigo2 workstation.

TRANS is of generic use to anyone doing coordinate transformations and is not specific to the Wind Energy industry.  If you would like to use TRANS, you may download its source code.  I wrote it for my SGI f77 compiler, but I wrote it in the most transportable fashion I know how.

All (I hope) compiler-specific code is in the sys_sgi.f or sys_pcl.f files.  You may need to make some changes to one of those files to get it to work with another compiler.  Many (if not all) of the routines found there are the same as those used for GPP.  You can download a copy of the GPP UNIX source code to get versions of these routines for other UNIX compilers.  Check out the sys_*.f files for system-specific routines for other compilers.

You may download the following files from our server:

• Change Log (v2.01, 04-Oct-1996, 0.3KB)

  This is the Trans change log.  Look at this text file to see if we've made worthwhile changes since you received your previous version of GPP.

• trans_201.tar.Z (v2.01, 11-Apr-1997, 11.1KB)

  This is the compressed archive of version 2.01 of Trans for UNIX.  It contains the source code for Trans with system routines for SGI, Sun, and HP UNIX compilers.  It also includes a makefile.

  After downloading this file, enter the following commands:

  uncompress trans_201.tar.Z
  tar xvf trans_201.tar

  To compile the program, modify the makefile (if necessary) and enter make.

• trns201e.exe (v2.01, 04-Oct-1996, 142.3KB)

  This is the self-extracting PC archive of version 2.01 of Trans. It contains a DOS executable. I compiled it with Lahey's LF90™ version 2.01i compiler.

• trns201s.exe (v2.01, 04-Oct-1996, 8.1KB)

  This is the self-extracting PC archive of version 2.01 of Trans.  It contains the Trans source code for the Lahey LF90™ compiler and make files.

If you want to refer to the Trans website in a report, here is a reference you can use:

NWTC Design Codes (Trans by Marshall Buhl).  http://wind.nrel.gov/designcodes/preprocessors/trans/.  Last modified 05-October-2004; accessed 05-October-2004.