View Full Version : Locomotion Analysis Software Available

unknown user
09-21-1992, 01:54 AM
This is a brief description of a locomotion analysis package that I have
developed over the past several years. Hope someone will find it useful.

-dwight meglan

Software for the Analysis and Display of Human Locomotion

The Anz/Telio/Show3d package is a set of computer programs for use in the
research as well as the clinical evaluation of human locomotion. Together,
these allow the analysis, plotting, and graphical display in 3 dimensions
of body segment kinematics and kinetics. The software, developed for VAX/VMS
in FORTRAN at The Ohio State University Gait Analysis Lab, is being made
available in source code and executable form to facilitate researchers and
clinicians in the development of their own locomotion analysis software.


Anz uses measured marker trajectories to produce estimates of spatial limb
kinematics, absolute and relative, including translational and rotational
velocities and accelerations. These can be combined with force plate data
to evaluate net joint resultant loads and joint power transfers. The
majority of the analysis methods are based upon segmental local coordinate
systems that are marker system independent. Several marker sets are currently
supported. Many general kinematics and kinetics procedures are included as
well as a number of gait specific evaluations. In a number of evaluations,
several methods are provided to do the same calculation. Muscle EMG data may
also be processed with digital filtering. The program is command line based
and can be operated interactively for exploratory analysis or, when
running under VMS, can be used repeatedly via command files to yield a product-
ion environment for clinical gait evaluation. The results of an analysis are
stored in a single binary format file constructed to be transportable
between different computers. The contents of this file can be examined with
Telio to produce graphs, Show3d to produce 3D figures, or exported from Anz in
text format for further processing. The commands used to produce the
analysis results are stored in the Anz binary file providing a history of the
calculation process.


Telio is a command line driven program to graphically display the results
of Anz analyses. It can also read several data file formats native to the
VICON marker tracking system. The program has a flexible display format so
that screen displays and/or printouts can be produced using either time
series or crossplotting of data. Data may be read from multiple files and a
number of graphs generated at one time. A macro facility has been included to
simplify generating complex displays. Combined with a command file in VMS,
printouts of data can be produced without any user interaction. Thus, the
program functions as both an exploratory and a production display tool. A
number of gait specific features are included to produce clinically useful
gait displays. The DI3000 graphics subroutine library from Precision Visuals
Inc. is used to provide device independent graphics capabilities. This
package must be installed to use Telio. The source code must be modified if
another graphics package is used.


Show3d generates 3D views of marker trajectories and body segments as
analyzed by Anz to allow visualization of motion from any direction. Body
segments are represented by parallelapipeds to emphasize nonsagittal plane
motions. Segments may be represented with hidden lines removed. A number of
customization options are available including the display of the images on
screen and/or via printed form. This program also uses the DI3000 graphics
package. A recent addition to Show3d is that the ground reaction forces can
be superimposed on the segment display or displayed separately.


The source code uses VAX extensions to FORTRAN but no system specific
routines, so any FORTRAN compiler supporting VAX extensions can be used.
Presently, the software supports VICON and AMASS video and analog data files.
Support for Motion Analysis Corporation marker and analog data files has
been added recently.

The source code is rather large, totaling more than 1.5 MBytes. The software
is copyrighted and has been placed in the public domain as a research and
instructional tool only and as such is UNSUPPORTED. The source code may be
freely modified and redistributed for nonprofit purposes as long as the
changes are clearly marked and the origin of the software, The Ohio State
University Gait Analysis Laboratory, is mentioned.


Source code only of these programs is available in UNIX, PC, and Macintosh
archive formats while source code as well as executables and sample data are
available for VAX/VMS in compressed, backup format files. The UNIX, PC, and Mac
archives are available via anonymous FTP from two sites:

ftp.nici.kun.nl in directory pub/biomch-l
magnus.acs.ohio-state.edu in directory pub/gaitlab

The VAX/VMS backup files are only available from magnus.acs.ohio-state.edu
A readme.txt file at each site provides details about obtaining and dearchiving
the files. Several text files describing the commands in ANZ and TELIO as well
as a detailed overview of ANZ's calculation capabilities are also available at
the archive sites.

Copies of hand written notes of the derivations of the kinematics and kinetics
algorithms within ANZ (~50 pages) are availabe from the program author for $10
US (to cover duplication and shipping). If FTP access is not available, the PC
or Macintosh archives with derivation notes can be obtained from the author for
$20 US. The VAX/VMS files can be ordered on 1/2" tape only for $30 US.

All requests for derivation notes or copies of the software should be sent
prepaid in US currency to:

Dwight Meglan
Orthopaedic Biomechanics Laboratory
The Mayo Clinic
128 Guggenheim
Rochester, MN 55906 USA