GaitSym 2014

GaitSym is a forward dynamic modelling program. What that means is that you specify the forces and the program uses Newton's Laws to calculate the movements. It uses the Open Dynamics Engine physics library to do most of the hard work ( and provides a file format and display system so the user does not have to do any programming. It also provides various muscle models so that the forces can be generated directly from muscle activation levels and a number of hooks to allow it to be used with global optimisation tools such as genetic algorithms. The software is open source and is released under the GNU General Public License version 3.0 except for parts of the software that are covered by different licences (for example the OpenDE portions are covered by either Lesser GPL or a BSD license). If this license does not let you do what you want to do then please contact me and I am sure I can sort something out.

GaitSym 2014 with a human model.


The following downloads are provided:
You can also browse the GaitSym 2014 source code.


The program is developed under MacOSX Yosemite using the Qt 5.3 GNU GPL v. 3.0 Version cross-platform development system. It therefore compiles and runs on many of the Qt supported platforms including Linux and Windows. There is also a command line version designed for batch processing. Source code, makefiles and Qt project files are provided for MacOSX, Linux and for MinGW to allow compilation under Windows. Binary files for MacOSX and Windows are also provided.
  • For MacOSX, double-click the downloaded DMG file and drag the application to a convenient place on your hard drive.
  • For Windows, double click the downloaded ZIP file and decompress the contents to a convenient folder on your hard drive. The EXE file has been compiled statically under Windows 7 so should run anywhere with no dependencies but let me know if there are problems.
  • For Linux you will need to compile the source code and also the dependencies provided.

What's New

  • Brand new look that should run much better on a variety of different screen sizes.
  • New on screen indicators for kinematic matching.
  • New from Geometry command: create a new model from a folder of .OBJ files.
  • Relative models are saved in posable format if possible.
  • Some small config file changes so you should use the reference guide in the GaitSym 2014 manual.
  • Plenty of bug fixes.

All old models should still load but simulation changes may mean that there are numerical differences in the calculated outputs.