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Provide easy-to-use, extensible software for modeling, simulating, controlling, and analyzing the neuromusculoskeletal system.

License: Github Source Code Repository, OpenSim, OpenSim Models and Examples, OpenSim Source Code

OpenSim is a freely available, user extensible software system that lets users develop models of musculoskeletal structures and create dynamic simulations of movement.

Find out how to join the community and see the work being performed using OpenSim at

Access all of our OpenSim resources at the new
Support Site.

Watch our Introductory Video get an overview of the OpenSim project and see how modeling can be used to help plan surgery for children with cerebral palsy.


Webinar on Enabling Stochastic Simulations of Movement with High Throughput Computing

Nov 9, 2016

We invite you to join us for a webinar featuring Colin Smith and Darryl Thelen from the University of Wisconsin-Madison to learn how to run OpenSim simulations on the Open Science Grid and conduct probabilistic analyses to characterize your simulations.

OpenSim simulations yield insights into the design of assistive devices to reduce the metabolic cost of running

Oct 25, 2016

Mobilize Center researcher Thomas Uchida and OpenSim ( researchers published a paper in PLOS One where they generated muscle-driven simulations of movement to augment experimental data and provide insights into the design of assistive devices to reduce energy consumption during running.

Course on Open-Source Tools for Computational Biomechanics

Aug 30, 2016

The OpenSim team is participating in an IEEE Boston workshop on Thursday, September 15, 2016 that introduces participants to three open-source tools: GIBBON for image segmentation; FEBio for finite element analysis; and OpenSim for musculoskeletal modeling and simulation.

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The software provides a platform on which the biomechanics community can build a library of simulations that can be exchanged, tested, analyzed, and improved through multi-institutional collaboration. The underlying software is written in ANSI C++, and the graphical user interface (GUI) is written in Java.

OpenSim technology makes it possible to develop customized controllers, analyses, contact models, and muscle models among other things. These plugins can be shared without the need to alter or compile source code. Users can analyze existing models and simulations and develop new models and simulations from within the GUI.

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