In OpenSim 3.1, we've focused on improving the OpenSim scripting interface, accessible through the Graphical User Interface (GUI) and Matlab. We've also added to the OpenSim modeling and simulation libraries, with new components for modeling devices and estimating metabolic cost. OpenSim 3.1 also includes several usability improvements, including a toolbar for quickly running a forward simulation. As with every release, we've also implemented performance improvements and bug fixes. Improvements and additions include:

Enhanced scripting interface in Matlab and the GUI

Scripting through Matlab and the GUI allows users to call the full set of OpenSim modeling and simulation libraries (the API) without learning C++. Scripting also allows users to create batch scripts to streamline their workflows. We  improved the OpenSim scripting interface for OpenSim 3.1. Enhancements include:

Metabolic calculators

The metabolic calculators or probes, based on the work of Umberger and colleagues (2010) and Bhargava and colleagues (2004), estimate cost during motion for the whole body or individual muscles. Learn more about OpenSim Probes in the User's Guide and try them out in the example Simulation-Based Design to Reduce Metabolic Cost.

Expanded modeling toolbox

The toolbox is designed to improve OpenSim's ability to design assistive devices and other mechanisms. The new components can interface with the OpenSim workflow (e.g. computed muscle control) and are editable in the GUI. Where appropriate, they are visualized in the GUI and the API visualizer. The new components include:

You can find documentation for each of these components in the OpenSim Doxygen, look up how to define these components in the GUI's XML Browser, and see examples in the new tutorial Dynamic Walking Challenge: Go the Distance!.

Forward simulation toolbar in the GUI

The new toolbar for quickly running forward simulations in the GUI allows users to:

Performance and accuracy improvements

Additional Usability Improvements

Additional API Improvements

New examples

We've added to the library of OpenSim examples and tutorials. New materials include:

Bug fixes