Beta Testers - We need your help testing the next release of OpenSim - version 3.1. We'd appreciate feedback by the end of this week, if possible. Let us know what works and what needs improvement. https://simtk.org/project/xml/downloads.xml?group_id=91 *Scroll Down to "Release Betas"* I've included a list of new features and examples for you to try below. Please also try out the software with your usual workflows and note any bugs or issues with upgrading. Thanks in advance for your help! Jen *New Features in 3.1* 1) Metabolic calculators that estimate cost during motion for the whole body or individual muscles. See the new example<http://simtk-confluence.stanford.edu:8080/display/OpenSim/Simulation-Based+Design+to+Reduce+Metabolic+Cost> using metabolics. 2) Interactive simulation tools, including a run button for forward simulation and coord velocity 3) An expanded modeling toolbox for designing 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. The new components (plus links to doxygen) include: - A spring that acts along a path<https://simtk.org/api_docs/opensim/api_docs31/classOpenSim_1_1PathSpring.html> - A clutched path spring<https://simtk.org/api_docs/opensim/api_docs31/classOpenSim_1_1ClutchedPathSpring.html> - An expression based bushing<https://simtk.org/api_docs/opensim/api_docs31/classOpenSim_1_1ExpressionBasedBushingForce.html>that applies torques as a symbolic function of deflections - An expression based point to point force<https://simtk.org/api_docs/opensim/api_docs31/classOpenSim_1_1ExpressionBasedPointToPointForce.html>that applies forces as a function of deflection and deflection speed - A planar joint<https://simtk.org/api_docs/opensim/api_docs31/classOpenSim_1_1PlanarJoint.html> You can see many of these in action in the new example on building a dynamic walker<http://simtk-confluence.stanford.edu:8080/pages/viewpage.action?pageId=5113821> . 4) An enhanced scripting interface<http://simtk-confluence.stanford.edu:8080/display/OpenSim/Scripting>in Matlab, Python, and the GUI. Improvements include: - Expanded instructions for Matlab setup<http://simtk-confluence.stanford.edu:8080/display/OpenSim/Configuring+Matlab+for+OpenSim> - Exposure of nearly all of the OpenSim API, including key Simbody dynamics objects and functions - Usability improvements (e.g. autocomplete in Matlab and shortcuts to find and run recent scripts) - Improved error handling and reporting - Expanded plotting capabilites (e.g. to plot Millard muscle curves and threshold values) - A 64-bit build of OpenSim libraries for 64-bit Matlab. You can see the interface in action in the new examples on building a dynamic walker<http://simtk-confluence.stanford.edu:8080/pages/viewpage.action?pageId=5113821>and metabolic cost.<http://simtk-confluence.stanford.edu:8080/display/OpenSim/Simulation-Based+Design+to+Reduce+Metabolic+Cost> 5) Performance improvements and fixes to memory leaks and bugs 6) Expanded GUI editing capabilities for path components (PathSpring, Ligament, etc.) to enable editing like with muscles 6) New examples, including: - Simulation based-design of assistive devices to reduce metabolic cost<http://simtk-confluence.stanford.edu:8080/display/OpenSim/Simulation-Based+Design+to+Reduce+Metabolic+Cost> - Building a dynamic walker<http://simtk-confluence.stanford.edu:8080/pages/viewpage.action?pageId=5113821> -- *Jennifer Hicks, Ph.D.* Associate Director | NCSRR<http://www.stanford.edu/group/opensim/about/index.html> R&D Manager | OpenSim <http://opensim.stanford.edu/> Stanford University 650-498-4403 | jenhicks@stanford.edu