- opensim-moco-announce - SimTK Mailing Lists

Webinar on muscle-driven simulations of cycling using OpenSim Moco
by Nick Bianco 12 Apr '24

12 Apr '24

Hi Moco users, I wanted to inform you of an upcoming webinar by Caitlin Clancy from Stanford University featuring cycling simulations in OpenSim Moco. While the webinar is geared towards cycling, the tips and best practices shared are useful for many other applications using Moco, so I encourage you to check it out! More details are below. Best, Nick *Webinar on Muscle-Driven Simulations and Experimental Data for Cycling*We are pleased to announce our upcoming webinar with Caitlin Clancy from Stanford University entitled “Muscle-Driven Simulations and Experimental Data of Cycling.” She will discuss her team’s approach to generating simulations of cycling using OpenSim Moco <https://opensim-org.github.io/opensim-moco-site/>, and share best practices for iterating and refining her Moco optimization problem. This event will be hosted jointly by the Restore and Mobilize Center on Wednesday, April 17, 2024, at 9:00 AM Pacific Time. Learn more and register <https://mobilize.stanford.edu/webinar-musculoskeletal-simulations-and-exper…> | Read the paper <https://doi.org/10.1038/s41598-023-47945-5> -- *Nicholas Bianco, PhD* Research Engineer Wu Tsai Human Performance Alliance <https://humanperformance.stanford.edu/> Stanford University | NMBL <https://nmbl.stanford.edu/people/nick-bianco/>

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New Moco features available in OpenSim 4.5
by Nick Bianco 07 Mar '24

07 Mar '24

Hello Moco users! I'm excited to announce a set of new Moco features included in the recent OpenSim 4.5 release. This release includes a new class for modeling muscle paths with polynomial functions, new options for configuring MocoGoals, new transcription schemes, updated examples, and plenty of bug fixes. Learn more about these new features in the Release 1.3.0 blog post <https://opensim-org.github.io/opensim-moco-site/blog/> on the Moco website. Best, Nick -- *Nicholas Bianco, PhD* Research Engineer Wu Tsai Human Performance Alliance <https://humanperformance.stanford.edu/> Stanford University | NMBL <https://nmbl.stanford.edu/people/nick-bianco/>

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Fwd: [Opensim-announcement] Virtual Office Hours, NSF-DARE Conference
by Nick Bianco 12 Jan '23

12 Jan '23

Hello Moco users, You may have seen the recent OpenSim announcement below about our next set of Virtual Office Hours coming up at the end of the month. Please feel free to apply with any Moco-related questions you have in addition to the other topics listed below. The deadline is tomorrow, January 13, 5pm. Best, Nick ---------- Forwarded message --------- From: Matthew Petrucci <mpetrucc(a)stanford.edu> Date: Wed, Jan 11, 2023 at 11:45 AM Subject: [Opensim-announcement] Virtual Office Hours, NSF-DARE Conference To: opensim-announcement(a)simtk.org <opensim-announcement(a)simtk.org> *Apply to Participate in Virtual Office Hours for Biomechanical Modeling or Machine Learning Research Questions * *Application Deadline: January 13, 2023, 5 PM local time * *Office Hour Dates: January 30-February 3, 2023 * We are pleased to announce we will be holding Virtual Office Hours January 30-February 3, 2023 to support researchers working with wearable sensors, video technology, and other modalities in rehabilitation research. We will have three tracks: 1) OpenCap <http://opencap.ai/> or other video-based analysis of movement 2) OpenSim <https://opensim.stanford.edu/> or other questions about biomechanical modeling, including via IMUs and 3) Machine learning with time series or other movement/rehab data. All phases of a research project are supported, such as formulating a research question, choosing and planning appropriate methods, and addressing issues with carrying out the study. We welcome and encourage individuals to apply as a team, if relevant. Learn more and apply <https://restore.stanford.edu/2022/11/30/apply-to-participate-in-virtual-off…> *Participate in NSF-DARE Conference on Modeling in Neurorehabilitation* *Abstract Deadline: January 15, 2023, 11:59 PM PST* *Conference Dates: March 3-4, 2023* The University of Southern California (USC) and the University of Washington are hosting a conference entitled "Transformative Opportunities for Modeling in Neurorehabilitation" at USC on March 3-4, 2023. This conference is supported by the NSF-DARE <https://beta.nsf.gov/funding/opportunities/disability-rehabilitation-engine…> and will bring together experts and trainees from around the world to discuss critical questions, challenges, and opportunities at the intersection of computational modeling and neurorehabilitation. They will focus on four areas of impact: 1) modeling adaptation and plasticity, 2) modeling for personalization, 3) modeling human-device interactions, and 4) modeling in the wild. Learn more and register <https://dare2023.usc.edu/> | Submit abstract <https://sites.usc.edu/dare2023/abstract-submission/> _______________________________________________ Opensim-announcement mailing list Opensim-announcement(a)simtk.org https://simtk.org/mailman/listinfo/opensim-announcement

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Release: Moco version 1.2.0
by Nick Bianco 31 Oct '22

31 Oct '22

Hello Moco users, I've been receiving lots of questions about MocoOutputGoal on the Moco forum recently, which made me realize that I never sent out an announcement for the latest Moco updates! OpenSim 4.4 with Moco 1.2.0 was released this past summer, and it includes some useful updates to MocoOutputGoal along with some other additions and bug fixes. In OpenSim, Output <https://simtk.org/api_docs/opensim/api_docs44/classOpenSim_1_1Output.htm>s allow you to query values from a Model that are calculated from a State object. We created MocoOutputGoal to make it easier to build custom cost functions in Moco that depend on Output values. In Moco 1.2.0, we've updated MocoOutputGoal to now support not only scalar Output types, but also Vec3 and SpatialVec types, which covers the majority of Outputs offered by OpenSim Components. We've also added new MocoGoals which allow you to minimize an Output at the beginning of a trajectory (MocoInitialOutputGoal), an Output at the end of a trajectory (MocoFinalOutputGoal), the error between initial and final Output values (MocoOutputPeriodicityGoal), and the error between an Output and a user-provided trajectory (MocoOutputTrackingGoal). In addition, we added MocoOutputConstraint to allow you to include Output values in a path constraint in your problems. Many users have requested more flexibility in building cost functions in Moco, and these new Output-based goals will give you many more options to do so. Other updates include fixes for MocoAngularVelocityTrackingGoal and MocoOrientationTrackingGoal, which were not properly supported in Matlab and Python. We fixed a bug that was breaking marker tracking problems when using 'setMarkersReferenceFromTRC()' in MocoTrack. We fixed a bug where calculations from MocoStudy's 'analyze()' were incorrect because DeGrooteFregly2016Muscle auxiliary variables were not properly included. Finally, we implemented a fix for DeGrooteFregly2016Muscle so that optimal fiber lengths and tendon slack lengths are scaled when using the ScaleTool. Get Moco 1.2.0 by downloading the OpenSim 4.4 release from SimTK <https://simtk.org/frs/?group_id=91>. More details about this release can be found in the CHANGELOG <https://github.com/opensim-org/opensim-core/blob/master/CHANGELOG.md> and CHANGELOG_MOCO <https://github.com/opensim-org/opensim-core/blob/master/CHANGELOG_MOCO.md> files. Read the Moco paper here <https://journals.plos.org/ploscompbiol/article?id=10.1371/journal.pcbi.1008…> . -Nick -- *Nicholas A. Bianco* Neuromuscular Biomechanics Lab <http://nmbl.stanford.edu/people/nick-bianco/>|Stanford PhD Candidate (772) 284-0354

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Release: Moco version 1.1.0
by Nick Bianco 13 Oct '21

13 Oct '21

Hello Moco users, OpenSim 4.3 was officially released a few weeks ago, and included is the latest Moco release, version 1.1.0. This release includes a variety of new examples and new features to help you answer a broader set of research questions. The examples exampleIMUTracking <https://github.com/opensim-org/opensim-core/tree/master/Bindings/Java/Matla…> and exampleEMGTracking <https://github.com/opensim-org/opensim-core/tree/master/Bindings/Java/Matla…> were added for the recent 2021 meeting of the Technical Group on Computer Simulation (TGCS). The first example demonstrates how to create a set of synthetic accelerometer signals from a squat-to-stand motion, and then track these signals to reconstruct the original trajectory; this example is a great starting point for incorporating signals from inertial measurement units in your simulations. The second example demonstrates how to solve the muscle redundancy problem using MocoInverse while tracking electromyography signals. This example includes a new feature that allows you to optimize scale factors that allow you to track the shape of the reference EMG signals while scaling their magnitudes. Two user-contributed examples that expand the popular example2DWalking are featured in this release. A Matlab version of example2DWalkingMetabolics <https://github.com/opensim-org/opensim-core/blob/master/Bindings/Java/Matla…>, contributed by Brian Umberger, has been included to make it easier to get started minimizing metabolic cost in a predictive simulation. Russell Johnson contributed example2DWalkingStepAsymmetry <https://github.com/opensim-org/opensim-core/blob/master/Bindings/Java/Matla…> which demonstrates how to predict an asymmetric walking pattern with Moco. This example features the new goals MocoStepTimeAsymmetryGoal and MocoStepLengthAsymmetryGoal which allow you to target specified step time asymmetry and step length asymmetry values with terms in the cost function. Get Moco 1.1.0 by downloading the OpenSim 4.3 release from SimTK <https://simtk.org/frs/?group_id=91>. More details about this release are in the CHANGELOG <https://github.com/opensim-org/opensim-core/blob/master/CHANGELOG.md> and CHANGELOG_MOCO <https://github.com/opensim-org/opensim-core/blob/master/CHANGELOG_MOCO.md> files. Read the Moco paper here <https://journals.plos.org/ploscompbiol/article?id=10.1371/journal.pcbi.1008…>. -Nick -- *Nicholas A. Bianco* Neuromuscular Biomechanics Lab <http://nmbl.stanford.edu/people/nick-bianco/>|Stanford PhD Candidate (772) 284-0354

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Moco 1.0.0 Release
by Nick Bianco 08 Apr '21

08 Apr '21

Hello Moco Users, Per the recent announcement from Jen Hicks, the newest version of Moco has been released along with OpenSim 4.2! Since Moco is now merged into the core OpenSim codebase, we’re calling this release Moco 1.0.0. It’s been a long wait since the last release, but the time spent unifying the Moco and OpenSim codes will ensure long term stability for the Moco project and will allow for faster development cycles going forward. Thanks to those who have been active contributors to the Moco forum <https://simtk.org/plugins/phpBB/indexPhpbb.php?group_id=1815&pluginname=php…>! Even though Moco releases will now be included with OpenSim releases on the main OpenSim SimTK page, the Moco SimTK forum will remain the main hub for all Moco related discussion. In this release we’ve added the component Bhargava2004SmoothedMuscleMetabolics, a smoothed implementation of the Bhargava et al. (2004) metabolics model designed for gradient-based optimization (contributed by Antoine Falisse). With this component and MocoOutputGoal, you can now include metabolic cost terms in the objective function. We’ve fixed two major bugs related to muscle wrapping where 1) ModOpReplaceMusclesWithDeGrooteFregly2016 did not copy over the original muscle’s PathWrapSet and 2) muscle wrapping wasn’t thread-safe, which disallowed parallelization with MocoCasADiSolver. Muscle wrapping should now work seamlessly without needing to change how you construct your models with ModelProcessor. As always, various other small bugs fixes and changes are included with this release. Read about them on the blog post here <https://opensim-org.github.io/opensim-moco-site/blog/>. Finally, the Moco paper has been published in PLOS Computational Biology! Read the paper here <https://journals.plos.org/ploscompbiol/article?id=10.1371/journal.pcbi.1008…> . Get Moco 1.0.0 by downloading the OpenSim 4.2 release from SimTK <https://simtk.org/frs/?group_id=91>. Best, -Nick -- *Nicholas A. Bianco* Neuromuscular Biomechanics Lab <http://nmbl.stanford.edu/people/nick-bianco/>|Stanford PhD Candidate (772) 284-0354

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Muscle wrapping bugs with DeGrooteFregly2016Muscle
by Nick Bianco 30 Nov '20

30 Nov '20

Hello Moco users, We've recently found a few critical bugs regarding muscle wrapping with the DeGrooteFregly2016Muscle in Moco. These bugs include wrapping surfaces not being copied into DeGrooteFregly2016Muscles when using ModOpReplaceMusclesWithDeGrooteFregly2016 and wrapping surfaces not supporting parallelism in MocoCasADiSolver. Please refer to this SimTK forum post for full details: https://simtk.org/plugins/phpBB/viewtopicPhpbb.php?f=1815&t=12792&p=0&start… . We are working on fixes for these issues now, and they will be included in the next release of Moco (which will be included with the OpenSim 4.2 release). Best, -Nick -- *Nicholas A. Bianco* Neuromuscular Biomechanics Lab <http://nmbl.stanford.edu/people/nick-bianco/>|Stanford PhD Candidate (772) 284-0354

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Ross Miller shares walking simulations using Moco
by Christopher L. Dembia 16 Apr '20

16 Apr '20

Ross Miller has created a SimTK project to share his work using Moco: https://simtk.org/projects/umocod. If you’re hoping to get a jump start with Moco, I encourage you to visit his project. We love when users share their progress with the Moco team and make their work available. Thank you, Ross! Here is a description of the project by Ross Miller: The model is designed for optimal control simulations of general musculoskeletal motion and walking specifically. The main differences from Moco’s 2D walking example include tendon compliance in all muscles, a two-segment foot, a patella with kinematic constraints, tracking of human experimental kinematic and ground reaction force data, and simulation of a full stride. A solution to a MocoTrack problem with the model is included and would serve as a good initial guess to predictive simulations. The long-term goal of the project is predictive simulations of muscle strengthening and prosthesis parameter optimization after lower limb loss. The project is a collaboration with Dr. Elizabeth Russell Esposito at the Seattle VA and is funded by the Army Advanced medical Technology Initiative and the Henry M. Jackson Foundation.

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Release 0.3.0
by Nick Bianco 23 Jan '20

23 Jan '20

We're happy to announce the latest release of Moco, version 0.3.0. This release adds contact force tracking via the MocoContactTrackingGoal class and new methods to MocoSolution that provide values of individual terms in the objective function. Other minor changes in this release include renaming exampleSitToStand to exampleSquatToStand, moving the bisection root solver in DeGrooteFregly2016Muscle to a dedicated utility in MocoUtilities, and a bug fix in the Python report generation tool. See the blog post about this release for more information: https://opensim-org.github.io/opensim-moco-site/blog/2020/01/23/release-0.3… . Cheers, The Moco team

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Release 0.2.0
by Christopher Dembia 18 Dec '19

18 Dec '19

We are glad to announce the second release of Moco, version 0.2.0. This release contains a MATLAB version of Moco’s 2D predictive simulation of walking, contributed by Brian Umberger, and examples in MATLAB, Python, and C++ for using the MocoInverse tool. Lastly, we added examples for creating a custom goal in C++; see exampleSlidingMassAdvanced.cpp and exampleMocoCustomEffortGoal. To easily plot a solution in MATLAB, we introduced the osimMocoTrajectoryReport.m utility. We updated the versions of Simbody and OpenSim that we bundle with Moco. As a result, this release contains a fix for the simbody-visualizer for macOS Catalina, and contains OpenSim’s support for IMUs. See the blog post about this release for more information: https://opensim-org.github.io/opensim-moco-site/blog/2019/12/17/release-0.2… <https://opensim-org.github.io/opensim-moco-site/blog/2019/12/17/release-0.2…> Happy holidays, The Moco team

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