Search found 87 matches
- Sat Jun 03, 2023 3:43 am
- Forum: OpenSim
- Topic: Should we believe the motion resulted from RRA?
- Replies: 1
- Views: 483
Should we believe the motion resulted from RRA?
Hi all, I am reviewing the tutorial of static optimization https://simtk-confluence.stanford.edu:8443/display/OpenSim/Working+with+Static+Optimization . In this tutorial, Study 2 compares the output muscle activations and residual forces from unfiltered, filtered, and RRA motions. The unfiltered mot...
- Tue Nov 01, 2022 8:27 am
- Forum: OpenSim
- Topic: Models overlap when multiple models are loaded
- Replies: 2
- Views: 483
Re: Models overlap when multiple models are loaded
Hi Thomas,
Thanks a lot, it works.
Simon
Thanks a lot, it works.
Simon
- Mon Oct 31, 2022 11:52 pm
- Forum: OpenSim
- Topic: Models overlap when multiple models are loaded
- Replies: 2
- Views: 483
Models overlap when multiple models are loaded
Hi everyone,
When I load models in OpenSim 4.4, the third and subsequent models will overlap with the first one. There is no such matter in the previous version. How to solve this?
Thanks,
Simon
When I load models in OpenSim 4.4, the third and subsequent models will overlap with the first one. There is no such matter in the previous version. How to solve this?
Thanks,
Simon
- Wed Apr 13, 2022 1:56 am
- Forum: OpenSim Moco
- Topic: Sudden postural change happened while tuning objective function weighting
- Replies: 7
- Views: 1555
Re: Sudden postural change happened while tuning objective function weighting
Hi all, For multi-objective optimization, can we observe the whole Pareto front in Moco? I wanna graphically explain the reason why J1 and J2 could not predict a continuous postural change during w1 and w2 vary. My thought is to show all the Pareto optimum solutions and objective function lines (w1*...
- Tue Apr 12, 2022 9:02 pm
- Forum: OpenSim
- Topic: Minimum Time Optimal Control Problem
- Replies: 2
- Views: 650
Re: Minimum Time Optimal Control Problem
Hi Nicos Haralabidis, I am going to solve similar optimal control problems with Matlab fmincon. Could you please show me how to include the OpenSim model's system dynamics into the problem? I tried to write equations of motion by myself and added them to fmincon, but I feel hard and troublesome to d...
- Sat Apr 09, 2022 7:48 am
- Forum: OpenSim Moco
- Topic: Sudden postural change happened while tuning objective function weighting
- Replies: 7
- Views: 1555
Re: Sudden postural change happened while tuning objective function weighting
Hi Chonghui, I set the solution as an initial guess of a new MocoStudy, and set the maximum numbers of iteration to be zero. The code is following: solver.set_optim_max_iterations(0); This method was proposed by Nick in a previous thread but I cannot find it out. It outputs the objective function va...
- Thu Apr 07, 2022 7:59 am
- Forum: OpenSim Moco
- Topic: How can I make torque-driven predictive simulations realistic?
- Replies: 16
- Views: 2766
Re: How can I make torque-driven predictive simulations realistic?
One of the differences of torque-driven models from muscle-driven models is that the torque limit is regarded as a constant, or we say static joint strength, instead of a real dynamic joint strength. To include muscle properties into torque-driven models, we can construct a dynamic joint strength mo...
- Wed Apr 06, 2022 11:04 pm
- Forum: OpenSim Moco
- Topic: Sudden postural change happened while tuning objective function weighting
- Replies: 7
- Views: 1555
Re: Sudden postural change happened while tuning objective function weighting
Thank you Ton and Ross :D . I understand that this is not a problem of my model/setup, then I just want to explore why the discontinuities exist in posture prediction. According to the advice of Ton, I drew the resulting J1 and J2 in Figure(a). Also, I plotted some representative lines of w1*J1+w2*J...
- Tue Apr 05, 2022 8:23 am
- Forum: OpenSim Moco
- Topic: Sudden postural change happened while tuning objective function weighting
- Replies: 7
- Views: 1555
Sudden postural change happened while tuning objective function weighting
Hi all, I selected two goals to predict the initial posture of the box lifting motion in Moco. I'm sorry that I have to keep these goals a secret, because they are key innovations in my unpublished paper. Here I just nominate them as J1 and J2. When I minimize J1, I could get a squatting posture as ...
- Thu Mar 31, 2022 10:55 pm
- Forum: OpenSim
- Topic: How to constraint the lumbopelvic coordination?
- Replies: 0
- Views: 270
How to constraint the lumbopelvic coordination?
Hi all, I expect that my skeletal model could include the lumbopelvic coordination. As the attached figures show, the orientation of the torso is T, the orientation of the sacrum is beta, the knee angle is K. The coordination expression is : beta = -17.5 - 0.12T + 0.23K + 0.0012TK + 0.5T^2 - 0.00075...