Hi, I am attaching a script and some utility functions that I use in Python. Please note that some settings (rotation, mirror) should be changed to correspond to your lab's coordinate system. scripts.zip Hi @Dimitar, I've set up python 3.7 and OpenSim 4.1 in my Anaconda-Spyder environment. When I t...

To anyone wondering, this has issue has been resolved. Along with the Rajagopal model download, it comes with a Geometry folder that you need to direct the OS GUI to instead of the default folder.

Hello, I've been working with the Rajagopal model and it appears as if the femoral head is dislocated from the acetabulum (see attached *_original image). When taking the location in parent from other OpenSim models that use the Delp model as a base such as Gait1018, the hip appears to be in the cor...

Hello, I am using a modified Rajagopal model that replaced the Walker knee with a 6 dof customized joint. I ran CMC on the RRA results and found that certain muscles were not being activated during a landing task. I then ran a muscle analysis and discovered that these muscles were not lengthening or...

Hi Nicos, I had this same problem, which was solved by doing the following: -Make RRA_OPT_GUI_R1 your cd in matlab -Add Matlab_Code_GUI folder and subfolders to your path -Copy over all of the following files associated with the model/trial you are trying to optimize to the RRA_OPT_GUI_R1 folder: gr...

Hi Chris,

Thank you for the information. Yes, the issue was the ligaments as they were too stiff so the SO was failing to find a solution at various time points, which resulted in the large spikes. Muscle forces are smooth when the ligaments are loosened up.

Thanks everyone for your help!

-Kenneth

Hi Everyone, I’m applying patient-specific knee joints to the Rajagopal model based on MRI data. Therefore, I am able to discern the ligament origins and insertions as well as CSA but I am unsure how to go about determining their resting lengths. I.e. I do not know at what length these ligaments go ...

Hi Nicos, Yes, I had issues when there were no GRF present to account for the movement/accelerations of the bodies in space. These left very large "hand of God" residual forces at the pelvis but through the RRA optimizer I provided a link to, they were reduced down below the recommendations. I reall...

Hi Nicos, I've also gone through RRA and had issues with the residuals being very high. I was looking at jump landing and my residuals were high prior to landing (i.e. any GRF being read by the force plates). How do your rotational and translational errors look? Do they also satisfy the suggestions ...

Thanks everyone for your suggestions. James - These are direct outputs of SO. Although I have run a muscle analysis, I am still rather unsure on how to effectively use the outputs. As this is one of my goals this week is to develop a better understanding of muscle analysis, do you have any literatur...