OpenSim 3.3 or 3.2 and Scale Tool
Posted: Mon Apr 23, 2018 5:56 pm
Hello all,
We are using an OpenSim model to investigate the effects of single-leg landings, and have some questions related to the 1st steps using OpenSim.
1) We start using OpenSim 3.3, but we rolled back to version 3.2, because we were not able to see the virtual and experimental marker sets once we applied the Scale Tool. We cannot identify where the error is shown or where to make any adjustments to the marker set if needed (v3.3). However, we would like to see and identify the errors, and understand how to appropriately adjust them in version 3.3. Could you provide a brief explanation where we can identify the error of the markers and how to adjust them (v3.3), as we did not find any documentation on this matter, please?
2) At which point in the process should we provide a weight to the marker: at scale tool or inverse kinematics tool? We know that we should weight them to give more "relevance" to some markers, but this step is not explicit in the OpenSim documentation.
3) After scaling the model (Scale Tool), what is the error (max and RMS) that we should be looking at, between 2 and 4 cm (max) and 2 cm (RMS)?
4) Where can we find more information concerning the muscles that have more than one part? For example, the gluteus medius (glu-med1, glu-med2, glut-med3). We speculate that it is related with muscles action, but can you guide us to documentation (e.g., OpenSim website, manuscripts, etc.) regarding this topic?
5) While the tutorials are extremely useful, some of them do not entirely match with the current version (v3.3). Do you have an update planned for the tutorials (i.e., the scaling tool and IK)?
Thank you for your time and consideration,
Ana Azevedo
We are using an OpenSim model to investigate the effects of single-leg landings, and have some questions related to the 1st steps using OpenSim.
1) We start using OpenSim 3.3, but we rolled back to version 3.2, because we were not able to see the virtual and experimental marker sets once we applied the Scale Tool. We cannot identify where the error is shown or where to make any adjustments to the marker set if needed (v3.3). However, we would like to see and identify the errors, and understand how to appropriately adjust them in version 3.3. Could you provide a brief explanation where we can identify the error of the markers and how to adjust them (v3.3), as we did not find any documentation on this matter, please?
2) At which point in the process should we provide a weight to the marker: at scale tool or inverse kinematics tool? We know that we should weight them to give more "relevance" to some markers, but this step is not explicit in the OpenSim documentation.
3) After scaling the model (Scale Tool), what is the error (max and RMS) that we should be looking at, between 2 and 4 cm (max) and 2 cm (RMS)?
4) Where can we find more information concerning the muscles that have more than one part? For example, the gluteus medius (glu-med1, glu-med2, glut-med3). We speculate that it is related with muscles action, but can you guide us to documentation (e.g., OpenSim website, manuscripts, etc.) regarding this topic?
5) While the tutorials are extremely useful, some of them do not entirely match with the current version (v3.3). Do you have an update planned for the tutorials (i.e., the scaling tool and IK)?
Thank you for your time and consideration,
Ana Azevedo