plot after apply external force to model

[saeed aram]

hello
I added an external force on tibia_r body to gait2354 model of opensim. then applied a motion (subject01_walk1_states_degree.mot) to that model. after I plotted a diagram of knee_angle_r to time for model before and after of added external force but i didnt see any change in diagram. I want to know why doesnt it change?

[Thomas Uchida]

I added an external force on tibia_r body to gait2354 model of opensim. then applied a motion (subject01_walk1_states_degree.mot) to that model. after I plotted a diagram of knee_angle_r to time for model before and after of added external force but i didnt see any change in diagram. I want to know why doesnt it change?

The knee angle will not change if you are forcing the model to track the same motion as before.

[saeed aram]

I added an external force on tibia_r body to gait2354 model of opensim. then applied a motion (subject01_walk1_states_degree.mot) to that model. after I plotted a diagram of knee_angle_r to time for model before and after of added external force but i didnt see any change in diagram. I want to know why doesnt it change?

The knee angle will not change if you are forcing the model to track the same motion as before.

thanks for your response
so what should I do if I want to plot model after applying external force to the tibia ( how can I set new motion with this external force to model )?

[Thomas Uchida]

so what should I do if I want to plot model after applying external force to the tibia ( how can I set new motion with this external force to model )?

Please see the "The Forward Problem" section of the "Overview of the OpenSim Workflow" page in the Confluence documentation (https://simtk-confluence.stanford.edu:8 ... m+Workflow). Some recent work in this area is described in Ong et al. (2019) Predicting gait adaptations due to ankle plantarflexor muscle weakness and contracture using physics-based musculoskeletal simulations, https://doi.org/10.1101/597294.