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Hello, I'm encountering an issue with RRA. After running the RRA tool on my model, I manually adjusted the recommended mass change suggested by OpenSim in an attempt to minimize the residuals. According to the documentation, I should aim for a maximum residual force of 25 N. However, the messages in OpenSim only display average residuals (e.g., FX=0.244415 FY=3.05569 FZ=6.03278, MX=3.84448 MY=-13.569 MZ=3.58083). I tried to open the rra_Actuation_force.sto file, but the forces appear to be unreasonable, with a maximum value of 9640.273 N. How can I address this issue and reduce the residuals? Also, are the values in the rra_Actuation_force.sto file the residuals?

Which residual is reaching < 9000N? In the screenshot there are some large FY values (>200 N). This might point out that there is an issue with the external forces you are applying to the model (either in magnitude or location or both). One way to check is to run Inverse Dynamics and see if reasonable results come out first, before using RRA, to check if your data is in good shape.