I am currently using a mocap model to simulate walking trials.
As a first step I run the RunParameterIdentification operation. Regarding this, I specify with the following lines of code the trial from which segment scaling and marker parameters are loaded from (i.e, an upright standing static trial).
LoadParametersFrom ={"Static upright standing"};
When I only run the RunParameterIdentification, why do I see the model waliking? Shouldn't it just stand upright as specified above?
The process RunParameterIdentification will run the parameter optimization study on the current trial and save the outputs in a text file.
When you specify the variable LoadParametersFrom, it specifies which file will be used for loading the parameters. There is another operation for loading parameters in the RunAnalysis operation sequence.
So, you should normally run RunParameterIdentification on your standing trial and then, for the other trials, you should run the RunAnalysis operation that will load the parameters from the trial you specify in LoadParametersFrom and then run marker tracking and inverse dynamics analysis on the current trial file.
Thank you very much for your reply!
I'm now running RunParameterIdentification of a standing trial, however after 1 hour only 14/100 steps of ParameterOptimization are completed. Do you have any suggestions to speed it up?
One of the first things I would suggest is to cut down the number of frames of your standing trial. You can do that through the TrialSpecificData.any by specifying the First and Last frame.
Next, I suppose you can look into the marker protocol and see if you can adjust the marker positions to match them a little bit better to the marker positions from the trial. One other thing that you should look into is if you are optimizing marker position in directions that are also being optimized in another way, for e.g, you are optimizing the vertical position of the marker on the knee and the segment lengths of thigh and shank. This will make it harder for the solver to find the right solution.
Besides these solutions, I would also suggest you to restart AnyBody if you have been using it for a long time (there is an annoying bug that make the solver slow if you keep using it for a long time). Try to switch off the model view update.