Output Descriptions


Where can I find descriptions to all the outputs for the Mocap MarkerTracking and InverseDyanmicStudies?

For instance - in MarkerTracking, under ModelEnvironmentConnections, for each marker driver there are several outputs (TrajectoryPos, MarkerRef>r, etc). Are there descriptions somewhere of what each of there are?



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Hi @asylves4

There is not a formal description of all outputs since they can vary across studies and are model specific.

The MarkerRef.r you are mentioning is the global positions vector of the MarkerRef object.
In general the .r is global position, .rDot is the velocity and .rDDot is the acceleration.
To find the description of a specific output you can use the reference manual. Look under Help -> Reference Manual in the toolbar. There you can look up all classes and see they output variables with descriptions and type annotations.

Best regards,


Thanks for the response. One output specifically that I am looking into is using the Schreiber and Moissenent 2019 data with the ADL model. The output from marker tracking that is called TrajectoryPos, which is located in the Model Environment Connection folder. I had interpreted these as the position of the markers from the c3d file. The numeric values are different from those directly read from the c3d, but notes in the model state that marker filtering is turned off. Have I misunderstood "TrajectoryPos" in the model output? Or is it possible some default filtering is still occurring?


Hi Adam

I couldn't see anything called "TrajectoryPos" in the model. Maybe I am using a different version. What is the full name of you are looking at?

Hi @Bjorn,
I am also looking for the description for output, and I can find some definitions for muscles in:

While I can't find any info for joints. Could you please tell me how to identify a path is a joint and the basic attributes like rotation degree? Thanks!

Hi @querye,

As Bjørn has mentioned, the best way to learn is to check the ref. manual to see what class members can be used (F1 button on class name). But generally speaking each kinematic measure and joint class has a Pos member, which contains measured value(s). Pos for rotational degrees of freedom is measured in radians, but you can construct a necessary variable converting it into degrees (..[pathhere].Pos*180/pi).

Kind regards,