Hallo everybody,
I tried to calculate the derivative of some angular coordinates. I compared the result with the angular velocities from the Analyse Tool. Both calculations match very good.
After that I tried to calculate the second derivative and it seems that the result of the Analyse Tool is wrong. I checked the calculations also with the data from the Gait2354_Simbody model. Every accaleration value is negative this must be wrong. Did anyone else recognize this?
Another question, the derivatives depend on the filter cut off frequenzy. Does anyone know wich filter is used and how the derivative is implemented?
Best regards
Nils