Simscape PS converter error

Good morning,

I am trying to understand the difference between first and second order filtering concerning the block PS converter. I send a step input to the joint, but if I impose the first order filter it gives me an error (as shown in the attached file). I've tried to find some info about this block but and the details about filter, but I didn't find them. Could someone give me info about the filter and the differences? Why the first order doesn't work in my case?

Thanks in advance

Elisa

Answer 1

[J Chen]

The filter in the PS converter is not used to filter the command in conentional sense. The filter is used to make a system solvable. The solver often need to know the velocity and acceleration when position is specified. Second order filters are used to generate velocity and acceleration.