getdone - 2021-06-04

I ran a X-Y gantry using codesys CNC.
All codes and setting were same, except of feeding speed. And in a low speed, the SMC_Interpolator ran well with a continuous piSetPosition output; but when the speed exceeded a certain value, the piSetPosition changed stepply, showed in the attached picture.

I tried several tests, here are the results:
When cycle time was 1ms, the feeding speed <5 mm/s, ran smoothly. And speed > 5 mm/s, ran stepply.
When cycle time was 2ms, the feeding speed <15 mm/s, ran smoothly. And speed >15 mm/s, ran stepply.
When cycle time was 4ms, the feeding speed <30 mm/s, ran smoothly. And speed >30 mm/s, ran stepply.

I cannot find why this happened? Some calculation wrong in the FB SMC_Interpolator?

 

Last edit: getdone 2021-06-04