I am running a fork of the latest Marlin firmware on my Mendel90. I am generally very pleased with Marlin and the smoothness of motion which translates into high quality prints. One issue though is bothering me - when small circles or tight curves are printed I can hear (and feel) a distinct "stutter" or vibration from the motors. My guess is that the tight curve is a sequence of small segments that are too curved to allow full speed, so Marlin breaks for each vertex and then accellerates again - maybe 20-30 times a second - which shakes the printer. With higher speeds this happens for larger curves as well. The consequence is that the finish is ruined as each stop leads to a slight overdeposition and the acceleration a sligth underdeposition.
Is this a known problem and is there any setting to regulate it - e.g. by filtering out high frequency speed changes?
