202,200 for the outside spline and the flex gear is 200. In this situation - the 202 tooth spline is stationary to the stepper. The 200 tooth outside spline is mounted to the faceplate. In this layout - the ratio apears to be 101:1
In this situation the stepper motor and the face plate spin the same direction. With the same set of outside spines swapped - the ratio is 100:1 I am sure Andy can explain it. It doesn't make sense to me. Happy with runout... https://www.youtube.com/watch?v=eLyP2YwdstQ sam On Mon, Mar 22, 2021 at 12:58 AM John Dammeyer <jo...@autoartisans.com> wrote: > > > > From: Sam Sokolik [mailto:samco...@gmail.com] > > So..... interesting.. I just swapped the gears.. Before my ratio was > > 100:1. Input scale was 1600step/rev * 100 = 160000/360 = 444.4444444 > > input scale. > > > > Now I reversed the outside splines. I thought - wow - I must be losing > > steps - but i would aways come back to zero. Finally though - maybe the > > ratio was now 102:1 - no. over shot. > > > > so the final solution seems to be 101:1 WTH? > > > > sam > > Hi Sam, > I found this at: > https://www.engineeringclicks.com/harmonic-drive/ > > "The rate of rotation is dependent on the rotation of the input shaft and > the difference in the number of teeth between the flex spline and the > circular spline. The flex spline has fewer teeth than the circular spline, > so it can rotate at a much reduced ratio and in the opposite direction than > that of the input shaft. The reduction ration is given by: (number of flex > spline teeth – number of circular spline teeth) / number of flex spline > teeth. So for example, if the flex spline has 100 teeth and the circular > spline has 105, the reduction ratio is (100 – 105) / 100 = -0.05 which > means that the flex spline ration is -5/100 (minus indicates the opposite > direction of spin). The difference in the number of teeth can be changed to > accommodate different reduction ratios and thus different specialized needs > and requirements." > > So how many teeth have you on the fixed verses flex gear? And did you by > chance miscount? > John Dammeyer > > > > > > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
