I mean two jack shafts with the belt fixed to the gantry and the servo driving a jack shaft.
JT On 9/11/2015 1:40 AM, Milosz K. wrote: > If you mean by an open ended timing belt that is fixed at both ends and the > motor is traversing along the belt then, yes. One glaring omission in my > initial reply was not accounting for a speed reduction. I'm guess there > will be one between your servo and timing belt pulley. In that case you > have to account for speed reduction: > > w/N > alpha/N > Jreflected = ((gantry m + motor m) * R^2) /N^2 > Jt=Jreflected + Jmotor + Jreducer > Trl=(Ffriction * R)/(n*N) > > 2015-09-10 9:55 GMT-04:00 Dave Cole <[email protected]>: > >> Yes. >> >> On 9/10/2015 7:36 AM, John Thornton wrote: >>> It's a timing belt drive, would that be close to a rack and pinion? >>> >>> JT >>> >>> On 9/9/2015 11:58 PM, Milosz K. wrote: >>>> John, >>>> >>>> Assuming this is a rack & pinion type configuration: >>>> >>>> angular v (w) = linear vel * pulley radius (R) >>>> angular accel (alpha) = linear accel * R >>>> Jreflected = (gantry mass + motor mass) * R^2 >>>> inertia total (Jt) = Jmotor + Jreflected >>>> Torque reflected (Trl) = (Ffriction * R)/efficiency (n) >>>> Torque peak(Tp) = Trl + ((Jt*alpha)/n) >>>> P = Tp*w >>>> >>>> >>>> >>>> >>>> >>>> >>>> >>>> 2015-09-09 14:12 GMT-04:00 John Thornton <[email protected]>: >>>> >>>>> Thanks for all the info, now to chew on this a bit. >>>>> >>>>> JT >>>>> >>>>> On 9/9/2015 5:53 AM, John Thornton wrote: >>>>>> I need to calculate the power needed to move a gantry. I assume that >>>>>> mass and velocity and acceleration are the key factors. Knowing those >>>>>> how do you figure out the watts needed. This is not a milling machine >> so >>>>>> no cutting forces need to be taken into effect. I'll be moving the >>>>>> gantry with timing belts. >>>>>> >>>>>> Thanks >>>>>> JT > ------------------------------------------------------------------------------ > _______________________________________________ > Emc-users mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/emc-users ------------------------------------------------------------------------------ _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
