On 10/19/2011 11:10 PM, Tom Easterday wrote: > On Oct 19, 2011, at 12:47 AM, Dave wrote: > >> Tom, >> >> If you try that software and get stuck, drop me a private email. I go >> through Ann Arbor once in a while. >> I'm northeast of Fort Wayne, IN. I'm very familiar with Ann Arbor. I >> grew up in Plymouth, MI and still have family in the area. >> >> I'm guessing that you will need either a 5:1 or 10:1 reduction to make >> that work. >> Keling had some inexpensive (relatively) Nema 34 in and out gear boxes >> for sale the last time I looked that might solve your problems. >> > Thanks for the software link and the offer of help, Dave! I appreciate it > and will let you know. > > We have made some progress today. We had pretty serious noise problems which > were introducing extra steps and causing an accumulation of following error. > It turns out this is why it was faulting in a specific position, because the > distance was just right to amass enough ferror after moving the full length > and back to that spot. We spent the day experimenting with different noise > reduction options and have come up with what we think is going to work for > our step/dir lines. > > I played a little with the software, it looks quite useful and I wish we had > known about it at the start. We are looking into other pinion options to > increase our gear ratio which will allow us to run better at slower speeds. > But we can run as is for now we think - at least from what we saw today. > That may change tomorrow though considering how this has gone so far… > > -Tom > >
Ideally, if you want to wring the max. power out of your servos; you usually want to have your servo motor geared so you are running at the fastest motor speed possible, just before the torque curve falls off, when you are at rapid speed. That way you have full torque for accel/decel at rapid speed plus you are getting max hp/kw out of your servos. In the real world that may not be practical. Sometimes it makes more sense to go to a bigger servo motor with greater inertia and minimize the gear reduction since gearboxes are expensive. That is one reason why the servo companies offer both low and high inertia servo motors. Some of the high inertia motors have a max speed of only 1000 rpm but they have a lot of torque and a larger diameter rotor (higher inertia) to avoid inertia mismatch problems. This is the Automation Direct SureServo page on servo sizing. http://www.sureservo.com/sizingconsiderations.htm If you download this software you will find the same Cooperhill software but with only the SureServo motors loaded in the motor library. The link I sent before has motor data from many manufacturers loaded into it. Dave ------------------------------------------------------------------------------ The demand for IT networking professionals continues to grow, and the demand for specialized networking skills is growing even more rapidly. Take a complimentary Learning@Ciosco Self-Assessment and learn about Cisco certifications, training, and career opportunities. http://p.sf.net/sfu/cisco-dev2dev _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
