John, There are a few motor sizing programs out there and one from Kollmorgen isn't too bad to use. You can download it here (windows): http://www.kollmorgen.com/en-us/service-and-support/technical/motioneering/motioneering/?terms=motioneering
They have an online version that is slow and should load from this page (although it wasn't for me): http://www.kollmorgen.com/en-us/service-and-support/technical/motioneering-online/ I'm not trying to pimp them, just that's a motion program that will work. You can plug in the loads and your mechanics and it'll spit out motor/drive solutions that you can then use to gauge kW's. Be careful to look at what voltage they have the drive running. One thing w/ a gantry is you definitely want gearing to accommodate the inertia mismatch. Sounds like you do w/ belts and probably ball screws. Here is an article talking about inertia mismatch w/ stepper motors: http://motion.schneider-electric.com/technology-blog/stepper-motor-sizing-inertia-matching/ With Servo's, you can go over the 10:1 ratio, but most motor manufactures will tell you not to unless you have a direct drive motor (like a compumotor dynaserve). When you ask why, the answer is always, "it's not a good idea" and you'll get "less" performance. I'm sure they're right, but the question is how much less is okay? Also, the direct drive motors usually have no 'compliance' from couplers or belts so they can handle the mismatch load better. I always wondered why if you have 'enough torque' does the inertia matter, but the experts say that you'll have more oscillation when trying to stop and start your load... Which would be important in a CNC type application. Mark > > Date: Wed, 9 Sep 2015 05:53:08 -0500 > From: John Thornton <[email protected]> > Subject: [Emc-users] Calculate Servo Power > To: EMC Mailing List <[email protected]> > Message-ID: <[email protected]> > Content-Type: text/plain; charset=utf-8; format=flowed > > 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 > > ------------------------------------------------------------------------------ Monitor Your Dynamic Infrastructure at Any Scale With Datadog! Get real-time metrics from all of your servers, apps and tools in one place. SourceForge users - Click here to start your Free Trial of Datadog now! http://pubads.g.doubleclick.net/gampad/clk?id=241902991&iu=/4140 _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
