Mark, It isn't that dire, I don't think. I just think that there are a lot of nuances and compromises. I think if you are willing to live with some compromises it isn't that bad, but then again I am just getting started.
Here is my understanding of what I need so far: A PC to run EMC. I will need a motion control card (i.e the Mesa5I20 or equivalent). I will need a servo amp. I will need a servo/encoder. My driver is the pc with the mesa 5I20 card as long as I get an amp that accepts PWM input. If I get an amp that requires an analog +-10V signal I then need to add a 7I33 daughter card to deal with the analog input the amp requires. If I choose an amp which requires a sinusoidal signal, I am not sure what to do since I haven't shopped for an available solution for that yet. As far as step and direction, yes there are a ton of step and direction and plenty of open loop products out there and to be honest I think that they would be better served being driven by Mach. If you are using an open loop system, or closing the loop outside of the machine control software then that is what mach is really set up for and that is where the product support base is. Rob --- On Sat, 4/23/11, Mark Wendt (Contractor) <mark.we...@nrl.navy.mil> wrote: > From: Mark Wendt (Contractor) <mark.we...@nrl.navy.mil> > Subject: Re: [Emc-users] Motion control cards > To: robertpa...@corseusa.com, "Enhanced Machine Controller (EMC)" > <emc-users@lists.sourceforge.net> > Date: Saturday, April 23, 2011, 3:57 AM > On 4/22/2011 5:26 PM, Robert Pabon > wrote: > > Man my head is starting to spin! No wonder people just > go with steppers and call it a day. Maybe my vision is > clouded by ignorance but it doesn't seem like it should be > that hard to pick up a brushless DC motor, a suitable amp > and make it work. Obviously it would be easier to just buy a > sorted motor/driver, but then it would be easier to buy a > sorted CNC machine as well. > > > > So getting back to the motor amp combination for a > second someone have a look at hese for a minute and tell me > what you think. > > > > This is the motor I am using: > > > > http://www.servodynamics.com/Drawing/23S-IE.pdf > > > > I am using the IG23CS-64-IE2000-S > > > > Servo dynamics recommends the 1224-BLS driver > for this motor. The 1224BL is the comparable amp: > > > > http://www.servodynamics.com/Specs/1224bl_spec.pdf > > > > And here are the amps I was looking at using: > > > > http://www.a-m-c.com/download/datasheet/bd30a8.pdf > > > > Servo dynamics says I am fine driving with either > sinusoidal or trapezoidal. The AMC is trapezoidal. Obviously > need to add a filter card, but otherwise it looks to be in > the ballpark. Opinions? > > > Okay, I'm getting a bit overwhelmed here too. I'm > currently using > steppers on my saw beveler, but have future thoughts of > upgrading to a > servo based system. So, if what Robert shows as > necessary, for one axis > I'd need a servo, an amp, a driver, a bunch of cards for > the pc end of > the affair, an O scope, tons of other test equipment... > > Have I left anything out? ;-) > > I'm really beginning to wonder if it's worth the expense. > > Mark > ------------------------------------------------------------------------------ Fulfilling the Lean Software Promise Lean software platforms are now widely adopted and the benefits have been demonstrated beyond question. Learn why your peers are replacing JEE containers with lightweight application servers - and what you can gain from the move. http://p.sf.net/sfu/vmware-sfemails _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
