On Sat, Nov 15, 2008 at 06:26:51PM +0100, Ádám Novák wrote: > Would geckodrives work with EMC2 for example with an I/O board > that creates STP/DIR signals to drive the motor?
You can use "step+direction servos" hooked to the parport with emc, but this has two big drawbacks. First, on dumb I/O like parport, you're limited to fairly modest step rates. Taken together with the 1/10 microstepping of geckodrives gives a very limited top speed. (if you use hardware step generation like ppmc or mesa, then the speed limitation isn't likely to be an important consideration) Second, you give up the ability of emc to "close the loop"; you're stuck with whatever the driver does in terms of deciding when to fault; you have to adjust trimpots instead of values in software; and it may be difficult to get a good reading for following error during the tuning process. > Now, I understood what board and what kind of signals I need to control a > servo motor, however I found only professional amplifiers that would cost > too much. Could anyone hint me where to look for low cost but still reliable > amplifiers? What voltage and amperage rating are the motors? Jon Elson's PWM Servo Amplifier is higher voltage than the G340 (same amperage) and essentially the same price. ($1 more for the PWM Servo Amplifier) Mesanet.com's has 100W (quad), 150W (dual), 400W (dual) or 2kW (dual) servo amplifiers ranging from $22/axis to $150/axis Of course, these are intended as part of a smart I/O system with either the pico-systems USC or a Mesa FPGA card in the mix; that adds to the total system price, but overall it makes a much better system without the limitations that software step generation imposes. Jeff ------------------------------------------------------------------------- This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
