On Wed, 2009-10-07 at 18:52 +0200, Sven Wesley wrote: ... snip > It's an odd combination of this image: > http://www.wallacecompany.com/machine_shop/Shizuoka/mpg_proto-1a.jpg > <http://www.wallacecompany.com/machine_shop/Shizuoka/mpg_proto-1a.jpg>and > the text "The PDF for the opto-interupters is here > (H22L)<http://www.fairchildsemi.com/ds/H2/H22LOB.pdf>.", > and I didn't really understand the combination. But opto couplers are nice, > absolutely. > If I understood your setup, You only have the EMC2 output signal, opto > couplers, amplifiers and then the motors? Sounds like a really clean setup > to me. How fast can you go? > > Regards, > Sven
This picture: http://www.wallacecompany.com/machine_shop/Shizuoka/mpg_proto-1a.jpg shows my experiment at making a cheap jog wheel (or MPG). I failed to notice that you mentioned opto-interrupters as opposed to opto-couplers, which until now, I tended to use the terms to mean the same thing. Sometimes it takes a 2x4 to the head to make me realize the obvious. I can rapid up to 70 inches per minute, so... 70"/min. 5 rev./1" 200 steps/rev. 1 min/60 sec. = 1166 steps/sec. I got this maximum speed by running the axis until I started losing steps, then backed off a bit. The parallel port signals should be able to go much faster. The signals between the original Bandit controller and the stepper driver boards were quadrature, so I just copied what the Bandit was doing, except the Bandit had a clever means to phase in single stepping at higher step rates (>50 ipm). This gave a maximum axis travel rate of 100" per minute. I want to go to servos and 70" per minute is fine for now, so I haven't tried to figure out how to get EMC2 to to phase in single stepping. So basically, there is just a driver chip and some CAT5 between EMC2 and the original driver board and stepper motor. -- Kirk Wallace http://www.wallacecompany.com/machine_shop/ http://www.wallacecompany.com/E45/index.html California, USA ------------------------------------------------------------------------------ Come build with us! The BlackBerry(R) Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9 - 12, 2009. Register now! http://p.sf.net/sfu/devconference _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users