Hello List; I have a simple machine that needs a single axis control to rotate a crank shaft 220 degrees then back. I plan to use a NEMA 34 stepper and a Gecko for the motion. I will mount large XL pulleys on the crank and use about a 5:1 reduction ratio.
Limit at one end of the stroke home at the other. I want to use an Arduino to run the thing, but I have not found much info in the area of programing accell curves for the step/dir outputs. I need to program ramp to max, move xxx steps, ramp down to a very slow speed for the last 30 degrees, stop and dwell then ramp to max back to home and stop. I have been searching the Arduino forms and most examples are for users actually trying to control the phase outputs of drives they have built on "shields". Also these users believe in "Instant acceleration" they just start a pulse stream with no ramp up. Floppy drive steppers turning tape flags can kinda get away with that, but I'm driving a load on a Nema 34 and I don't want to pound the crap out of the works. My plan goes like this: Digital Inputs: a} Home switch b} Limit switch c} Jog forward d} Jog reverse e} Start f} menu ? Digital Outputs a} Direction b} step Analog Input - Potentiometer as feed override 0-100% Estop will be all hardware so its not an issue. I ask here because I know a few users have been toying with the Arduino for use as a cheap micro PLC to work with EMC2. I'm just looking for a few lines of code that show how to insert accell / decell ramps into the sketch. I will end up mounting a degree wheel on the crankshaft and adding or subtracting steps as required for best use. Right now it is all done by hand with a lever. I expect running by hand is faster - but slow and steady wins the race and operator ( that would be me) fatigue is always a factor in actual production output. And because Enquiring minds will want to know... The application is a 1964 model (San Diego) Star Lube sizer. :) With all the extra bells and whistles (almost), Base heater, Lube pressure system and bullet feeder. Maybe later I can build a mini Puma robot to sort them. Thanks all. ------------------------------------------------------------------------------ Download Intel® Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
