2015-05-17 21:22 GMT-03:00 andy pugh <[email protected]>: > In the case of my (experimental) setup it isn't even that good, the > offset sent to the axis takes into account no velocity or accel > limits, and if the spindle speed is too fast then lost steps happen. > > With a servo system this would be less critical, you could light an > LED to warn that f-error was too high and back-off the speed. > > I think this is a case of deciding what you want to do, then working > out how to do it. Every setup I have thought of so far is possible, > HAL is very flexible. > > Well I came with this question because given the fact that a lobe or eccentric have a continuous speed variation for the follower (assuming the rests are not counted since they give zero speed) I guess to machine the shape you can't have fixed RPMs on the lobe and fixed linear velocity for the axis that moves the cutter.
Honestly I'm in the process of understanding all the maths involved in the process that's why I was concerned about what happened between control points with this approach, since I don't really know how the change in commaned motor position is managed by the HAL driver. In you case it was the Hostmot stepper driver. But I suspect that whenever you ask for change in motor commanded position the driver will use it's maximum speed to reach that position, as a servo would do. Is that right? > One neat elaboration I just thought of is a Python script that loads a > shape-file and sets the parameters of a 360-element lincurve component > so you can load shapes from a file. > Well since my idea is to make several profiles, I was thinking about a component with let's say 360 lift values for each degree, and load the component sequentially using g-code with digital and analog outputs to write the 360 values on the component. I didn't tested it yet but that way I could use different g-codes with the lobe data inside them. -- *Leonardo Marsaglia*. ------------------------------------------------------------------------------ One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
