> What do you mean by step-response, sorry.

    It's a set of data showing how your system responded
    when you changed the target by "a step".

> I am OK, right now my following error is something like 
> 2-3 minutes of arc

    2-3 minutes of arc tell me you're controlling something 
    rotating and "following error" implies you are trying to 
    control the speed of the rotating thing rather than the 
    position of the thing. Is that right so far?

    You can calculate how much "command" is coming out of your
    control loop by figuring out how large 2-3 minutes is
    in whatever units your control loop is operating in and 
    multiplying by your proportional constand and converting 
    into whatever units your motor drivers use.

    So, if 2-3 minutes is 100 encoder counts (Around a million
    counts per revolution on your output device) and your proportional
    constant is 10, then you'll have 1,000 units of "output"
    That might be 2 Volts, or a 75% duty-cycle PWM output depending
    on how your motor is controlled.

    (I bet you know ALL this already, but I'm not familiar with
    your issues, so please excuse me if I explain too much. I'm
    not assuming I'm any smarter than you at all.)

    After all that, it would be great to know if you are driving your
    motors at 20% or 99% of the hardest you can drive them just to
    see if tuning is even going t make any difference at all.

    I love this kind of stuff.


------------------------------------------------------------------------------
Special Offer-- Download ArcSight Logger for FREE (a $49 USD value)!
Finally, a world-class log management solution at an even better price-free!
Download using promo code Free_Logger_4_Dev2Dev. Offer expires 
February 28th, so secure your free ArcSight Logger TODAY! 
http://p.sf.net/sfu/arcsight-sfd2d
_______________________________________________
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Reply via email to