Re: [CAD_CAM_EDM_DRO] Re: emc and following error problems

Ray wrote:

>>First ting eh. Unable to move an axis at any speed is a good clue that
>>something big is amiss. I'd vote for the parenthetical part of #1
>>first., #3 second. #2 is in there so you don't go to sleep waiting for
>>it to go.
>>
>>4 - Deadband is way big. Half a mm is specified and that sounds more
>>like backlash but it won't run well with that much lash in the file.
>>Half a pulse for deadband is okay although Paul recently said take two
>>pulses.
>>
>>

Thank you, Ray. I missed this entirely! He would have to specify a
move of 80 mm before
any motion would be commanded from the motors! No WONDER it isn't moving!

In fact, deadband is a very dangerous thing, as it introduces a
non-linear transfer function
inside a control loop. I would recommend setting deadband to 0.0 in all
cases.

I have a separate thing in the code that essentially provides a deadband
to prevent servo hunting.
It puts the rate generators in stop if the "voltage" is commanded to be
less than an absolute
value of 0.001 The simulated DACs go from 0 .. 10 V, so that is .0001
of max velocity.

Jon