Re: Geckodrive

A truly unstallable motor would have to deliver infinite power.:-)

I call this "the unstallable step motor project" because of its
practical implications. An open-loop step motor has only two options,
run or stall. If stalls while work is being done then more likely
than not that work will be ruined.

This is also true for ordinary servo drives. If overloaded, they
develop a following error; if the following error is large enough,
the drive faults-out and the motor stops. Same result.

The "unstallable" step motor will just slow down when overloaded. The
G100 will slow the other axis motors down by the same ratio and your
work will be unaffected. You may not even notice it until after you
oil your machine.:-)

By this definition the motor is "unstallable" in practical terms.


Mariss


--- In CAD_CAM_EDM_DRO@yahoogroups.com, "Graham Stabler" <eexgs@...>
wrote:

>
>
> It seems there is some confusion because it is not unstallable

because

> the system can beat any load and carry on regardless rather it rolls
> with the punches. If something loads the motor such that it cannot
> carry on at its current speed it slows to get some more torque. At
> the limit I guess it will stop but it won't be trying to go anywhere
> either!
>
> I suppose you could say the definition of a stall is for a motor to

be

> trying to move when it can't. The unstallable drive knows when it
> needs to slow down to keep moving and ultimately when to give up :)
>
> Jack, the resonant type stall dues to the mid band stuff it not the
> kind of stalling that is being refered to as far as I can tell. I
> also beleive that the geckodrives deal with the mid band resonances
> already.
>
> Graham
>