Re: stepper vs servo

Hi,

Sorry, a little typo in the earlier post, now corrected.

Jan Rowland, Troll wrote: <....."feed back" the position information
to the controller (computer, etc.), so, if something
should "snag", the machine will "keep on trying" to get where it was
headed.....Next question? >

Next question:
B
/.
/ .
/ .
/ . 7 steps
/ .
/ .
/.......
A
7 steps

Suppose a servo system is executing G01 X7 Y7.
On the third step Y stalled.
Will X also stall in sympathy or proceed on?
If X doesn't stall at the same time, but proceed merrily for 2 steps
before Y recovered sufficient torque to continue will the path AB
look like this?


B
| y proceed 2 more steps
|
/ y proceed 2 steps
__/
/ .y stalled 2 steps
/ .
/.......
A
7 steps

Please note, at the end of the move, B is still at x=7, y=7 from A,
no missed step, but it is not the straight line intended!

Hope this is incorrect, otherwise the servo may be not that much more
better at avoiding spoilt parts than steppers.

Peter

--- In CAD_CAM_EDM_DRO@y..., cadcamcenter@y... wrote:
> Jan Rowland, Troll wrote: <....."feed back" the position
information
> to the controller (computer, etc.), so, if something
> should "snag", the machine will "keep on trying" to get where it
was
> headed.....Next question? >
>
> Next question:
> B
> /.
> / .
> / .
> / . 7 steps
> / .
> / .
> /.......
> A
> 7 steps
>
> Suppose a servo system is executing G01 X7 Y7.
> On the third step Y stalled.
> Will X also stall in sympathy or proceed on?
> If Y doesn't stall at the same time, but proceed merrily for 2
steps
> before X recovered sufficient torque to continue will the path AB
> look like this?
>
>
> B
> |
> |
> /
> __/
> / .
> / .
> /.......
> A
> 7 steps
>
> Please note, at the end of the move, B is still at x=7, y=7 from A,
> no missed step, but it is not the straight line intended!
>
> Hope this is incorrect, otherwise the servo may be not that much
more
> better at avoiding spoilt parts than steppers.
>
> Peter