Homebrew PCBs

On Sunday 12 June 2005 10:37 am, Stefan Trethan wrote:
> On Sun, 12 Jun 2005 15:28:51 +0200, mycroft2152 <mycroft2152@...>
>
> wrote:
> > Hi robert,
> > Hadn't thought of using servos for this, just steppers. But that is
> > an interseting idea. For hobby robots, the servos are modified for
> > continuous rotation. May just be possible.
> > The picaxe has built in servo routines and is programmed in BASIC.
> > Should be easy to hook up a couple of servos to the screws to try it
> > out.
> > Myc
>
> I thing the reference to servos was meant more general, not RC model
> servos.
> They often use DC servo motors on larger CNC machines, for faster speeds
> and more power.
> There is a severe increase in control circuit complexity (you need
> rotational feedback and a closed loop control).

I believe that some of the motors I have salvaged are servo motors -- there 
being only two wires instead of the usually larger number for steppers, and 
also the encoder on one side gives it away.  :-)

> If you do not need to advantages of servos (power and speed) it is MUCH
> easier to go the well tried route of using steppers.

Which is why I plan to use those first!

> RC servos would not last very long, in this application, and would not
> move very fast or with any amount of force. They are more expensive than
> steppers with no advantages, so i would not suggest using them.

To some people those _are_ "servos",  the term having been distorted into tha 
context,  I guess.