At 06:29 PM 9/17/99 -0400, you wrote:
>All the r/c type servos I have are rotational. Do they make a small linear
>servo that is driven like a r/c servo?

They used to.  In fact, back when size didn't matter, they had both linear
and rotational outputs on the "standard" size servo.

But that was the 1970's.

If you are using it to control a servo, go with something like a sail winch
style head instead of the arm type.  Basically, you wind the wire around a
bobbin.  This will keep things linear for you.  If you go with the arm,
things aren't linear.

You can always try asking fred@fmadirect.com - he helped design the
encoder, decoder, and servo chips that made the original IC-based RC
systems.  He also stays pretty current on what's available.

You are probably going to be looking at "quarter scale" servos for torque
needed on a decent spring-loaded throttle.

Andy

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