[simpits-tech] Pneumatic controllers

[Matt Bailey]

This is indeed something I quickly realized when considering using a servo to 
control a valve, or to control the altimeter needles directly........the 
servo just isn't precise enough. I think the bottleneck in that case would be 
the mechanics of the servo. As precise as R/C servos are, they're still 
designed for ~90* of rotation, not adjusting a valve precisely within a few 
hundreths of a PSI, or rotating an altimeter arm 7,000* precisely.

From my brief tests with the quad controller it sure looked like it was 
spitting out plenty of res, judging from the motion of the servo. My "plan" 
isn't really fancy or anything....just hack a servo to output variable 
voltage. But since Craig is familiar with Phidgets and servos, I have to 
assume he's considered this. My guess is that the regulators themselves just 
don't provide the needed precision, regardless of how fine the control 
voltage is.....unless you spend the big bucks for fancy regulators.

	-Matt Bailey

On Friday 25 February 2005 23:55, Joseph Fagner wrote:
> I seem to recall someone over there saying that getting the proper
> resolution was not easy and/or cheap.  It was a while back and I'm just
> going off the top of my head.  It might have been Craig but I honestly
> can't remember.  But I seem to think this was somewhat of a hurdle in this
> project.  Maybe your method tackles that.
>
> Jay