Hi Guys
Thanks for all the info, if you have more please keep it coming.
In my application I need to move, not necessarily to a position, but in
a direction, another sensor will tell me when I reached it (switch or
similar), and then I need to stop at that position until I need to move
again. Mechanically I want to use the servo, but I think I need to throw
away the electronics in it and build my one controller, hence the need
for info on the servos. When I looked at ways to control a DC motor one
of the ways to brake it was to turn on both bottom or top transistors on
the H bridge and that should short the motor and brake it. Any views on
that technique welcomed.
Best regards
		Luis




-----Original Message-----
From: piclist-bounces@mit.edu [mailto:piclist-bounces@mit.edu] On Behalf
Of David Minkler
Sent: 13 July 2005 23:13
To: Microcontroller discussion list - Public.
Subject: Re: [OT] R/C servos control

Robert,

That was my experience as well.  I'm surprised you were able to operate 
as high as 300Hz.  It's amazing how much performance you can get for 
around $10US.  I got enough torque to break a bell crank.

Dave


Robert Rolf wrote:

> David Minkler wrote:
>
<snip>

>> Without independent feedback of position information, you would 
>> almost certainly get worse performance.  I think the key here is 
>> 'could'.  You could also increase the frame rate or the supply 
>> voltage (within limits in both cases) and achieve improved 
>> performance.  Too much of a good thing isn't a good thing.
>>
>> Dave
>
>
> Given that my application required all the performance
> we could get from a cheap servo (least latency),
> I ended up running it at 300 hz, which was near the upper
> bound for the electronics seeing the pulses.
>
> Fortunately the duty cycle (changes) was fairly low so the servo
> stayed cool. And we also tried raising the supply voltage,
> and it helped, but not enough to warrant the extra
> regulator (frame rate made a bigger difference).
>
> Robert
>
>


-- 
http://www.piclist.com PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist

-- 
http://www.piclist.com PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist