Newsgroups: comp.robotics
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From: n-egerto@eggs.csm.uwe.ac.uk (N Egerton)
Subject: Speed control of PWM servos.
Message-ID: <1995Feb2.112357.9961@pat.uwe.ac.uk>
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Organization: University of the West of England, Bristol
Date: Thu, 2 Feb 1995 11:23:57 GMT
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I have inherited a project that uses the Intel 80552, a derivative of the 8051, to control a robotic arm. 
This arm uses Pulse width modulated servos. The kind used in remote control models. 
 
My problem is that when the 80552 updates the servos, they move *very* quickly. 
What I need is some way of getting them to accelerate up to full speed, then to decelerate to a stop, 
as they approach their final position.
 
I cannot use the PWM outputs of the 80552, because I have four servos to control so 
I am using a combination of Timer T2, and the ports P4.0 to P4.3.
 
Has anyone had any experience in controlling PWM servos in this manner, and can you give me a few hints?
 
The servos used in this robot, are Futaba Model FP-S148, and again any info on these would be welcome, 
as data on these seems as rare as rocking horse sh*t. 
 
Thanks. 
 
Nick Egerton <n-egerto.csd.uwe.ac.uk>
