Go to Post Active control of game pieces throughout all stages of your robot's interactions with it is critical. Never let gravity/inertia control the game piece. If you want a game piece to go somewhere, you MAKE it go there. - Jeremy Germita [more]
Home
Go Back   Chief Delphi > Technical > Control System
CD-Media   CD-Spy  
portal register members calendar search Today's Posts Mark Forums Read FAQ rules

 
 
 
Thread Tools Rate Thread Display Modes
Prev Previous Post   Next Post Next
  #7   Spotlight this post!  
Unread 06-08-2012, 08:38
Chris Hibner's Avatar Unsung FIRST Hero
Chris Hibner Chris Hibner is offline
Eschewing Obfuscation Since 1990
AKA: Lars Kamen's Roadie
FRC #0051 (Wings of Fire)
Team Role: Engineer
 
Join Date: May 2001
Rookie Year: 1997
Location: Canton, MI
Posts: 1,488
Chris Hibner has a reputation beyond reputeChris Hibner has a reputation beyond reputeChris Hibner has a reputation beyond reputeChris Hibner has a reputation beyond reputeChris Hibner has a reputation beyond reputeChris Hibner has a reputation beyond reputeChris Hibner has a reputation beyond reputeChris Hibner has a reputation beyond reputeChris Hibner has a reputation beyond reputeChris Hibner has a reputation beyond reputeChris Hibner has a reputation beyond repute
Re: Are we still using only 256 unique PWM steps?

Quote:
Originally Posted by Michael Hill View Post
I'd disagree that 8 bits is enough...
8 bits is more than enough for FRC, especially considering the PWM signal is actually a 1 bit signal.

You can get more resolution than 8 bits if you modulate the PWM command properly. For example, if you want 9 bit resolution you can alternately add and subtract a half bit from every output. For example, let's say you really want an output of 132.5. In that case, send 133 one sample and 132 the next sample (over and over again) and the electronics and mechanics of the system will act just as if you're sending 132.5. Of course, this depends on the system "time constant" being much slower than the rate you are outputting PWM commands (which it usually is for an FRC robot). If you want more resolution than that, you can create a fancy algorithm with a counter and a threshold, which is how PWM is actually implemented in many cases.
__________________
-
An ounce of perception is worth a pound of obscure.
Reply With Quote
 


Thread Tools
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -5. The time now is 23:04.

The Chief Delphi Forums are sponsored by Innovation First International, Inc.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.
Copyright © Chief Delphi