Subject: 
  | 
            Re: What is the best way to eliminate mechanical error trough software
  | 
             
            Newsgroups: 
  | 
            lugnet.robotics.handyboard
  | 
             
            Date: 
  | 
            Tue, 12 May 1998 00:47:24 GMT
  | 
             
            Original-From: 
  | 
            Will Bain <willbain@cs.umt&AntiSpam&.edu>
  | 
             
            Viewed: 
  | 
            2182 times
  | 
              
     |      | 
             |       |  
      At 03:38 PM 5/11/98 -0400, Darkman wrote: 
> The problem is that one of the motors is 2 RPM slower than the other  therefore the robot tends to drift toward the side of the slower motor. 
> I have a few ideas on how to accomplish this, but two heads are better than 
one, so I'm looking for some input to help me write an efficient program to 
keep the robot moving straight. 
 
I handled this type of problem by creating a new process that simply 
monitors motor speed settings and encoder counts (global variables), and 
changes a speed setting in proportion to the difference between the encoder 
counts of the two drive wheels.  There's a global speed setting for each 
wheel, and a third global that represents the desired "throttle" setting. 
To go forward in a perfectly straight line, simply change the throttle 
value.  The monitor process periodically checks this throttle value and does 
whatever is needed to achieve the desired encoder counts on each wheel.  It 
also determines when a wheel is stalled.  My robot zigs a little bit at 
first, and then tracks straight as an arrow. 
 
--Will 
                                          , , 
        __@_/             \_@__           |/ 
          |                /__,           o             @_/ 
          )\              )              ( \            (\/\\, 
~~~~~~~~~ ' ` ~~~~~~~~~~~ ` ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 
Wendy Parson,           The real problem is not whether machines think, 
Will Bain,                                          but whether men do. 
& Tatoosh                                               --B. F. Skinner 
 |  
       |  
           
   
      1 Message in This Thread:    
 
      - Entire Thread on One Page:
      
        
- Nested: 
        All | Brief | Compact | Dots
        
 Linear: 
        All | Brief | Compact
           
         | 
        
  | 
      
 
   | 
           |