Thread: Tank Steering
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Unread 02-09-2009, 23:47
AustinSchuh AustinSchuh is offline
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Re: Tank Steering

Quote:
Originally Posted by biojae View Post
So, just correcting the skid value from an absolute sensor (ex Ultrasonic sensor to a known wall) is all that is required to have accurate readings?
Also on carpet, there isn't as much skidding, so it is not as important then?
As with all engineering, you need to figure out how much is good enough, and how to deal with things not being exactly as planned. Say someone gets between the wall and your sensor? Say someone crashes into your side? Do you care? We chose to just use the ground speed encoders and let someone crashing into our side make us loose track of our real position. For the most part, it worked fine, and it's debatable whether having that information when someone did hit us would have allowed us to do much more. Assuming you tried to add in an Ultrasonic sensor, that would only let you narrow down the potential error in one direction. I'd say just integrate the ground speed encoders, or the ones on your drive train, and use that until you have determined that that isn't enough. Detecting position and using it are isolated things that you can improve independently.

Quote:
Originally Posted by biojae View Post
and your error has what value? current heading - target heading, or something similar?
If you are trying to point the robot in a direction in order to go in that direction, the error is some measurement that is fairly linear and will be 0 when you are pointed in the correct direction. The heading error was what I used when trying to go to a way point.