View Single Post
  #1   Spotlight this post!  
Unread 01-02-2008, 23:35
manderson5192 manderson5192 is offline
Registered User
AKA: Matt Anderson
FRC #0948 (Newport Robotics Group: NRG (pronounced eNeRGy))
Team Role: Programmer
 
Join Date: Jan 2008
Rookie Year: 2007
Location: Bellevue, WA
Posts: 62
manderson5192 is on a distinguished road
Bizarre Mecanum Programming Bug

Hey Guys,

I have tried both my own code and stuff based on what team 357 put on this site and I have encountered the same problem in both cases. The robot will move straight forward and backward just fine. It will even spin in circles in both directions just fine.

Whats bizarre is that when we attempt to just strafe to the side, the robot will travel in an arc and spin slowly one way or the other (depending on which way we try to strafe). The problem seems to be caused by two wheels (diagonal from each other) spinning much faster than the other diagonal pair. Here's the real interesting part, though: the pwms indicate that the 4 wheels should be rotating in their respective directions at the same rates. When we try to strafe in the opposite direction, though, the pair of diagonal wheels that spin faster is the other one and again the pwms (seen via printf) indicate that there should be no problem.

Would someone please explain what is going on and maybe how we can fix this?