Drive Train/mechanim wheels

[Madison]

Originally Posted by Andrew Schuetze

Lil' Lavery - The third and fourth links are not loading for me.
My question for those experienced with mecanum set ups is can they be used on a rectangular base? I don't see an issue with motion in the X & Y directions and maybe the diagonals might be a bit off, but what happens to a zero degree spin in such a situation??

If you build a closed-loop system, you can compensate for the misalignment of the mecanum wheel rollers on a rectangular base. We built an open-loop system and the error created in diagonal movement because of our rectangular base was insignificant compared to the overall error due to variances in motor operation and gearbox efficiency at each wheel.

[dtengineering]

Closing the loop... either with encoders on each wheel, or a gyro, or some other form of control... is necessary to enable the robot to travel in a straight line.

A good mecanum drive is much more challenging than a good tank drive. Read carefully the many threads that have discussed the topic, and then go for it. Very few people have ever seen mecanum wheels in action... and they are usually very impressed by what they can do.

Jason

[AdamHeard]

Originally Posted by dtengineering

Closing the loop... either with encoders on each wheel, or a gyro, or some other form of control... is necessary to enable the robot to travel in a straight line.

A good mecanum drive is much more challenging than a good tank drive. Read carefully the many threads that have discussed the topic, and then go for it. Very few people have ever seen mecanum wheels in action... and they are usually very impressed by what they can do.

Jason

Exactly... they is a huge difference between a team that has awesome closed loop control & programming (team 40 in 2006) and a team that just puts mecanums on the robot.