off center 6WD help

[Gaurav27]

Originally Posted by EricH

Oh, and you can easily have a 6WD that turns without bouncing or drop. Stick omni wheels on one end.

Eric mentioned omni wheels. Just thinking aloud here...
Should omni wheels be on the end where CG is greater or less than the other end? The end that has a greater CG would remain on the ground for most of time where as the end with less CG. So the end with omni wheels will help in turning and thus should be on the end with a larger CG.

[Madison]

Originally Posted by Gaurav27

Eric mentioned omni wheels. Just thinking aloud here...
Should omni wheels be on the end where CG is greater or less than the other end? The end that has a greater CG would remain on the ground for most of time where as the end with less CG. So the end with omni wheels will help in turning and thus should be on the end with a larger CG.

When using omniwheels, you'd typically eliminate the "rock" from your 6WD -- and so both ends are on the ground at all times.

Assuming that you have four traction wheels and two omniwheels, you'll want for your center of gravity to live above the traction wheels, not the omniwheels. Increasing the total percentage of the robot's weight acting through the traction wheels increases your tractive force compared to placing it over typical omniwheels because the omniwheels have a lower coefficient of friction.

[Stu Bloom]

Originally Posted by Madison

When using omniwheels, you'd typically eliminate the "rock" from your 6WD -- and so both ends are on the ground at all times.

Assuming that you have four traction wheels and two omniwheels, you'll want for your center of gravity to live above the traction wheels, not the omniwheels. Increasing the total percentage of the robot's weight acting through the traction wheels increases your tractive force compared to placing it over typical omniwheels because the omniwheels have a lower coefficient of friction.

Not necessarily ... especially on carpet - the edges of the rolling elements on the omni wheels could "dig in" to the carpet more and actually give you increased traction for "driven" omni wheels. Lateral/turning, of course, is another story completely ...