Valid Configuration? Kiwi with mechanum wheels

[z_beeblebrox]

Originally Posted by jkelleyrtp

The vectors don't resolve the same way meaning you couldn't have a perfect left-right strafe. It would be more circular movements, similar to H drive with only the front wheels touching.

Why not? In this force diagram(not to scale), the torques from the front wheels cancel the torque from the back one. The center wheel creates a sideways force while the fore-aft forces from the front wheels cancel.

[GeeTwo]

Originally Posted by z_beeblebrox

Why not? In this force diagram(not to scale), the torques from the front wheels cancel the torque from the back one. The center wheel creates a sideways force while the fore-aft forces from the front wheels cancel.

To obtain a "pure strafe", the wheels at the top of the image would have to apply torque with out actually rotating. It can be done, but it would not just be standard FRC hook up of controllers, motors, gearboxes, and wheels.

[EmileH]

Originally Posted by z_beeblebrox

Why not? In this force diagram(not to scale), the torques from the front wheels cancel the torque from the back one. The center wheel creates a sideways force while the fore-aft forces from the front wheels cancel.

This year 1658 used a similar drivetrain design, except with them having two rear omni wheels for strafing instead of one, and they had the strafe wheels on the front of their bot. A video explaining the drivetrain is here.