What Pushed You Toward Mecanum Drive This Season?

[archer003]

Originally Posted by viking

This is our fifth year as a team, and we have wanted to use the mecanum wheels. So....with this years game needing agility, we went for it.

I'm not sure if there's much difference between the sets, but 1982 is using Andymark Omni-wheels. I've seen the mechanum wheels, but the only diffrence I've noticed are the rollers on the Omni wheels is parallel to the front of the bot, while mecanum wheels are at an angle.

[Chris is me]

Originally Posted by archer003

I'm not sure if there's much difference between the sets, but 1982 is using Andymark Omni-wheels. I've seen the mechanum wheels, but the only diffrence I've noticed are the rollers on the Omni wheels is parallel to the front of the bot, while mecanum wheels are at an angle.

Omni wheels are used when you want to make part of your drive have reduced friction in the direction the wheels aren't driven. Mecanum wheels are used to make a drivetrain that can roll in all directions. Omnis can be made to do something similar if mounted at angles, but usually aren't.

[onecoolc]

Originally Posted by Chris is me

Omnis can be made to do something similar if mounted at angles, but usually aren't.

The drive you're thinking of is Holonomic, which has four omniwheels, one on each corner and each at a 45 degree angle. It was used by Team 417 at the FTC competition this year.

[thefro526]

Chris,

While we are not using Mecanums this year, the thought did come up in our brain storming sessions. A Mecanum Drive theoretically should make gathering balls much easier because you don't have to do as much rotating to keep the ball in place relative to your robot. Also, Mecanum Drives give you additional maneuverability to move around defenders while maintaining the same heading. (Easier to aim and keep ball)

Why kept us away from Mecanum was CoG issues. Most of the Mecanum Drives here have the majority of their robot's mass elevated over the wheels because suck a large opening is required between the wheels when climbing the bump which causes CoG to be substantially higher than most conventionally built skid steers. (6+ WD) Also, the added expense of Mecanum Wheels and the Additional Transmissions we would've needed were a factor in our decisions...

[the man]

Originally Posted by thefro526

Chris,

While we are not using Mecanums this year, the thought did come up in our brain storming sessions. A Mecanum Drive theoretically should make gathering balls much easier because you don't have to do as much rotating to keep the ball in place relative to your robot. Also, Mecanum Drives give you additional maneuverability to move around defenders while maintaining the same heading. (Easier to aim and keep ball)

Why kept us away from Mecanum was CoG issues. Most of the Mecanum Drives here have the majority of their robot's mass elevated over the wheels because suck a large opening is required between the wheels when climbing the bump which causes CoG to be substantially higher than most conventionally built skid steers. (6+ WD) Also, the added expense of Mecanum Wheels and the Additional Transmissions we would've needed were a factor in our decisions...

We used custom mounts which lowered the center of gravity, no transmitions unless your talking about gearboxes, but it dose eat up your cim limit.