Mecanum/sticky hybrid

[Sam2197]

is it possible to run two mecanum wheels on the front of the robot and two sticky wheels in the back. if so would we have a ton of worry about going over the bumps from my thoughts it sounds good because it lets us have a really long base and still be able to turn without having a six or 8 wheel drive or having a narrow base. just wonderin if this is a innovative way of using a mix of two worlds and be succesful or just doomed for failure

[Akash Rastogi]

The entire premise behind using a mecanum drivetrain is to manipulate the vectors from all 4 of the wheels in order to create forward and strafing motion using opposing/complimentary vectors.

A really detailed explanation of the simple physics can be found here.

[Sam2197]

well the idea was that the front two wheels would rotate opposite like they are suppose to and that would create the sideways motion that they are suppose to do. or is this rediculous and im way off in loopy land.

[Chris is me]

Originally Posted by Sam2197

is it possible to run two mecanum wheels on the front of the robot and two sticky wheels in the back. if so would we have a ton of worry about going over the bumps from my thoughts it sounds good because it lets us have a really long base and still be able to turn without having a six or 8 wheel drive or having a narrow base. just wonderin if this is a innovative way of using a mix of two worlds and be succesful or just doomed for failure

Two omni (not mecanum), two traction wheels is a fairly common way to reduce turning scrub, at the expense of one side of your drivetrain being fairly easy to spin.

[Sam2197]

Originally Posted by Chris is me

Two omni (not mecanum), two traction wheels is a fairly common way to reduce turning scrub, at the expense of one side of your drivetrain being fairly easy to spin.

thats why i was thinkin the mecanum. i have heard of the omni's being used. but i was thinking this would provide a little more stability from getting bumped or just driving make it more stable.

[EricH]

It's possible that it would work. If you did it right, you could also get the same effect from cutting 45* grooves into an AM Lunacy wheel tread.

Some time ago, while I was still on a team, my dad and I did a VEX-scale prototype of a rather slick mecanum-pattern drive. There were no rollers involved. Not only did it turn well, it acted like a mecanum in terms of sliding. We never did go full-scale, though, so I don't know if it would work in FRC.

The original intent? Make turning easier. It did have that effect. You don't need mecanum code, either, IIRC. Just the right roller orientation.

If you've got any mecanum wheels laying around, do a quick test with the KOP sticky wheels and the mecanums in a KOP frame, standard drive code, all that sort of thing. That's the only way to tell for sure.

[Sam2197]

yea we'll give it a shot on monday. i dont htink it would require direct drive would it. im not exactly sure at the moment.

[EricH]

Originally Posted by Sam2197

yea we'll give it a shot on monday. i dont htink it would require direct drive would it. im not exactly sure at the moment.

I don't think so. A standard 4WD setup should work well enough.

[Sam2197]

alright thanks for the help.