Mecanum Drive Train

[EricH]

Originally Posted by Burmeister #279

i've showed all of the students on the team the various drivetrains that are on CD but i think that the team as a whole is relying too much on the mentors.

Show the mentors as well as the students.

[dtengineering]

Originally Posted by gorrilla

you could use the banebot transmission, they are pretty fast(when directly driven to the wheel) although reliability is an
issue

Sigh... reliability is not an issue with the CIM planetary gearbox from Banebots. At least no more so than for any other gearbox used in FRC. There was a problem with their first batch of trannies, which, unfortunately, got shipped out as part of the KoP two years ago. Banebots went to great expense and effort to fix the problem in time for competitions and has further improved their product since then. Unfortunately it is the nature of (many) people to remember the initial problem, rather than the excellent committment to service and subsequent improvements that Banebots has made. We were one of the first teams to identify a problem in the original KoP trannies, and have since taken advantage of the free upgrade that BB offered to ALL FRC teams and have been running BB trannies on our mecanum for the last two years with no issues.

In fact BB trannies, or other direct connect transmissions (where the wheel is mounted directly to the output shaft) make for, in my experience, the most reliable drivetrain as the most common point of failure... the chain or belt... is eliminated from the system. Just make sure the output shaft is supported on the outboard side of the wheel!

An additional advantage of the BB trannies is that you can order them in a wide range of gear ratios, and can convert from one ratio to another (with some limitations) if you aren't happy with the performance.

Yep. There was a problem with the Banebots trannies two years ago that was quite disruptive. But it is hardly fair to question the reliability of the current trannies given the fact that BB stood behind their product, solved the problem in short order, upgraded over 3,000 trannies for free, and has since improved them even more.

Jason

[Sam2197]

i agree with that. our rookie year we had the banebots as kop gearboxes and we loved them. our robot was pretty quick that year. we are probably ordering them again this year

[gorrilla]

Originally Posted by dtengineering

Sigh... reliability is not an issue with the CIM planetary gearbox from Banebots. At least no more so than for any other gearbox used in FRC. There was a problem with their first batch of trannies, which, unfortunately, got shipped out as part of the KoP two years ago. Banebots went to great expense and effort to fix the problem in time for competitions and has further improved their product since then. Unfortunately it is the nature of (many) people to remember the initial problem, rather than the excellent committment to service and subsequent improvements that Banebots has made. We were one of the first teams to identify a problem in the original KoP trannies, and have since taken advantage of the free upgrade that BB offered to ALL FRC teams and have been running BB trannies on our mecanum for the last two years with no issues.

In fact BB trannies, or other direct connect transmissions (where the wheel is mounted directly to the output shaft) make for, in my experience, the most reliable drivetrain as the most common point of failure... the chain or belt... is eliminated from the system. Just make sure the output shaft is supported on the outboard side of the wheel!

An additional advantage of the BB trannies is that you can order them in a wide range of gear ratios, and can convert from one ratio to another (with some limitations) if you aren't happy with the performance.

Yep. There was a problem with the Banebots trannies two years ago that was quite disruptive. But it is hardly fair to question the reliability of the current trannies given the fact that BB stood behind their product, solved the problem in short order, upgraded over 3,000 trannies for free, and has since improved them even more.

Jason

I know, but thats not all i was considering. has anyone every seen a toughbox fail?

[EricH]

Originally Posted by gorrilla

I know, but thats not all i was considering. has anyone every seen a toughbox fail?

No. However, you can't use them in their unmodified state as mecanum gearboxes and expect speed and maneuverability to be the best. I've seen that firsthand. There are modifications that can be done to improve speed. I don't know how effective those would be when used in a mecanum drive.

[Sam2197]

i agree. last year the toughboxes were really slow. reliable but slow. and i dont think you can speed the up all that much

[Billfred]

Originally Posted by Sam2197

i agree. last year the toughboxes were really slow. reliable but slow. and i dont think you can speed the up all that much

You could, in theory, get a wide range of speeds out of a Toughbox; the easier ways to get that range of speeds tend to involve factors outside of the gearbox itself. (Wheel size, sprocket choice, etc.)

[EricH]

Originally Posted by Sam2197

i agree. last year the toughboxes were really slow. reliable but slow. and i dont think you can speed the up all that much

Originally Posted by Billfred

You could, in theory, get a wide range of speeds out of a Toughbox; the easier ways to get that range of speeds tend to involve factors outside of the gearbox itself. (Wheel size, sprocket choice, etc.)

Or, you can try something like this. For a 6" mecanum, a roughly 1:1 out of the Toughbox wasn't enough last year.

[gorrilla]

Originally Posted by EricH

Or, you can try something like this. For a 6" mecanum, a roughly 1:1 out of the Toughbox wasn't enough last year.

WOW,

[IndySam]

Or you can try AndyMarks new planetary. Had one in my hand Saturday, real sweet. 3.7:1 would work well with the 6" mecanums.

[Cow Bell Solo]

Last year we had used the AndyMark 8" Mecanum Wheels along with the AndyMark Toughbox gear boxes

One thing I didn't see anyone mention, is that when you mount them mount them in a square, so as in the distance from the middle of the wheel is the same front to back as it is left to right, it makes it easier come programming and movement. It makes since when you think of it, the rollers are mounted at a 45 degree angle.