New Banebots p80 Improvements

[Madwolvez]

last year (2007 ringer year) all teams received the GP-56012 gearbox model. They had some great features such as simple mounting, compact, encoder option, and provided a bearing block for the end of the shaft to support the load. The problems that occurred with this model were mainly with the carrier plate that would round itself or "bow-tie" as some would call it, and some screws holding the gearbox together would fall out.

So can we trust Banebots for this year (2008) and future years?

YES ......I and a few other believed in banebots so much we were going to purchase them ourselves and sneak them in as a donation since our overlords said no but after a few well placed attacks they folded. The gearboxes would prove themselves at Nasa VCU where the carrier plate after some hard battles showed no sign of "Bow-tie". The encoders providing excellent robot feed back for hybrid mode and such other things. The new assembly method would ensure that no screws were lost and for easy repair.

Now for their final test they will travel to Nationals in Atlanta, Georgia.

[Teched3]

Yes, they have been much improved. In addition, the carrier plates are harder and 1 mm thicker(5mm), the pins are the correct length, and they added tie bolts to hold the end plates flat against the transmission housing.

[lynca]

I'm curious to know how other teams fared with BaneBots P80 this year ?

We have been using the RS-540, RS-550 gearboxes and they have been working great.

[Daniel Bathgate]

We've had no problems with the four 12:1 P80 gearboxes that compose our drivetrain. We also had no problems with the KOP gearboxes last year. Since in addition to the drivetrain we have a 36mm 64:1 and a 42mm 48:1 gearbox on this year's bot, do we win for the most BaneBots transmissions on a FIRST robot?

[Billfred]

At the risk of this being a bump post, I'd like to hear any other P80 stories teams may have. Is my fear of BaneBots unjustified?

[Nikhil Bajaj]

Originally Posted by Billfred

At the risk of this being a bump post, I'd like to hear any other P80 stories teams may have. Is my fear of BaneBots unjustified?

We didn't use the P80s this year but we did use the RS-550 on one of their planetary gearboxes, and we had a couple of different ratio options. All worked perfectly. We ran them close to their rated torque, too, and they did just fine. With what I've heard about the company's products this year in general I'd say they're probably a pretty safe bet.

[Qbranch]

Just as a kudos-to-banebots type post, we used a pair FP motors mated to the RS-550 gearboxes mated to a custom single-stage reduction gearbox to drive our arm up and down. The arm could lift the ball from the floor to the shooting position in about 3/4 second, and we never had a mechanical faliure all year.

However... one odd thing... the tube that makes up the body of the gearbox would turn a bit one way or the other as the torque flipped directions. Just kind of unnerving...

But, wow, for the price? Great!

-q

[ZZII 527]

Originally Posted by Billfred

At the risk of this being a bump post, I'd like to hear any other P80 stories teams may have. Is my fear of BaneBots unjustified?

We used four of the new P80s with a 9:1 ratio for a mecanum drive base. Very fast and zero problems. Axial alignment issues have been solved. Gears are much stronger. And most importantly, the final stage carrier is now a hardened steel. (I tested it to be ~C30 on the Rockwell scale. The old ones were so low they weren't even really on the C scale.)

They still need to be assembled carefully, broken in, and mounted well, of course. Here's a pic of our mounting setup:
http://web.mit.edu/scolton/www/bb.jpg
I'd want to do some careful analysis before using the higher (non-drive, greater than 16:1) ratios.

Last year I did a lot of testing with the old model and it convinced me that I'd probably rather have a gearbox with problems I understand than a new one I've never used. But overall the product line is much improved now. They've also uploaded much better drawings and support documentation. So definitely still useful for FIRST and other applications, IMO.

[T3_1565]

we used four p80 12:1 Transmissions on our Linkage Drive. THe linkage involves stresses not normally seem in a drive train (there is some side load when the wheels switch, thankfully omni wheels make that minimal) and our transmissions held out fine, and still hold out fine! We had one problem with the drive shaft slipping, but that was our fault (we took that one apart and forgot to add the compression ring back on it )

I think these transmissions are awesome, they are so easy to mount, and for linkage drive, thats the most important thing!!

EDIT: Here! This is the pic of our drive train and out mountings (notice the lack of support on the other side of the drive shaft, and it still ran fine!!

[Warren Boudreau]

I don't know the part number, but the 256:1 gearboxes inhaled audibly.

The last stage was constantly shearing teeth off of the planetary gears.

They should never have used brass gears for the final stage of reduction.

Too much torque.

[Billfred]

Originally Posted by Warren Boudreau

I don't know the part number, but the 256:1 gearboxes inhaled audibly.

The last stage was constantly shearing teeth off of the planetary gears.

They should never have used brass gears for the final stage of reduction.

Too much torque.

Warren, to be sure--are you referring to the CIM gearboxes? Those had a warning on the item page, which makes me think that shearing off planet teeth was actually a feature (in that you could install new planets rather than having everything seize completely as they did in 2007). I'm not sure whether that was the case for the smaller gearboxes, as BaneBots has apparently pulled them from the site.

[Bob Steele]

We used a pair of the 42 mm gear boxes mated with FP motors to bring our lift up and down. Initially we had some issues in Portland for several reasons.

The two motors had to drive in opposite directions because of our design and there was some type of stall activity (perhaps a looped line or something) that caused on side of the gear box to not be able to turn. This "allowed " the other gearbox to grind the non-moving one to pieces. Unfortunately this caused massive shearing of the gear teeth in both gear boxes. Also, unfortunately, this occurred in the quarterfinals requiring us to withdraw.

When we assessed the issue, I don't believe that we felt it had anything to do with any inadequacy in the gearboxes. We redesigned the lift and stiffened up everything and rebuilt in Seattle and we NEVER had another problem.

We have talked to Banebots about this and some other issues and they have told us that they are going to use steel gears next year in these transmissions.

We felt very happy with the gearboxes and the number of different ratios certainly gave us several options.

We would certainly continue to use these transmissions in the future.

One interesting note is that the motors that were running the transmissions that ate each other up were not damaged at all...

We really felt that the FP motors this year were very robust. I believe that they had thermal overload built in and that made a huge difference compared to years past. Even though the FP and the 550 had very similar motor curves, the FP motors were definitely more robust and able to handle stall conditions much better than the 550's.

These gearboxes are available on the website but listed under gearmotors and not gear boxes.... they come with a cheap 550 motor which does not have a fan.. These should be removed and replaced with a kit motor. either the 550, the FP or the 540 motor.. I would not suggest that you should use the 550 motor that is included with the gearboxes from Banebots.

We would definitely recommend the 42 mm gearboxes in the future to other teams. They are easy to mount and IF used with the proper engineering considerations, very useful and robust.

[Warren Boudreau]

They were Banebots. I had to run all over the pits in Atlanta to beg for replacements from teams.

[Lavapicker]

We used four P80 12:1 gearmotors with CIM's for our drive this year. We didn't have one problem with them and that's after attending SVR, Hawaii and Atlanta....41 official matches. I was very happy with them!

[PhilBot]

We used four P80 3:1 gearboxes with 4" wheels. Speedy, but not very torquey. But it was a race, right? We could nearly get 6 lines in Hybrid.

The only complaint/comment was that the actual CIM motor housing diameter is slightly larger than the 2.5" gearbox dimension, so you can't lay the motor-gearbox assembly on a flat plate, without recessing a slot for the motor to recess down into. It only takes about 1/16, but without it, the moter gets cocked up at a slight angle.