Tank treads

[Bluejackets]

we need to find out how to design and build a tank tread for our robot please help
Thanks

[Mike Marandola]

Originally Posted by Bluejackets

we need to find out how to design and build a tank tread for our robot please help
Thanks

I would advise against tank treads. Is there any reason you want treads and not 6/8 wheel tank drive?

[EricH]

Originally Posted by Mike Marandola

I would advise against tank treads. Is there any reason you want treads and not 6/8 wheel tank drive?

I think he's trying to get help for their offseason robot.

[Bluejackets]

treads are better with inclines and tend to stay level better on an incline such as the one in this years game

[EricH]

I really hate to do this to you...

PROVE IT. Prove your last statement.

I need an awful lot of evidence, after seeing 8WD, 6WD, 4WD, sometimes a 2WD, Mecanum, swerve, octocanum, Nonadrive, AND H-drives all handle ramps that are far steeper and higher than this year's 2" high, 16-degree ones. With ease. Without tipping over.

[asid61]

I would agree that it might be easier to use tank treads for the humo, but wheels will work fine too.

[Bluejackets]

well considering if we do a 4 tread tank drive and the front treads will go up the slope before the body of the robot will and the body of the robot will stay level with the ground with the support of the back treads we can stack a tower of totes on our robot and not worry about the incline and have a device to push the tower of toes onto the scoring platform with ease

[EricH]

Wait, what? Stop, think, RETHINK.

First, you're only dealing with a 2" platform. That's nothing. I've seen robots go up far steeper, far taller platforms. And if you're targeting the STEP, then you shouldn't be going on there at all. (And I'd still point out that I've seen robots climb that much of a step before.)

Second, the only thing worse than tank treads is >2 tank treads. Tank treads are notorious for breaking or for coming off at the least opportune time. Multiply by 2, and watch your problems multiply by at least 2.

Third, if your front treads go up the slope and the robot is still level, that means you've installed a suspension to KEEP it level. So you've got suspension problems on top of the tread problems (potentially).

Fourth, it's entirely possible to maintain control of a stack of bins without requiring the drivetrain to be level. For example, by building a cage around it.

My advice is simple: Start by building the KOP drivetrain. If you haven't done that yet, do it now. You'll be surprised just how easy it is to work with for building that perfect manipulator.

[Isaac501]

Originally Posted by Bluejackets

well considering if we do a 4 tread tank drive and the front treads will go up the slope before the body of the robot will and the body of the robot will stay level with the ground with the support of the back treads we can stack a tower of totes on our robot and not worry about the incline and have a device to push the tower of toes onto the scoring platform with ease

Tank treads will not fix this "problem". The instant tread pod (whatever you want to call it) begins ascent of the ramp, the pitch of the frame will change, unless you create a controlled suspension system to level the frame.

Take it from a team that mastered tank treads and still hasn't built them in over a decade - it's not worth it.

[Canon reeves]

Tank treads are expensive, add an unnecessary level of complications, could cause you to blow your main breaker, and turns are very taxing on the system and require a lot more of your battery. If you want to keep the robot level and stack the totes, just make your mechanism hold the stacks 3" from the first wheels of the robot, that simple. It's not bad to explore your options, but in this game, a simple kitbot will work much better than it would've last year. Last year custom drivetrains were really useful to withstand the beatings, avoid defense, and traverse the field quickly. This year however, you shouldn't need to build such a robust, and fast drivetrain. The kitbots offer good methods of attaching superstructures, and are a generally good option. If you want speed, you can use two CIMS with the gearboxes in the kit already, if you want control you can write code that gives you a fast and slow option. Team 1114 has a really useful and informative document about this, Here I'd suggest reading it and seriously consider not doing tank treads.

[Kevin Ray]

I have to agree with EricH, don't go there. ESPECIALLY if you haven't played around with them in the off season. Having successfully used them twice in the last 17 years we would NEVER consider them for this year's challenge. In fact, they were the last option even considered.

[Mike Norton]

As another team that loves tank drive and has mastered the power of tank drive this is not the game for them. With all the other wheel configuration out there go with something easier and more moveable. If you really want to run with tank drive do a search on this web site you will see them all.