Drive Systems
 

What drive systems are people thinking about using for this game? It looks like a 6 wheel drive will be best (because of the barrier), but I can see ways to use a mecanum or swerve drive (using the bridge).

Re: Drive Systems
 

A lot of teams are going to go mecanum because of the existence of protected zone, but defense will be aggressive in preventing them from getting there.

I can see 4 wheel tank being viable due to the fact it makes getting ground clearance for the bump easier (see 330's 2010 bot) as well as working on widebody robots.

As with nearly any game, 6 wheel tank is viable and will be the most commonly used drive, and since the kitbot is 6 wheel drop center, FIRST engineers thought it could play the game.

Re: Drive Systems
 

I'm curious if anyone is going to try to build a drive train to actually circumvent the barrier. The only things I can think of to do that would be either rather large wheels or a tread drive (after actually seeing the barrier, normal wheels will likely be an "improbability" :)). Then again, the rules are strict enough in regard to passing over the balance boards (G25, G28, G29) that I doubt there will be a need to go over the barrier. Our team has been developing a 6-wheel drive system that we are pretty happy with, because of the increased mobility over the 4-wheel. However, 4-wheel drives will have a fine time navigating the field as well, I think.

Re: Drive Systems
 

Our team is thinking along the lines of above, but i'm not going to say how much of above :D

Re: Drive Systems
 

I've come up with about 5 or 6 different ways to climb over the 4 inch tall barrier. Are the biggest wheels allowed this year 8 inches? I couldn't find anything in the "The Robot" section of the manual. If so, then I instantly have another half dozen solutions.

Re: Drive Systems
 

We have a way through them. :) How? Watch SVR in 11 weeks and find out!

Re: Drive Systems
 

If you can't find a rule restricting wheels, then wheels should be considered unrestricted. Have at it.

You could always ask the GDC to be certain, but I can only think of one wheel restriction rule (back in '09).

Re: Drive Systems
 

Our team is also coming up with ways to jump the bump, but I'm actually surprised that people think mecanum will be used by a lot of teams. HDPE floors? Bumps? Bridges? Those will not be nice to your poor Swiss wheels.

Re: Drive Systems
 

Have 2 pneumatic cylinders between the front and middle wheels, pointing down. Then, at the press of a button, the shoot out for a second and come back in, lifting your robot into the air, and giving it room to get over the bump.

Re: Drive Systems
 

Who are you, Speed Racer? Do you also have cutter blades, a bulletproof canopy and a homing pigeon? Oh no, the homing pigeon is like a minibot! Arrrrrrghfuuuuuu!

Re: Drive Systems
 

I think octocanum with barrier assist sounds about right for this one... :D

Re: Drive Systems
 

Wouldn't lifting the robot violate the bumper height rule?

Re: Drive Systems
 

I wondering how people are expecting to get the Bridge down from its nuteul position. Any thoughts??

Re: Drive Systems
 

Little t-rex arms in the front of the robot.

Re: Drive Systems
 

Depends on how high you lift the chassis.

Also, you'd need to be careful of 'articulating' bumpers.

Re: Drive Systems
 

What is the bumper height restriction this year. I see nothing in the specs.

Re: Drive Systems
 

R01, blue box


[R01] see the whole rule as trimmed for content......... The Frame Perimeter of a Robot is defined by the outer-most set of exterior verticies on the Robot that are within the Bumper Zone, which is between 2 and 10 in. from the floor. Minor protrusions no greater than ¼ in. such as bolt heads, fastener ends, and rivets are not considered part of the Frame Perimeter.

To determine the Frame Perimeter, wrap a piece of string around the Robot at the level described in [R02]. The string describes this polygon.

Note: to permit a simplified definition of the Frame Perimeter and encourage a tight, robust connection between the Bumpers and the Frame Perimeter, minor protrusions such as bolt heads, fastener ends, rivets, etc are excluded from the determination of the Frame Perimeter.


Why this isn't in the bumper section i'll never know.

EDIT: Howdy neighbor! :-)

Re: Drive Systems
 

Please see:
[R30]
Bumpers may not be articulated.

Re: Drive Systems
 

Exactly why I mentioned it ;)

Re: Drive Systems
 

May our 14" mechanism expand in the bumper zone outside the robot?

Re: Drive Systems
 

I would assume so. My POV regarding this is that the bumper zone is only a bumper zone when there are bumpers present. That sounds a bit confusing, but what I'm saying is, you have your bumpers set with the openings, then you have an arm(or whatever) at the same level as your bumpers, then yes, its seems like you can expand there(if that's what you're asking)

Re: Drive Systems
 

their actually one of, if not the strongest wheels out there (an aluminum and steel sandwich). that said, you probably should use hard rubber rollers, as the soft one might get chewed up. also, u will want 10", because the boards are 4" high...

they never said that the part their attached to can't move...

Re: Drive Systems
 

I don't think so -- any more than driving across a tilted ramp would violate the bumper height rule. The bumper height is clearly relative to the robot, and not to the absolute plane of the court floor, else any ramp action is inherently illegal.

Re: Drive Systems
 

hmmm.... http://www.youtube.com/watch?v=5MgdG...eature=related

Re: Drive Systems
 

Team 610 in 2010 had ~10" pneumatic wheeled 6WD; the middle one rose and lowered so that they had an easier time with the bump. I'll try to find a video, but most of them are low res taken from far away. Anyone have a picture of it? Still my favorite robot of all time.

Re: Drive Systems
 

Done.


http://frc-designs.com/html/CAD_2010.html

Re: Drive Systems
 

This was posted in a different forum. It's a really cool way to drive the robot, but i'm not completely sure how effective it would be for this years game.

http://youtu.be/uaT7M3Nwj7c