2012-2013 Drive Trains

Since Bridge Battle 2.0 (sack Attack) now introduces a new element into the vex mix; the sack, which is both a game element but also an obstacle for robots to navigate around. our standard 4 wheel drive trains may not be great overcoming the sacks and may result in robots getting easily stuck so i was thinking what is the most innovative way to overcome the challenge and this poped in to my head along with some other options but nothing that radical so i was wondering what ideas people have for not getting stuck on the sacks (an obvious approach would just design you chassis so the only thing to go below 3 or 4" of your bot is the wheels and manipulatior)

What are your thoughts?

Are coming back into VEX to compete this year? I think that could work. It would have to be perfectly set up though.

Why would you need to drive over the sacks. Just pick them up.

I may, but i don’t think its likely, i don’t have a team or the resources to start my own but you never know what the future holds. I think its a very possible solution but not really practical but I’d love to see someone build one

It would work, but seems irregularly unsteady and might be a pain to turn quickly and fluidly. It would sure be a head turner though.


I would say either raise up your chassis so that enough wheel is exposed to climb and drive over the sacks, or have it really low to the ground with some sort of plow. Legs could work but I’m not sure how practical they would be. Maybe something like this? Although I’m not sure how well they would work as wheels with a heavy robot.

Lets say another team pushes some near the back of your bot and your facing a wall or your bot is at full capacity as it is or whatever reason it would be nice not to have to worry about getting your bot stuck during the match

yeah but the head turner would be enough reason for me to try it haha #RebuildRonny

the wheels being raised would probably work best but its a concept and maybe if you do it right you can get some awards and such

Some of our students already created a mecanum drive in light of our FRC robot to have a passive suspension that allows the back (or front) wheels to pivot in tandem, allowing the robot to drive over uneven terrain. A few photos were posted here: https://vexforum.com/showpost.php?p=266449&postcount=126

Once we get our sacks we will post video of us attempting to drive over them as we have no idea how well this will actually work on the sacks.

Building a Ripsaw would work.
Opposing robots won’t be an issue either.

it could be an opportunity to use vex suspension from the gallery:

Pneumatic Tread tensioner anyone? :wink:

i actually built one of those last summer, if you get the elastics tensioned properly it’s great (it got right over the round up rings i was playing with)

Unlike gateway, I did not see a rule saying we can’t go over the bridge.

I didnt mean in a form of raising and lowering the robot that would create complex messes of stuff you dont want to deal with. What I was saying was WHAT IF you used a piston with a sprocket on the end of it to tension chains/treads have it always charged so it adapts to the treads slacking and tightening.

Just a thought

  • Andrew

yeah you have fun with that :rolleyes:

yeah but it wouldn’t be that complex if you did it right (i may make a cad model of a chassis that can lower its self) and that idea was on the FRC “Next Year” list (if we arn’t forced to use belts haha)

I think Grant’s vex robot could handle the bridge.

good concept but just a little over the top if you ask me.