This years 2019 game has an end game element that requires you to climb relatively high platforms. My team is struggling to come up with a drive train or mechanism that will allow us to climb do to the bumpers being in the way. Does anyone have any ideas?
Here are a few good threads already on CD about Hab Climbing
we thought some thing similar buy looking at stair climbing robots or doing tank tread these ideas work however the problem is that the robot needs to hit the front of the platform to catch the platform which it cant do because of bumpers
Lift the bumpers then
If everyone on CD worked together to make their robots identical, that robot would be boring. What’s the point of a challenge if you ask someone else to answer it for you?
If you need brainstorming ideas, look at the Ri3D teams. They usually have a good representation of the early competitions, but rarely come close to what powerhouse teams can achieve. If you still need more ideas, try finding a real-world equivalent of the challenge and see what exists already.
yeah i know just trying get some fresh ideas to get some gears turning
Are airbags mounted on the bottom of your robot legal?
Mounting them is probably legal; I can’t find anything against it and teams use pneumatic wheels all the time. Filling them to lift during the match seems an issue:
- Filling airbags with explosives (like auto airbags) or CO2 cartridges run afoul of R46 and likely R9 and possibly R86.
- Filling them with pneumatic air, I don’t see where this would fit in R84. The only actuators are R84-I:
Pneumatic cylinders, pneumatic linear actuators, and rotary actuators.
- The largest legal [rectangular] robot would be 30"x30", or ~36" square with bumpers. You could theoretically lift a 100 lb robot with a bit over 3/4 psi air pressure. You might be able to fill it with fans if the LRI decides this does not constitute pneumatics, and this sort of device has passed the non-pneumatic criterion in previous years.
- If you come up with a legal way, still don’t deploy them outside the HAB zone if they’ll lift you up to L2 or L3 (G23)
You can put parts of the robot outside the bumpers. You’re allowed 30" from the frame perimeter, and the bumpers only use up a bit over 3".
Reread R26.
I don’t mean to articulate the bumpers, I mean to lift them through the process of lowering things below your bot.
Through a careful reading, lifting the bumpers meets the wording of the rule, as long as it’s vertical movement only, but it certainly violates the spirit of the rule. I’d imagine a team update or Q&A will clear it up though.
I disagree. The rules make it clear that you cannot articulate your bumpers, full stop. R26 allows for the bumpers to go outside of the bumper zone, which would be the case if you were to have a mechanism that lifts your your entire robot, not just the bumpers above the 7.5" max bumper zone.
I have no serious answers so far, but I was thinking (as a joke) you may be able to just yeet (launch) the bot up there with a car airbag. Besides that, I’m pretty stumped as well.
Not that I’d do this, but what if instead of articulating your bumpers, you articulate your frame. You have a large portion of your bot act as the pusher that lifts the robot. Even if that’s still against the rules, it shows that there is a vague middle ground between pushing your robot up and articulating the bumpers, and it’s hard to draw the line in the middle.
The rule specifically calls out articulation relative to the frame perimeter, which is 2d. This is the only reason that I believe the rule as written allows lifting of bumpers (only in HAB zone where the bumper zone is ignored). I do believe that you are not meant to, however
EDIT: R1 in combination with R26 is the key point, which does appear to disallow lifting your bumpers, R26 alone does not prohibit such actions as written
R1 forbids articulation of the frame perimeter, R26 prohibits articulation of the bumpers relative to the frame perimeter; this is further clarified in R31g.
Articulating the drive train and/or lifting the robot on some sort of legs is permissible inside the HAB ZONE; outside the HAB ZONE G23 and R25 severely limit these actions.
The alliance wall is a boundary of, but apparently not a part of the HAB zone, so you can’t attach/pull/hang on it (e.g. with a suction cup).
I have thought of five options (which may be combined), in the order I consider most likely:
- lift the robot on “legs” supported by the horizontal surfaces of the HAB ZONE
- Deploy a ramp for yourself and/or another robot - watch the 30" extension rule.
- One robot lifts another robot, or climbs on another robot
- Articulate some wheels outside the bumper perimeter and drive up like we saw that HumVee do
- Somehow grasp the horizontal surfaces of the HAB ZONE (e.g. the left and right sides of the L3 pedestal) and lift against that.
As a subset of five, I realize that it may be possible to slide something between the alliance wall and the HAB ZONE pedestals and pull on that. That’s likely to be forbidden by a team update.
It seems almost impossible to put yourself on level 3. Our team is thinking about making a scissor lift to lift our alliance partners to the same level and allow them to drive onto the platform.
It’s not impossible, just hard when you consider a typical FRC drivetrain.
Hard certainly but far from impossible. I have a couple ideas, but it’s looking like it’ll take a decent bit of weight, space, and actuators to pull it off quickly and reliably. We’ll see how the prototypes go. Keep your eyes on Ri3D, one of them will probably come up with something functional.