This game more than any other I’ve seen in FRC has the most interesting strategic options and considerations.
Still correct, people are talking about how to do a lift (as shown in your video) but a lift is not a ramp.
I do hope to see a cross, but man, getting 2 other bots in the right position that they won’t fall or unbalance you is gonna be crazy.
What happens if a robot dies on the field and can’t make it to the scale–can the iron cross climb with an unbalanced load? or do you just leave the other one?
That’s a really good design question. Also, if you have two partners of vastly different weights, can you climb with the iron cross?
I don’t envy teams trying for it.
Some designs can, yes. Some can’t. Just a matter of how you approach the problem. From what I’ve fooled around with thus far, the ones that can carry an unbalanced load will be slightly heavier due to having a few more necessary parts (motors or pneumatics or whatever you may use).
I’m waiting for the inevitable tall robots flipped over on the field that will result from designs like this… :ahh:
IMO it makes the most sense to have bars emulating the one on the field, since presumably the largest number of teams will be compatible with that. If you have a partner that cannot climb, either levitate them, or cheesecake a hook onto them that can attach to your robot while it’s still at ground level and then lift both bots.
If you have a partner that can’t climb. According to the 2016 season stats which featured a very similar if less important climb (with spaces for each robot) roughly 5% of possible scales were successful. So in quals, when you get paired with two non climbing robots I think that teams that can bring someone with them or lift both partners or however they want to get all three climbs accomplished will be the only ones getting that ranking point consistently. Cheesecake is often too much organization and effort to pull off for every match, especially at districts where you may play three times in one hour.
Now wether or not the climb percentage is more similar to 2016 or 2017 is up for debate, but I would be inclined to bet on far closer to 5% than 50%.
One thing that has not been mentioned in this thread is the that 3-robot-climb bonus goes away in Elims. You get an extra ranking point during Quals, but nothing extra during Elims. This raises a strategic question: is worth getting the 3rd robot to climb, or is it worth more point to have it on the field trying to influence the scale/switches. If you can tip one of the balances at 30 seconds before the end, while the other alliance is busy setting up a big climb, then you have gained 30 points, same as a climb.
I think the “Iron Cross” will be quite popular with the top 3% of teams for the extra RP in quals. It’s definitely not something the other 97% should be worrying about though. Tons of engineering effort that isn’t as valuable as the much simpler tasks like scoring on the scale or switch autos.
Would it be worth preparing a cheesecake ramp for elimination to make up for not having a triple climb robot on your alliance? While it might be difficult to design a ramp every team can climb up, it is probably easy to make a ramp your own robot can climb up instead.
My team is going for the strategy of lifting ourselves and one other robot and the third robot gets the levitate. This leaves that last robot to keep doing switchs and scales for the last 30 seconds but still achieves 3 climbs.
I think that very few teams will attempt the Iron Cross, fewer still will end up with a mechanism that can do it reliably, and the tiny fraction that’s left will usually have alliance partners that don’t manage to get where they need to go to pull it off. Double ramps with levitate (or single ramps with one actual climb and levitate) will be fantastically more common and more reliable Face the Boss RPs.
In terms of the robot you want to build, if you’re going to go for specialization rather than an all-rounder, the vast, vast majority of teams would be better off building a dedicated vault/switch bot that can neither score on the scale nor climb at all. If all you do is tackle your switch (135 teleop points, ~28 autonomous points + 1 RP) and feed your vault (45 cube points, 30 climb points, +10-20 points for Boost, +10-20 points for Force for a guaranteed 95 and potential 115 points, 10 of which overlap with switch control), you’re looking at ~60% of the maximum possible score of every game and your share of both bonus RPs.
Filling the vault is worth more than a Face the Boss to the tune of 5-25 points, and it’s an astoundingly easier engineering challenge than an Iron Cross.
Teams amaze me ever year with what they manage to pull off, but for every team that pulls off the amazing, there are hundreds that can’t really play the game to any real level of effectiveness because they tried to pull off the amazing and fell short, rather than focusing on the best robot they can actually build and get practice time on. (Like, say, us last year.)
I completely agree this seems to be the more reliable way to go due to less factors that need to come into play. Some key factors to look into:
I.E = 1. “Iron Cross”, “Upside-Down T” etc - balancing out weight on both sides of robot to be able to lift, compensate for weight differential, a strong enough motor(s) to be able to lift all robots.
2. Ramps- Wide enough for all size robots to climb onto, Can support up to 120lbs+ and have the bumpers "levitate" past the 12" mark. Support for 2 other robots.I know we are a rookie team but we are going to have a linear climbing mechanism to lift our robot about 4 feet off the ground. We are looking at possibly installing a rung underneath our robot so that another team could hook on and lift. Thoughts?
You have to remember most climbers are calibrated to possibly climb on a game rung at game height so engaging on a lower rung securely could be problamatic for some possibly many teams climbers
Also a rigid structure under your bot may not keep your bumper height under 7.5" (bumper zone still applies in endgame IMO)
I think this is why ramp bots seem desirable somewhat easier solution to park on a ramp although High CG bots on a ramp that a recipe for disaster. The other option is to mimic the actual rung (could make it wider) this could also be 3.5" lower since a back climber possibly engage from carpet. Side climb have to worry about balance issues.
The other theory is to use ropes or other flexible stuff (see Q&A #4)… since many teams had rope other flexible stuff climbers in 2017 and would have those laying around.
of these are probably more Einstein than normal games, I don’t expect to see a lot of successful physical Multi-climbs, its hard enough to park 3 bots in 104" with bumpers
My general feeling is this game will be signficant wear and tear on bots (auto collisions, high GG falls tips, defense hammering, ramps/proectors, banging into scale plate wall and switch wall) just a slice below Stronghold…so think durability and spare parts
Another consideration is that many robots will have arms and elevators which would need to clear the bottom of your robot if they were to hang beneath it. It will be tricky to say the least…
Is any offering of a “Buddy Bar” better than no offer? I would believe so.
That’s what a lot of people thought in 2010. However, few teams actually did, and AFAIK one was only ever used once. That said, the incentive to use one was very low, unlike this year.
Keep in mind that if you add a bar, you need to be sure your climber is strong enough to hang another robot plus some impulse force when latching. If using the bar breaks your climber, you just turned 30 points in to 0 plus a broken climber.
I would also add that if you fall you will be very unpopular with the team who’s robot you decimate below you.
With the right sensors and independently controlled winches instead of just the one we used on the Ri3D build. We think it is possible.
I definitely think if a team is going to try to build the “iron cross” that it needs to have some serious over-engineering. I definitely wouldn’t want to be the team responsible for dropping another team’s robot. We did serious stress analysis in Creo to determine if the idea was even viable before we ever cut a single piece of material.