Types of Buddy Climbs This Year

FIRST General Forum
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#1

With robot reveals starting to come in, I have noticed that there have been three main types of buddy climbs.

  1. Under forks, This is where a team climbs, then drop a set of forks/sling and lift a bot underneath it. Example Team 2630’s “HawkEye”

Pros: There is nothing you have to attach to your alliance partner’s robot.
Cons: You have a height limit of the robots you can lift. You can only lift one robot.

  1. Buddy bar, With this type of buddy climb, teams will drop a bar(s) from there robot then attract hooks to there alliance. Then they will place the hooks over there bar and climb. Example Hyperion 3360 Hyperion’s “RECON”

Pros: It is the easiest to design and build. This design will allow you to lift two robots.
Cons: (You must attach hocks to your alliance partners, and if you get really unlucky with your inspector, you may get called for the cheesecake rule.) As @AndrewMcb and @wgorgen Pointed out this is unlickly, however you still have to attack the Hooks to the alliance partners bot and remove it which will would not have to do in style 1.

  1. Robot Wrangler, grabs another team with a Velcro (sorry hook and loop tape) strip that is attached to the other team’s robot. Examples most famously 148’s 2018 robot Uppercut. This season 1678’s 2020 robot and 3539’s 2020 robot.

Pros: It is relatively essay to line up on, and a bot doesn’t have to be exact align as it will be intake in.
Cons: (Again, if you get unlucky with your inspector, you may be called for the cheesecake rule.) As @AndrewMcb and @wgorgen Pointed out this is unlickly, however you still have to attack the Velcro to the alliance partners bot and remove it,which will would not have to do in style 1.

What are your guy’s options on the three buddy climbs, and will we see others? Which do you think will be most common or effective?

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#2

I doubt that this (attaching a piece of Velcro) will be ruled illegal by any inspector. One of the earlier team updates explicitly made this type of buddy climb legal.

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#3

For reference, that was Team Update 2 - It added to the cheesecake rule “without the assistance of another robot” and also defined what a major mechanism was in the glossary. This minor change still makes the cheesecaking that was done in 2015 for Can Wars illegal, but made buddy climbs legal.

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#4

Relative to type #1, we made the determination that the height limit was a tolerable constraint. Tall robots would probably be able to climb on their own. Short robots would be designing to go under the wheel of fortune, so they should be able to limit their height to 28" in some configuration. So, the design constraint for the buddy lift was to be able to fit a 28" tall buddy robot between the forks and the bottom of the robot.

I think we will see that this is the dominant mode for the buddy lift. We have seen one successful demonstration (2630) and I believe this is also the design that Spectrum is going for.

As I stated in the other thread, the pros of a single buddy lift are that you can get the ranking point with very little help from your alliance partners during qual and you are able to get the extra climb points during elims even if the third robot on your alliance cannot climb (the assumption being that your first pick will be able to climb).

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#5

Type 1 does seem the most reliable, but it does present some obvious and not so obvious problems. The obvious is the height limit, which may or may not be a problem depending on alliance partners. If you’re in an alliance with two tall bots, it’s essentially useless. As long as you have a low bot (and those are less, but by no means unlikely, to climb on their own) then you’re good to go. The less obvious problem I can see with type 1 is the time it will take to work in actual match play. The system requires that you position and climb, then deploy your buddy system (forks, platform, etc.), then have your partner align on that system, then raise them. Unless you have a good bit of practice with your partner, it may be too complicated to work quickly. We saw this with buddy lifts in Powerup, where the system worked, but aligning often took too long to be successful (and that was with the main climber waiting for the buddy but both ascending at the same time, not sequentially.) This will obviously be less of a concern during elims, when partners can practice and repeat the sequence.

Type 2 is certainly workable, but does present many of the same balance problems that multiple individual climbs do if the bars are on the sides (which is easier to do than on front and back due to other mechanisms.) It will be critical to their success to have the system as resistant as possible to changes in CoG caused by lifting another robot(s). Since it’s relatively easy to do, it will certainly be the most common type. And, as noted above, you do run the risk of some inspectors rejecting things like added hooks, plus even if they pass it requires re-inspection and re-weighing of your partner robots every time you add or remove these mechanisms.

The type 3 mechanism is interesting, but I can see a lot going wrong with that one. Like type 1, it is limited to a single buddy. The balance problem is not too much of a concern, since it’s likely to be attached to the rear (or maybe even the front) of the robot, but a stable system like 1678’s is still a good idea. The real problem I see is in the attachment and grabbing of the velcro. Any failure there leads to dropping your buddy across your own lifting forks, which likely won’t go well for them and possibly not for you either. It’s the cleverest system, but I think the hardest to implement properly.

I still contend that we’ll see relatively few successful (or at least consistently successful) buddy climbs this year compared with the past two. They would be more common at higher levels of play (DCMPs, Worlds) but the likelihood of all robots on an alliance being able to climb on their own also increases in those situations, so the need or desire for the buddy climb decreases. We’re planning to be proactive with working out balance solutions with our alliance partners instead of constructing a buddy lift system, since that can be applied to any other climbing robot regardless of height, weight, or configuration. It’s all math, after all.

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#6

Don’t see why it’s much to worry about - nearly every team in FRC depended on this in 2017 and it seemed to work fine.

#7

In 2017 this did become a issue for us (partly do to we were down to one rope at champs) but the loop side will wear overtime and become strings over straight loops. But if it is maintained probably then they should be okay.

#8

And robots regularly crashed to the ground using this in 2017 too. It’s not that it won’t work, but the problem isn’t trivial, since failure can have unfortunate consequences.

#9

What kind of loop tape were you using? We stuck 1 layer of loop on our climber and never had to replace it at all.

#10

Loop was on the rope and I do not remember the brand of tape but it do remember that it was something descent (not dollar store) and we used the matching hook on our drum.

#11

There’s something I think that’s missed here. Short robots are more likely to be advanced teams if this is the design intent. Less experienced teams don’t add the constraint of driving under the color wheel. That means you’re basing your strategy on catering to teams that are more likely to have the experienced needed to climb making them a bad fit for the buddy climb target. Those you’re most likely needing to help are the taller bots that are built by inexperienced teams and didn’t quite complete the climbing mechanism.

#12

This is wishful thinking.

Less experienced teams shouldn’t add the constraint of driving under the color wheel. There’s a catch-22 involved here though, because a more experienced team would understand the tradeoffs involved and make a well thought out decision about whether or not it’s worth it to go short. Lots and lots of inexperienced teams will go short this year when they really shouldn’t have.

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#13

That has not necessarily been our experience in our district events. We see a lot of teams designing short robots that are only capable of performing a couple of tasks, or that focus only on being able to play defense. Historically, we will have a couple of teams at each event that will only have a KOP drivebase and nothing attached to it.

You are correct that there are a number of experienced teams that will build short robots. But we believe that there will also be a number of less experienced teams that will not even attempt to build a shooter and will merely collect balls from the loading station and dump them into the low goal with a very simple bucket type mechanism. In order to make their life easier moving back and forth across the field, we believe they will stay under 28" so that they can use the trench if they want to.

Bottom line is that we believe that many tall robots will be able to climb. Short robots will have a harder time designing a climbing mechanism and many teams that design a short robot will not have a climber. If another robot is able to climb, we won’t need to use the buddy lift, and we believe that there will be a lot more short robots that cannot climb than tall robots that cannot climb.

We could be wrong. We will see this weekend when we get our first real look at NC teams…

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#14

I’m hoping it works out for you because that’s a beautiful machine.

I’d agree there will be a number of bots that struggle to complete a bot and those will show up, likely short. But, I’d expect that’s also a smaller number than the total amount of bots that make an attempt to design and come up short.

That leads to the following:

Less experienced teams aren’t likely to try to build a short robot that climbs. That means you’re putting yourself into believing one of two things is true:

  1. A non-trivial number of inexperienced teams will try to build a short robot that climbs
  2. A non-trivial number of inexperienced teams will choose to go after a trench run instead of a climb

If those aren’t true, it’s not so much wishful thinking as playing to the odds. I’m leaning towards expecting more of those teams will try for the taller climbing bot than go for a short bot.

As always, either of us could be wrong here. We’ll see how the game plays out.