What characteristics are necessary for a defensive robot?

(Following the suggestion of Jij, I’m copying the post I figure would make sense to start this topic so as not to derail Daniel’s thread)

I really wasn’t going to get into this. But you’re pushing this as a concept, so now I have to explain why it’s flawed.

Say that, hypothetically, you could deploy this robot during the first 0.1 seconds of Autonomous. The cylinders are locked down entirely, unless you want to open them. I can tell you right now how even a semi-decent alliance could beat it.

Red Robot 1 plays defense on your partner. For the entire match, all he does is push and shove your partner. He doesn’t have to pin your partner, just hit him repeatedly. He has two goals. The primary goal is to stop your partner from scoring in the cylinder. We blocked off an entire trough last year with a 6 motor pushbot. Preventing access to one 8" tube is easy in comparison. His other goal is just to slow down your partner’s ability to move game objects into the end zone.

Red Robot 2 moves game objects into the end zone. He completely ignores the cylinders. Move their objects in, take any objects your partner has introduced out. He’s uninhibited. He has the entire field and all the game objects to use. You aren’t stopping him. Your partner sure isn’t. In 2 minutes, he could easily score all 40 points.

We spent a long, LONG time trying to work out what makes a defensive robot feasible this year. These were the three criteria we came up with.

  1. The robot must be able to block off both cylinders from the opponents. This MUST occur during the Autonomous period, and hopefully it takes place in the first 5 seconds of Autonomous.

  2. The robot must be able to prevent the opponents from playing defense on their partner. Otherwise, we get the scenario I outlined above and you loose.

  3. The robot must be able to prevent the opponents from hanging. We saw a double high-hang posted to the forums earlier today. That’s 40 points. That’s way too much to be an acceptable weakness.

I’m sure there are other people who have looked at the problem, and I welcome your input. If you could do the first two of the three things I described, I think that could be a very solid defensive robot. But doing just one of the three seems like it will be ultimately ineffective.

This is my version of a cautionary tale to anyone thinking “My design isn’t working. I’ll just build this and win.” Don’t. Stick with what you’ve been using all season long and keep improving it. You’ll have much more success.

A bit of a radical strategy we experienced last weekend was a 10 motor 2:1 speed drive annoy-the-living-****-out-of-the-opponent bot. It was deadly effective at disrupting nearly all stash attempts by the enemy.

Building off of this, I guess I should suggest some other ideas that we kicked around as needing to be possible for a Defensive Robot to do well in a competition.

  1. Scoring Buckyballs in the Cylinder once they’re in the end zone

  2. Scoring Large Balls on the Cylinders once they’re in the end zone

  3. Scoring Buckyballs in the Cylinder from across the field

  4. Scoring Large Balls on the Cylinders from across the field

  5. Moving Buckyballs in and out of the end zone

  6. Moving Large Balls in and out of the end zone

  7. A way to prevent hanging in the first 15 seconds of the match, making anyone who doesn’t hang in Autonomous unable to do so, and those who do hang during Autonomous unable to come down and participate in the match

  8. Descoring Buckyballs from the cylinder

  9. Having an alternate configuration in order to accomplish different tasks based on the match at hand

Anyone have other ideas? Opinions? Or does no one care, because Defense is nearly impossible in Toss Up?

I think a descoring robot with a bib ball launcher could be deadly effective a worlds where your partner can handle filling up your own tube and score for you after you took the opponents stashed balls out.

Another idea that I have thought of is a robot that high hangs with a ball in Aton and then unfolds and holds all four large balls (you alliance giving them to you)

but all of the ideas I have come up with this year have relied of a good robot to, as Space would say, the rest.

That’s all.

You only get the points for one large ball. Your robot is essentially worth 30 points, from the hang and Auto.

ahh, but the other team doesn’t have them. (I meant the opponent’s large balls)

To clarify further. At the end of the match you would be carrying one of your balls and all four of the opponent’s large balls. five in all.

So, I have been considering a defensive robot and one of the most beneficial ones I can think of is a combination of several I have seen on the forums. The OP of the other thread set up an expanding wallbot in front of the goals. I feel it would be a great strategy to do this in front of the 12" barrier during autonomous. Make it a little longer than their original bot and only let your alliance partner into the goal zone and keep the opponent out of there completely. That gets rid of any opportunity for the team to score Bucky balls in the goal and if done well, keeps opponents from dropping any balls into the goal zone. If this is completed, then set up a blocking mechanism that could block pneumaticly fired big balls. Finally, have an arm similar to the “Cap bot” I saw earlier that can maneuver big and small balls quickly and efficiently over the barrier. It would be crucial to have the arms geared for speed but they should be strong enough to pick up the big balls easily. Ideally, your partner would be on the other side of the barrier and you could simply feed balls to them from the middle zone for them to do things with. This robot could effectively limit the opposing team to hanging, which at most could be 20 points and a few single points from the middle section. I don’t feel there is a legal way to take away hanging from a team but this takes away almost any other form of scoring.

A popular tactic I have seen (and our team used for a while before we built our latest iteration) is to herd all of the opposing team’s Buckies into the hanging zone. We encountered a robot that could pretty much just hang and nothing else, and we were able to trip it up (Sometimes, literally :smiley: ) since it could not pick up buckies. Although it might seem counter-intuitive depending on a team’s method of game object manipulation, herding Large Balls into the hanging bar area before the last 30 seconds of a match could be quite effective too. Our double-hang sometimes got messed up by this tactic.

Oh that’s an interesting thought. So then to apply this to the bot I suggested, maybe having something you can place a big ball on on your wallbot that works as a catapult for the big balls would be effective. Have it on a turret or just have it set up so you face one corner and are able to throw the big balls over.

so I re-read the title and realized that this thread is not about what strategy to execute, but what is required to do so effectively.

A defensive robot should be hard to stop.
I have seen a lot of defensive robots fail because someone spread the word about how to stop it (ya, I do think that’s rude). the ideal defensive robot can execute it strategy regardless of any counter-measures.

A defensive robot should still let the score of the match be high it that is desired.

another thing to consider. the best defensive robots not only play the robot, but the robot’s driver as well. I remember watching exothermic’s troll-bot trapping us into the isolation zone while pushing our dead alliance partner along with them during worlds, just a vividly as watching Josh Wade do his thing a nationals.

To win, a defensive robot must be:

  1. Reliable and well built.
  2. Able to get into place before the opponent can hinder it.
  3. Able to protect its ally from defense OR cancel out that defense by scoring or descoring.
  4. Able to have such a heavy effect on the metagame that it is almost mathematically unbeatable if it and its partner work properly.
  5. Secret enough to leave the opponent little or no time to strategize against it, yet not so secret that no teams know to pick it in the elimination matches; AND/OR able to rank high enough to be a picking team and pick a good partner.

Just my thoughts, feel free to add on.