My team and I are just putting ideas together. does anyone have any tips? Ideas? strategies?
so far, we have come up with a robot design that can hypothetically push another robot the direction that their wheels are facing and change the angle to make it harder to shoot. any advice?
Thanks! The limit height while deployed is 84" though. We’ll see what we could do 
Before you go nuts on torque for pushing, just make sure you can catch the people you are supposed to be defending.
Good Point! :yikes:
Honestly, if you make custom gearboxes that deliver enough torque, you don’t even need to make sure the robot you are pushing is moving in the same direction as its wheels. Easier said than done, however.
For most teams without reliable vision tracking, ramming into them should be enough.
why not just make a huge curved wall that extends up to block the robots view and have a ramming tool of some sorts
Consider putting all 6 CIMS on the drive or using the Vex Pro transmissions. This will let you be fast and pushy. Also, a 10 point hang is easy to make happen.
If you are on the side that you will be defending from, you are actually limited to 60 inches per G22 B.
a defensive bot needs the beefiest drivetrain and frame possible. it also needs to be quick, able to accelerate to its top speed in 1-2 robot lengths and traction. lots of traction.
Why build a defense bot when you can, with little effort, make a 10pt hanging, 1 point low goal scoring robot?
If you guys are planning to only play a defensive role in this year’s game, I urge you to reconsider. Scoring the smaller objectives, while not as glamorous as the larger ones, will still help your alliances win matches. Your season will be far more fulfilling as a result.
If you’re planning on doing all of this already and are just trying to find out about good ways to play defense, then don’t mind me.
An ideal defensive bot, besides playing good defense, should be able to score 2 discs (in the low goal) in auto (4 points). It should also be able to hang on the bottom rung for 10 points.
A defensive robot has two choices for playing defense, defending the opponents robots, or defending the discs. I believe that going after the discs is a much better option. To do this, a defensive robot should have a large shield that extends all the way to the height limit. Have this robot sit near your opponents feeder stations blocking both robots and discs from getting past. If a team can only get discs from the feeder station, you could be a great hindrance in their navigating the field.
You could also decide to go onto your opponents side of the field and sit in front of their goals to prevent teams from dumping. I like this a little less because some robots might shoot while touching the tower, making it difficult for you to slow them from shooting.
Honestly, I would just try to have a tall robot that can stop robots that can only get discs from the feeder stations. Blocking the transfer of discs from their feeder station to their goals is a good way to slow/stop an opposing alliance from scoring. With a defensive robot that can score 14 points too, you would be a strong 2nd pick at most, if not all regionals.
A good defense robot should be able to push opposing robots, but not be pushed itself.
A good defender should be able to take discs on its opponents side and shoot them to its team’s side of the field.
A good defender must have drivers that are aware of the penalties in the game, and they must be sure that they do not violate any rules.
This year, we were toying with the idea of using a high-airflow fan to deflect opposing shots, but we decided against playing defense. Due to the lower height limit while defending, some defenders might not be able to block shots, so a way to block the shots without being really tall may prove useful.
It helps for defenders to be able to maneuver quickly to prevent opposing robots to get around them, though having a high power drive base is the higher priority if you can only have one or the other.
Avoid at all costs getting penalties. If you’re playing defense it’s fine to be aggressive to a point but if I see your robot consistently being fouled you’re on the don’t pick list for us.
A robot drive system, a sturdy frame, high traction, and excellent drivers.
I strongly advise against a defensive robot for one reason:
Robots that are in contact with their pyramid can not be touched, whether climbing or just shooting
If you defend well, all they have to do is go to their pyramid to shoot
I’d hazard to predict that the best defensive bots will:
Weigh 120 pounds.
Have two speed transmissions.
Six or Eight wheel drive.
Good Drivers.
Four cim’s on drive (six cims stalling will throw your main breaker, I think)
Run every match.
WON’T GET PENALTIES.
Under 30 in tall (to fit under the pyramid)
Their defensive strategy would either involve the choke points located between the pyramid and the wall (to slow down traffic), or camping under the opponent’s pyramid and then running out to hit/ push them around when they try to score. You could also deny a climb this way.
Read Alec’s post again. Please consider not building a defensive robot. The low rung on the pyramid and the 1pt goal are there to give teams of all skill levels the ability to play an offensive game.
If your team has chosen to build a defensive robot, I suggest the following things:
What is so wrong with building a defensive robot? Seriously, at the rate some people in FIRST are starting to denigrate defense we might as well go back to 2001. If I was picking partners for a top team (and I never have, so maybe that’s why), I would be way more inclined to pick a good defensive robot over one that can maybe score a few points, and in almost any regional any team, regardless of “skill level”, can contribute to a strong alliance.
EDIT: This may not fall into the category of “need”, but I would consider some of the following non-traditional forms of defense:
A very large fan to blow frisbees offline - people keep talking about it, but this year with the extra CIMs and aerodynamically sensitive game pieces, I really think it can work!
A robot that quickly picks up and shoots frisbees away (not off the field!) to deny the opposing team from picking them up
Keep them from getting into their loading zone - yes, their are rules from touching another robot in its loading zone, but there is no rule preventing you from going in their loading zone, as long as you keep them out!
Be as tall as possible to block frisbees - if there are any long shooters at your regional, have some way to get 84" high to block all their shots
The robots they recommend building could easily fall back and play defense if necessary. A robot in a random qual with no standout opponents can’t play defense.
Also, a defender that can 10 point hang is far more valuable than one that can’t.