Any overunder robot/strategy ideas

It’s a great way to expand vertically, but the only problem is that there can be issues with structural stability since it will experience lots of torque. Worse, if you want to mount any type of grabber system to hang on the pole, it will be placed very high on your robot due to the nature of cascade lifts and you’ll take a hit in terms of elevation tier since it’s measured by the lowest point on your robot. Ideally, you want a lift system that will store your pole mount system as low as possible to maximize your elevation height.

At first, it doesn’t seem reasonable to drive over barriers, but it’s very much possible for another robot to push you onto the barriers in matchplay. So, you want to be able to drive off of them in any orientation because it can potentially cost you the match if you’re not able to drive over them.

If you could provide a sketch of your idea, that would be awesome.

The benefit of double zoning is that your scoring efficiency is (in theory) doubled and if other robots try to descore, there are two robots there to defend. Plus, even with change up style intakes, it can be tricky to descore from these goals.

I did the math for it and what’s interesting is that a 480 rpm drive on 4 inch wheels is actually faster than a 600rpm drive on 3.25 inch wheels. I wouldn’t recommend doing that since you’re taking a big hit with torque and with 4 motors, you run the risk of burning out your drive base super quickly.

I tried out cutting up a 3 inch flex wheel so that it has more bite on the triballs and that seemed to work.

I was thinking of a pushbot that can expand to the 36 x 36 inch expansion limit and just sit underneath the opponent goal. this ensures that your alliance never double zones and pretty much stops your opponents from scoring any triballs in their own goal. The only problem with this strategy is that your partners would be playing a 1v2 the whole match which can be extremely hard to win against good teams.

If you figure out a way to consistently get super high elevations consistently, then it’s worth it since your opponents will have to make up for a 4 triball deficit and even more if you find a way to carry another robot while you elevate.

You’ll see this used a lot in In the Zone. It’s a great lift system if you need to achieve high elevations and the biggest benefit is that it will lift perfectly vertically (ideally) and be able to lift very high. The drawbacks are that it’s heavy and takes up lots of space.

Purdue SIGBots (BLRS) has a guide online to all of the lift mechanisms along with details with how they work and their benefits and drawbacks compared to other designs. I would recommend using a 6 bar because it’s so compact in its stored position, but give that website a look to make a more informed decision.

Not gonna happen (I’m an adult mentor.) The drive/cata sharing should not be a big deal, since a slip gear cata only needs to spin one way to launch. Getting all 8 motors to lift would be trickier, involving cata and drive motors running in opposition maybe?

315G put out a nice explainer video on ratchets for their turning point season 315G's Turning Point Ratchets Explained - YouTube

You can see that any systems that only need to turn one direction to work can be shared on a single motor. With cata and elevation systems potentially only needing to turn one way, there could be an opportunity for motor sharing.


There really isn’t any benefit to double zoning, because in order to score, you need a robot to get tribals from the match loading area, which is on the other side of the field. That’s why the Purdue SIGBots and every over under reveal so-far have catapults in them, so that they can quickly and efficiently give tribals to their alliance partner to score, without double zoning and running the risk of losing some points

Not true


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I’m not sure if you understand how the expansion limit works. Unlike the 18x18x18 starting limit, the 36" image is a circle. Basically the farthest 2 points can not be farther away than 36". This is the same thing as during tipping point. 36-Inch Expansion Clarification. I am fairly certain this was covered somewhat recently in a related thread.

Actually, no. Your next sentence is correct - 36" max from one point of the robot to another.


How is that different from a 36” circle? If no part of the robot can be more than 36” from another part, that means it has to fit in a 36” circle.

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I believe lots of graphics in this post helps:


What if we use a (or two) double-acting pneumatic-piston for endgame. Recently I visited a first robotics team, and they showed me their robot from last year. For their endgame, they had to hang on monkey bars. They used pneumatic pistons to lift their robot up. I don’t know if the vex-legal pneumatics can lift the robots, but it’s definitely worth a shot, since we just came back from a season that was pneumatic heavy.

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