Team 42700B/C 2018 Winter Reveal "lobsterBot"

Please give me feedback on the video and bot. We are currently working on the next iteration of the bot, so feel free to ask questions about it. The video description gives more information about our bot, which competitions we attended, and what we are planning for the future, as well as an event that Saint Louis School is presenting next year.

What is the motor layout?

four high speed V5 on drive, one high torque on catapult, one high speed for the descoring bar, and one turbo for the intake. The intake motor is placed on the left rear of the bot. The drive motors are direct to the front and middle, and the rear wheel is chained to the middle wheel. The catapult motor is on the right side of the bot and uses high strength axles. The descoring bar motor is placed up on the front posts.

In the future one of the design considerations we are keeping in mind with our owlBot is having a lower center of gravity, which will be reflected in the way we place our motors on later bots.

E: Left front is on port 1, left back on port 2, right front on port 3, right back on port 4. Catapult is on port 5, intake is on port 6, descoring bar is on port 7.

Drive has four 2.75" omni wheels contacting the floor, and two raised 2.75" traction wheels for climbing.

E2: It’s getting a little too far past my bed time, thank you for the questions : ') I’ll answer as many as possible tommorow.

Very nice robot. Did you ever have any trouble with refs about pushing people off of the center platform?

Lol. I asked the same question the first time I saw the vid.

To clarify, you said that you have a 15:1 intake? Or did you chain it down outside of the gearbox?

That’s a pretty unique catapult design, the arm is fairly compact given it’s size. Any plans on upgrading it to shoot two balls at the same time?

No. I was explicitly told I was good to go as far as pushing people off of the top.

???Bot will be a 2bc. I’m planning to build a whole new robot with vastly improved subsystems - the pinnacle of my freshman year.

E: I could probably take what I have now and make it a 2bc - if I have time before states I will.

I believe the intake is 18:1, and is geared down outside of the gearbox by chains.

You know how to get ahold of me if you need any help with that. @Xenon may be a good person to talk to as well. (lol, stuck him out on a limb there)

So, the intake is 18:1 or the gearbox is 18:1?

the gearbox is 6:1, and the intake is 6:1 through the use of a chain. Sorry for the incorrect information, I am a little tired.

E: it’s 6:1, forgot that I was too lazy to swap out the sprocket attached to the gearbox and just swapped the intake sprocket for a bigger one after it had too little torque.

Looks really fast for 6:1 total. Are you using 600rpm cartridges? Or just the standard 200 rpm?

The 600rpm cartridges. I used a low quality phone camera to record the close ups, which is probably why it looks faster than it is

That’s still pretty fast. 3600 rpm, right?
I also really like the catapult accuracy. It’ll be harder to do that with a 2BC. How do you plan to change your strategy to adapt?

I think it maxes out at 600rpm, because the turbo motor is 1:1 with the intake sprockets.

Probably strengthen our drive so we can’t be pushed around as much, as well as play much less defensively to focus on those important double shots. I’m thinking about how i am going to load the catapult, and in my mind it should function the same as the one ball catapult.

I’ll probably focus a lot more on the build quality and wiggle of the catapult for the two ball catapult. meaning no more zip ties.


Sounds pretty sweet. Do you have any plans to change your loading mechanism?

not really. I’m currently able to store a ball in the conveyor itself, and it functions well. I might want to load the two-ball catapult side on, however, if I can’t find a way to do it vertically. For owlBot it remains the same unless I decide to go 2bc.

I’ll work on sending you what I did. It works pretty well. I don’t really recommend side loading.

hehe not really lol.
my catapult is pretty crummy, I need to do a rebuild

Someone mentioned 2-ball catapult…?