Separating stars

In a few of the previous matches, stars were sometimes clumped together, which could be difficult for single-star catapults to intake & shoot. Does anyone have good ways for separating the stars?

Our team is looking to take advantage of clumps as is, but we had an idea for “declumping”.

Essentially, all you need is an extra C channel sticking out parallel to the ground at a height of roughly 8". Angle the front to something like a “spearhead”, and then when you push this through a clump of stars it will separate the stars. If you attach this to your catapult, you can then do a quick launch to scatter all the stars, making it easy to intake and launch.

I don’t really get it… is it supposed to separate stars that are kind of on top of each other?

Yeah, looking back at my original post it probably wasn’t super-clear what I was trying to say, sorry :stuck_out_tongue:

The idea is to get into the C channel into the middle of the clump, and then launch the catapult once. Because of the concave shape of the stars, even if the C channel goes straight up, all the stars end up rolling backwards, separating the clump. This would make it easy for a one star catapult to now intake and launch for real.

I’ve attached a crude drawing but hopefully it will make what I am saying clearer. As the C channel goes up, the star rolls away to the side. I only drew one star to keep it simple, but the same would happen to any other stars in the clump.

I get it now, but it might be better if there was a way to separate stars without launching.

what if you just run into them?
or better yet bulde a lancher to launch the hole clump at once?

I don’t think running into them would separate them.
If you built a launcher to launch a whole clump, then you wouldn’t be able to launch less stars without them getting out of the field.

I respectfully disagree. Our launcher has basically analog launching distance, so we can shoot 3 stars from far zone to far zone and 1 star to near zone, and everywhere in between. Obviously, we’re not using a conventional design (all hail dumpapult!) but it is possible to have a launcher that launches both clumps and fewer stars.

What about teams that will use a conventional design (probably us)?

In that case, I would recommend using distance to your advantage. IE, you can launch a clump from right next to the fence, or a single star from the field perimeter. That should be enough of a difference with the same tuning of rubber bands.

You can also angle your shot to increase the distance you can shoot, up to about 17-18 ft (12 * sqrt(2) ft). That’s an option.

I forgot about that, that’s a great point. Probably the biggest thing you would have to watch out for is ensuring that your trajectory is s/t stars/cubes won’t clip the fence as you launch different weights from different positions.

Does that use a lift?

Probably ought to make sure we’re all on the same page as to what you mean by “lift” :stuck_out_tongue:

If you mean lift as in 4-bar/6-bar, nope, our catapult is very similar to what some people call a “2 bar” (think kinda like VEX clawbot), except we don’t power the catapult by turning a gear attached to the metal.

If you mean lift as in hang mechanism, we decided to remove our mech for this competition because it was skills only, and we reasoned that the 1.6x speed boost we could get by switching internal gearing (not possible with hang mech) was worth it.

Our team is doing pretty well so far after our day 1 at the competition (seeded 3rd in programming, driver, and combined robot; pretty good for a team that doesn’t have a field yet XD). Assuming we have the time next week, which is right before our school starts, we might shoot a reveal video, but hopefully at the very least we will illustrate how the dumpapult functions with pictures and/or raw footage.

I did mean 4bar/6bar as lift. Do you think that a piece of plastic in a steel frame wold work for a catapult? I wold like to lonche a cube from far zone to far zone. If I can, I wold like to not use a 2 bar.