HELP! Ball wont shoot out the top of snail bot

My team actually had the same issue. I have written about this before, but anyway, after trying several different angles, one of my teammates discovered that by using rubber bands to force the hood down, we were able to shoot the balls into any of the 9 goals. The downward pressure coming from the hood with the rubber bands helps push the balls out.

I posted the video on the forum before, but here is the video again.

If you watch the video, after the ball is shot into the goal, you can see the rubberband at work, forcing the hood downwards, once the ball is shot out.

From what I see that angle is way too steep. If you could make it less of a steep angle it was add compression along with a better launch angle. I would also recommend maybe trying a curved hood out of lexan. I used that this season and it works out well. I will give you the link to my google photos and if you look more torwards the bottom you can find some up close pictures. Just keep in mind it really doesn’t have a be a strong curve. We only had it small one and it worked great.


Bit of a late reply, but shooting this year is based of compression. I would try different angles and maybe a flat hood thay doesn’t force the ball down once it’s shot out. It seems that If you adjust it lower, it’ll shoot far to low to go into the goal. Having a flatter hood and a backboard may be the move here, however tuning backboard can be a slight issue if done incorrectly.

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(sorry kind of late but) We had the setup you see where the hood is pushing the ball down in to the goal, we took this bot to our first tournament and did pretty poorly because we could not score in middle goals. But Its cool you found a way for it to work. How did you score from farther away? We had to be basically hugging the goal for it to work.

Oh, we couldn’t really score for far away, probably the farthest the ball was able to shoot was around 3-5 inches from the goal. Most of the time, the robot hugged the goal.

There really isn’t a reason to score from afar. You should also be consistent on the distance so the your shots can travel the least amount of distance. If you watch some of the videos on the google photos it will show the amount the ball travels which is pretty small

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My team has our top roller with its own motor to give it the most power possible. (We don’t have a sorter) Our top roller spins at 1200 rpm and we had to build a backboard because we could shoot from too far away. The robot shooting the ball out without the backboard would fly roughly 10 feet to the ground, far exceeding our needs. Having our own backboard means we have excess power which is convenient because it reduces error.

I would suggest making a cured hood out of polycarbonate (Lexan) such that the hood’s path is more or less concentric to the top roller.

On the matter of fitting it in size: My team has the hood mounted to standoffs which connect it to a pivot near the top roller’s center. We fold it up by “nesting” it inside the robot where the balls travel up. To be honest, that is overkill and one of our sister teams has a very simple hood: They have a flag from turning point bent into a curve between two pieces of C channel separated by standoffs. Their hood is incredibly simple and small but not always the most robust. Sorry if I described this poorly, I would be happy to offer more details and pictures if anyone wants.


Yes, could you please provide more details and pictures. I am amazed on how you can have 2 much power!

We couldnt even shoot from 3 inches away.

What is the RPM of your flywheel/upper roller? My team’s flywheel spins at 600 RPM, and that is sufficient enough to score, even at a 3-inch distance.

We were at 600 rpm as well. I would show pictures but I dont have any that dont include me or one of my teamates.

Our problem was because the middle goals are only connected to the barrier at the back we were pushing it up making our ball have to travel further and It would hit the rim and bounce back.

This may sound a little weird, but if you have a motor to spare, you could make a hood roller that compresses and shoots the ball out. We did that and it worked really well, although taking up a motor

Even though my team’s robot is complete and well-running, I am actually curious about doing that. Do you have a picture of the motor hood roller concept you were talking about?

Disassembled it :confused: but I think I have a pic

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looks kinda like this robot:

Thanks, I am gonna go try making one now

In my opinion that would be a complete waste of a good motor. There are a ton of ways to make great hoods as long as you put a little effort along with tuning if you want to get into that. There are a ton of videos and pictures of robots with good hoods that will offer a lot of better options.

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Yeah, honestly upping the rpm on the top most roller really helped. We did 30:6 and we got 1000rpm with the top roller. We were also able to figure out that a hood with grip tape on it does not work at all. It just doesn’t allow the ball to have as much speed and keeps it down. Also, if you can, make the hood out of poly carb as it will give it that flex that the ball could use to score. This is just my two cents, but it was useful to us, so maybe it’ll be useful to you guys.PXL_20210506_233026422