Automatic or Manual flywheel shoot? Curving problems?

Should I make a single button that automatically spins the flywheel, waits for it get to max speed, then indexes all the discs, or should I make two separate buttons, one for flywheel, and one for indexer for manual shooting?

If automatic, all I need to do is get 3 discs stacked in my robot, ready to shoot, and just press a button, but I won’t be able to shoot one at a time, and if I only have one disc, the code will still run as if there were 3 discs. And if the angle is wrong, then I would miss all 3 discs.

If manual, I can shoot however many discs I want and if I accidentally miss one, I can readjust the angle, but it might be harder to press two buttons at a specific time and at the right time(might press indexer too early/late- wastes points/time).

I don’t really know which is better, so which method should I do, or should I do both?

Also, how would I reduce the curve of the disc when it shoots out of the flywheel? Does it have to do with how much the disc compresses, or how long the piece of metal the disc is being pressed on(sketch below)? I’m also using a 2 motor 1 wheel flywheel.

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I would advise designing your robot to be able to intake discs while keeping the flywheel on. Because of the rotational inertia of the flywheel, the motor takes less energy to keep the flywheel spinning than to start it up from nothing. As for your button mapping, I would have one of the shoulder buttons switch the flywheel speed between a slower speed (for close shots/overfill) and a higher speed (for long shots/awkward shooting positions). Have it so that if your indexer button is pressed once it fires once and if its held down it fires 3 times in rapid succession.

I assume you have either a motorized or pneumatic angle changer. Have a button that switches between an up angle and down angle (for pneumatic angle changer) and automatically sets the rpm of the flywheel to slow when up and fast when down. A motorized angle changer is a bit trickier to code as you should incorporate preset values that follow the button mapping above but to take advantage of using a motor to change angle you should also include a manual angle changing mode either with 2 buttons or a joystick. For specific buttons ask your driver what they prefer as they will be the ones using them.

For seeing the effects on the disc as a result of changing the length of how long the piece of metal the disc is being pressed on you should test it yourself and record the data in your notebook (looks very good for judges :)) You are aiming for a soft gentle shot that has as little rpm drop as possible to maximize overfill capabilities and maximum rate of fire.

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Build a test rig that is easy to modify between those and maybe other options, design experiments, write them up in your notebook and gain valuable practice at being an engineer :).

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But if you keep the flywheel on for the whole duration of the match, won’t the motors burn out? And since I’m using 2 motors for 1 flywheel, shouldn’t this not matter too much?

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Yes, 2 motors will burn out less but if your friction is low, the motors can handle spinning the flywheel the whole match. Our 1 motor flywheel gets very hot at around the 3:30 mark.

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So you’re saying that leaving the flywheel running the entire game is better?

If your driver is skilled enough to make sure that the flywheel is at full speed before you get to your shooting position you don’t have to have it on the entire game. But that is a lot for your driver to keep track of when they should be purely focusing on cycle time, aiming, and evading defenders. You could also implement sensors to achieve this task or just leave the flywheel on the entire game.

Our team, 2990E, leaves our flywheel on the entire match. However, our idle speed is very different from our ranged shooting speed. We have a no-cart flywheel on bearings, so our friction is very limited, and we haven’t ever had challenges with the motor overheating, even though it is set up in a hot swap configuration. We use a 3in flex wheels as our flywheel, so we have to spin it up slightly faster than a 4in, but it hasn’t been a problem at all so far. Our close range shot runs at about 1/3 total power, so that’s where we idle. We use a voltage controller for it, so battery rundown isn’t a big issue, and we don’t even come close to using all of our available power in a match.

Tldr; Yes. I think running the flywheel at reduced speed the entire match is a good idea if you can pull it off without losing power or overheating. Hope this helps!

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