URGENT: Catapult Not Shooting with Enough Power

The catapult on our Pitching In robot isn’t working. It doesn’t have enough power when it shoots and my team can’t decipher the cause. It will only shoot a few inches in front of the robot. I have attached a video of the catapult’s issue in the Google link drive below. Does anyone have any ideas on how to fix our issue?


It seems to retract to soon after launching. Otherwise move the point of rotation around and add more rubber bands.

OK, so we need that side camera’s view. This video doesn’t show any information about your mechanism. We can see what the outcome looks like, but not the processes underlying it. Try to show both ends of the elastic that is being stretched, and the pivot points and gears involved.
I can make a general point that elaborates on @JcbMrgn 's description of it apparently stopping short. The launch platform hits whatever is stopping it. That bang and the vehicle shaking is energy being thrown away that needs to be given to the projectile. Let the launcher swing further. If you can design it right, the launcher (elastic extension and platform speed) will have given away most of the energy other than potential energy due to its height above its resting position.
Trebuchets do this by ensuring most of the final motion is in a very light swing, and hence relatively little kinetic energy still in the launch mechanism. In pelota, the ball is rolled along a surface at an increasing radius from the pivot created in the arm, and at a tightening tangent due to the curve in the basket, such that it tends to halt the arm and take all the energy away with it. How to play Basque pelota - Lonely Planet travel video - YouTube


Thanks for the quick reply, we were able to increase the catapults.

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