Rubber band attachment for throwing a ball from base - FLL 2012 Bowling Pro Preview

Sometimes you could just throw a ball from base and solve a competition. Or at least many teams think so. In this video we would explore a very simple attachment for throwing balls from base. Can you use this for other missions? - we think so. Check out the video. 

  • #118
  • 01 Dec 2015
  • 3:39

Catapult over the brick

Building instructions for the catapult that could be placed over the LEGO Mindstorms EV3 Brick. The idea of the catapult it to throw objects. The fact that it is over the brick makes it very convenient to place the motors below the brick and to use the Catapult. 

This robot construction itself was used in the FIRST LEGO League Senior Solutions competition


The Idea

Many times you just have to throw something, or it's a good idea to throw something from the base, so that it could reach the mission, and solve mission from the base. You won't lose any points, and it will be quite fast and today we are showing such mechanisms. So we are solving the April 2012, Senior Solution Mission where we had to throw the ball from somewhere on the map, and then reach these parts and get them on the field. That was our mission, but we are solving it by throwing throwing the ball from the base.

The Solution

We've prepared an attachment that uses rubber bands. This here is the attachment. You can just zoom out so that you can see more clearly. Now this here is the attachment and it has two rubber bands and when I release the attachment, it fires. And it could fire a bow, it could fire other parts, so it's quite straightforward.

But it's interesting in a number of ways. First, it's a pinless attachment. So, as you can see it's quite fast to move this attachment and place it on the robot. So it's just...sorry, too much firing and it's deconstructed. Again, you just place the attachment on the robot. And that's it. Then we must trigger the firing because we can do it by hand and we pivot the model. Now if I load with the model we are holding the attachment, and while holding the attachment we can move on the field or we can even fire from base. It depends only on the configuration of the rubber bands. And when we decide, we release the model, and we fire.

It's important to notice that the EV3 model, the EV3 competition robot from video 58 could be extended right here on both of its sides so that we can add pin-less attachments to it like this. So it's quite fast. Just add the attachment, no pins involved, and we can then solve different missions with this attachment. Then we load. We move on the field, or even from base. We release, and we fire the ball.

Let's now try to fire the ball from the other side of the table and it should reach me and get these parts on the field. Now if we start the model from the other side of the table, it will throw the ball to these parts here. Like this. And you can always use this attachment to throw something from the field or from the base.

Building Instructions

You can find the instructions for building this attachment below the video.