FLL 2020: How to accomplish the Bench mission with LEGO Mindstorms Robot Inventor Pro Preview

The bench mission was one of the most difficult we've encountered, especially when it comes to accomplishing the mission reliably. The goal of the mission is to push the bench down, lift part of it and leave 4 boxes at specific places. The whole concept of the mission is awesome. Here is how we did it:

  • #1845
  • 23 Dec 2021

There is an interesting concept when it comes to unlocking - you move forward with the attachment, the boxes are locked and them you push on the mission model this unlocks the attachment and the boxes fall into places. It seems fragile and it kind of it, but you will see how we manage to make it durable enough for a competition ad FIRST LEGO League.


This video tutorial is about the bench mission, and the bench mission was one of the complex missions in the FIRST LEGO League 2020 competition. The goal of the mission, it has two goals. First, you have to somehow lower the bench, and then you have to place these green boxes, four of these green boxes on four different places. So the whole attachment should do two things actually. It should lower the bench, place the four boxes, and then return part of the bench back to base. So actually three things, and it's quite complex to get your head around. Let's see how we accomplish the mission. Move forward, pull, and then drop.

This time here, it didn't work. We didn't get all of the boxes in the concrete places. We have to drop them specifically in the areas on the field. Second time, move forward, push with the lever, move forward, return. We return with part of the bench back to base. This attachment is our third or fourth or fifth try of how we can accomplish this mission and at the end it got really simple. So as you can see, it's quite easy even with one hand to place this attachment on the robot. And it is really interesting how this attachment works. Here is a close view of this attachment. You can see that there is a locking mechanism that prevents the boxes from falling through the holes. And when you rotate, you free, unlock and the box falls. And now if we place four of them on the attachment, they are locked in place. You can move with the attachment. The attachment is on the robot, you move with it. And when you decide you use one of the motors, push on the lever, unlock the attachment and all the boxes are now in place. Very simple idea, very powerful idea, and it works quite well.

See you in the 10 out of 10 tutorial.

Courses and lessons with this Tutorial

This Tutorial is used in the following courses and lessons

Image for FIRST LEGO League 2020-2021 RePlay Solutions and review with Robot Inventor
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Image for M04. Bench
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