Video tutorials -

• FIRST LEGO League

-

• Gears

Here is our solution for preventing torsion and bending of the LEGO Mindstorms EV3 axles.

How to align the wheels and how much should you push for this solution?

There were a few problems with the 40 teeth gears that we were using. Let's list some of them

The M08. AEROBIC EXERCISE is one of the very common types of mission in FIRST LEGO League robotics competitions. I think this pattern of missions was first introduced with the growing abilities of the participating students that were constantly reaching the maximum number of points. So the competition introduced mission that require a lot of time - 20-30 seconds, are time consuming and are complex. They requires a lot of moves. This here is a video tutorial on how it could be accomplished

In this tutorial, we add another mission to our current program. This mission is - hanging the Gecko from the FIRST LEGO League Animal Allies. 

We calculate the number of rotatios when a gear system is involved. The driving wheel will have to do a number of rotations for the driven wheel to rotate to a desired number of degrees. In our specific case when the driven gear wheel is rotate to about 90 degrees the legs will lift the robot.

This is a teacher's note about the math behind calculating gear ratios with for our lifting attachment. It math model we build in previous tutorials is not exactly correct and here is the explanation why.

The task in this tutorial is to execute the program 10 times and to do it yourself. If you have your attachment then use it. If you have our attachment then use it. But execute the program 10 times and make sure that it works. 

Sometimes the answer that you get by calculating seems not to be right. Is it the calculation that is wrong. Probably it is not the calculation, but something is happening with the robot. 

This is a 10 out of 10 video tutorial that demonstrates the consistency and reliability of the robot that accomplishes the Unlock Cargo Plane mission. The attachment is an active attachment with gear wheels. It has a single lever constructed from 2 beans and we use this attachment to push on the mission model.

Calculate the number of rotations you have to do with the motor to rotate the final small 8 teeth driving gear wheel to 1.25 rotations?

What should you as a teacher know when the students are trying to achieve a program and robot attachment that could reproduce their behaviour 9 out of 10 times. 

If you've done the calculation following the previous tutorials you would arrive at a result of 18.75 rotations. But this is not the correct answer. The calculation is wrong, because the math model that we've built, although kind of obvious, is not correct. When experimenting the correct number of rotations would be 37.5. This is a large difference. Two times larger. Exactly two times large. Something should be happening here - and this thing is "planetary mechanism"

This is a 10 out of 10 tutorial, demonstrating the consistency and reliability of the active attachment for switching the engine in this mission. The power is transferred through a system of gear wheels to a lever at the end. We presume that the robot is already positioned.

In this video tutorial, we demonstrate how to release the cargo of a mission model. This mission model is an Airplane. We have to push a lever down to release it. We use an active attachment with a gear wheel.

What should you do as a teacher when the students are calculating the gear ratios and number of needed rotations?

In this video tutorial we accomplish the basketball mission from the FIRST LEGO League 2020 reply competition. We use the LEGO Education SPIKE Prime competition robot called Gazon. You will learn the principles of accomplishing a mission of two parts - put the ball in the basket and lift the basket.

In this LEGO robotics video tutorial we will accomplish mission 8 from the FIRST LEGO League 2020 RePlay competition. The name of the mission is Boccia. What you will learn from the video is how to accomplish complex missions that require following a line, aligning to the line and accomplishing many mission models in a single run

In the previous video, we found the correct answer for our task and it is 18.75, or is it?

In this video tutorial we accomplish the Basketball mission 10 out of 10 times. We use one of the more complex attachments for the FIRST LEGO League 2020 RePlay competition. You will see an learn how to successfully and consistently complete a mission that requires the robot to put a ball into a basket and lift the basket, or lift the basket and put the ball into it.

This video tutorial demonstrates an attachment that flips a mission model. The mission model is attached to the field, but it contains a lever. This lever must be flipped from one side to the other. There is a switch. We use a pinless active attachment with gear wheels, and you can see how this works in the tutorial. There is no use of sensors as we don't need them. We will leave the alignment and positioning for some other tutorials.

This LEGO robotics video tutorial is a 10 out of 10 run of the one of the most complex missions at the FIRST LEGO League 2021 RePlay competition. As the mission has three parts we are measuring the success rate of each part of the mission. What you can learn from this tutorial is how to achieve three missions in a single run including line following and a lot of aligning

This FIRST LEGO League robotics video tutorial is about the Treadmill mission and how it could be accomplished. The mission is from FLL 2020 RePlay competition. Almost every year there is a mission of this type where the robot must spend a lot of time with the mission model in order to turn or lift something. These are quite interesting and challenging missions.

This FRIST LEGO League video tutorial is about he Boccia Share mission from FIRST LEGO League 2020 RePlay competition. In the tutorial we demonstrate how to push on a lever to release a mission model part - in this case a box. You have the choice before the competition to cooperate with the other team and to decide if you are going to do the blue or the red box.

In this video tutorial we look at an active attachment that uses gear wheel and the attachment is general enough to be suitable for reuse. This means that a lot of different missions could be accomplished with the same attachment. The goal of the attachment is to transfer power to a lever through a system of axles and gear wheels. It is interesting that we change the orientation of the gear wheels.

In this video tutorial we use an active attachment with a gears, built only form LEGO Mindstorms Robot Inventor parts, to accomplish the FIRST LEGO League 2020 Treadmill mission. The goal of the mission is to rotate the mission model for a couple of seconds so that a pointer makes a half circle rotation. What you will learn is a good principle to approach such missions.

This is a 10 out of 10 tutorial demonstrating the accuracy of an active gear attachment that accomplishes the Treadmill mission from the FIRST LEGO League 2020 RePlay competition. When the robot is well aligned to the line before that it is easy for the robot to accomplish the mission. You will see how we make use of the friction of the wheel to rotate the mission model.