Video tutorials -

• LEGO MINDSTORMS EV3

This video is part of a series where we show you how our Box Robot accomplished the M07 Swing mission 10 times. This mission has a black and white line parallel right next to it, the only thing you need to figure out is how to avoid the first supporting beam of the swing. The Dominator robot waits to be clear of the beam and then uses the x-y movement of its front mottors to position the lever so it pushes the swing loose. After that the robot moves back and is ready for action again.

The video shows why you should not build attachments such as "Crappy Active Attachment For SUV Box Robot". In the video one can see how the knob gear wheels start "jumping", once a force is applied to the lever. 

In this video tutorial we would look at the mission run for M09. STRENGTH EXERCISE. The mission is to lift a heavy object in the air. And that could a complex mission. It requires to use gear wheel and the attachment should be quite strong. The tutorial contains only the mission run on the field. We accomplish a single mission. 

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

We've recently received a number of question on how could the SUV box robot be charged. The answer is simple - you detach the back pane. The question and topic of detaching modules from a robot and attaching them again is really interesting and powerfull and yet not very often implemented in many robots. 

There are a few main challenges with box robots and in the following tutorial we would like to resolve them. Read on and let's see how we could do this. 

The after season review continues. No. We are not publishing a single solution for the next season before it is over, but let's learn from the previous season. The current tutorial is about three missions at once on a single run with the robot. Most FIRST LEGO League teams try to accomplish one-two missions on a single run out of the base, and three is really what makes the difference

As we are already off the season we decided to look back at the competition. First, we will take a look at the working solution for FIRST LEGO League 2017 Manhole Cover. This was generally accepted as one of the most difficult missions during the competition. We've built a single attachment to accomplish it. 

(we are releasing the video without explanations and will add the explanations later)

Think of an attachment that leaves the Gecko on the mission model. Don't use the robot attachment that we already have. Just the box robot and the gecko. Nothing should support the Gecko when it is hanged on the mission model. 

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

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. 

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. 

How great is the great attachment for lifting that we built in this course? How many times can it lift the robot without making an error? How great are your attachments and how could you test them? - the answer is simple. Just try 10 times and they should work at least 9 of them as our attachment is.

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 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.

Connect the attachment to the box robot and find the correct number of rotations of the middle motor that would bring the robot up and forward and would attach it to the mission model.

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. 

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

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

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?

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.

Let us do a quick recap of the whole lifting mission and its solution

Note for the teacher on making the construction more stable, more durable and using beams for this.

Following the principles from the previous video, try to make the attachment that you've built, more stable and durable. 

In this video we discuss the durability of the construction of LEGO robots and how do we make them more durable.