In this episode we continue from Episode 55 and we improve the durability and stability of the attachment for a LEGO Mindstorms EV3 robot. Many times attachments are not very stable which results in gaps between parts. The goal of the video is to give basic construction ideas.
In this video lesson I am building a LEGO Mindstorms EV3 active attachment powered by a small gear wheel. The attachment could move up and down, it is very useful for collecting objects. It could easily be adapted and used on other robots.
We are making a parallel with Video Lesson 56 from the series and we are also showing ways to improve the stability of an axle which is most of the time neglected, but could lead to great problems.
Based on feedback from many of you in this episode I would like to show you how to build an active attachment that changes the orientation of a gear wheel placed vertically to a gear wheel placed horizontally. This attachment could be used in competitions and shows a basic principle of changing the orientation. All attachments could follow the same principle.
We are describing the Warm gear in this video. This worm gear does most of the magic of controlling how the different gear wheels move on the different axles.
In this episode we build a reusable attachment for a LEGO Mindstorms EV3 robot that changes gears orientation and direction. It is one of the most useful attachments that you could use to move levers up/down and right/left. Adding the attachment on the robot takes 2-3 seconds and shows a very useful general principle of how to build reusable attachments.
In this second video lesson on catapults we improve the stability of the base of the robot. An important feature of the new base is that it is not bending. Use the same principle in all of your constructions to achieve better, stronger robots.
В първа част от уроците за зъбни колела ви показахме основите на системите от зъбни колела. Сега ще разгледаме системи от зъбни колела с повече от две колела и каскадни зъбни предавки.
Part four of the Catapult series is again about loading the catapult automatically but this time using EV3 brick, motor and sensor. We use a gear system with a medium complexity along with a "standard clutch" available in the LEGO Mindstorms EV3 kits. As a result, at the end of the video, the Catapult loads and fires automatically.
Vision is still one of the very few fields where a human being could outsmart a computer. Still. Colour/Light sensors are the cornerstones of implementing a smart LEGO Mindstorms robot that could at least partially do "vision". In this video tutorial, we are using the robotics sensor to detect loading and unloading of the catapult.
Starting with the World Robotics Olympiad 2014 Junior-High challenge we first catch the object on our path. We discuss a good mechanism for catching and lifting balls that can do two movements with one motor.
Extend the previously build attachment for the FIRST LEGO League (FLL) Nature's Fury competition so that we can move the Truck and Ambulance up and down.
In the previous video, we found the correct answer for our task and it is 18.75, or is it?
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.
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.
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.
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"
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.
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.
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.
In this tutorial, we add another mission to our current program. This mission is - hanging the Gecko from the FIRST LEGO League Animal Allies.
Time to lift the robot. The first approach is by using the 40 teeth gear wheels that come with the LEGO Mindstorms EV3 and NXT robotics sets.