Improving FLL Robot Game. Teacher's Notes. Durable and stable robots
Note for the teacher on making the construction more stable, more durable and using beams for this.
- #465
- 04 Apr 2017
Separate the robot construction on body - body and attachments. Attachments should be small, light and most importantly for winning the competitions they should be pinless. In this category we group tutorials, courses and materials for different attachments that have proved to be useful.
Note for the teacher on making the construction more stable, more durable and using beams for this.
Let us do a quick recap of the whole lifting mission and its solution
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.
In this video we discuss how do we transfer power from the motors that are "inside the robot box" to the gear wheels that are "outside the robot box".
Without the use of any motor, you can still accomplish a number of missions using passive attachments. You can still pull/push on different levers using only a beam or two connected to the frame.
Second active pinless attachment for the robot construction. It is placed in the top/right corner of the robot and includes an interesting gear system for transferring the power. The attachment is suitable for complete rotations.
This is a third example for adding an active attachment. This third attachment is now connected to the wheel at the front of the robot. Again, the attachment could be easily extended.
One more example for an active attachment with a system of gear wheels. This time the system is constructed so that the attachment could lift heavy objects.
We should how to build a frame that could hold the attachments for specific competition missions. This frame is added in a pinless manner. This means very fast and easy without any glitches of the pins.
This is the first Active Pinless Attachment for the Box competition robot. The attachment is placed on the top of the robot and is controlled by one of the motors.
In this video we discuss the durability of the construction of LEGO robots and how do we make them more durable.
Following the principles from the previous video, try to make the attachment that you've built, more stable and durable.
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.