LEGO Lab!

Jason and I have made a lego crane together. I was surprised how smart it is and how well fit it is each piece. Look at this picture! Even lego kit was amazingly organized. I really liked it.

It did not take long time to complete this crane. Actually it was such a well-designed equipment. The most impressive part of it was the red bar for preventing to turn the gear to opposit way. It allowed us to turn the gears just one way. - the second picture. Also it made a interesting sound hitting the gear when it was turned. And we were curious what two blue bars on the two arms are for, so just got rid of them to see the crane would work without them. As I heard in class, these blue ones helped two arms keep parallel. But we did not have any problem to make it work without them, maybe this crane was too small to use support of them. Except this, there were no redundant parts. I think LEGO shows the best minimum constraint design.


After done it, we tried to hang heavier stuff on the hook of the crane. It lifted up pretty heavy stuff easily and was stronger than I thought.

We played with it for a few minute and realized that to lift stuff we should turn the handle a lot. After looking at it again, Jason told me it was because of the small gear. Following Jason's explanation, it was same principle with a bycicle which has gears. When you ride a bycicle to go up to hill easily, you can change your gear of the bycicle; bigger one to smaller one. To spin the wheels, you pedal several times with the smaller gear with smaller energy but with the bigger gear you need more energy to pedal but fear times than smaller one. So to check this principle, we changed the small gear to the bigger one.

As expected, I could feel harder to turn the handle with a bigger gear but it helped to reduce turnning times. Harder to turn and fewer times vs easier to do and more times. In other words there is a same total energy. It looks like really simple logic but l learned a lot from this lab.