How does this castle float?

[ukbajadave]

Came across this on another non Lego forum. I assume its maybe something to do with balance or maybe its photoshop magic but I just cant figure it out. Can anyone shed some light on the principle?

Pic from original thread, not mine. I would ask on the other forum but I'm not registered there, I just browse.

[dr_spock]

Physics.  Equililbrium of forces. 

 

[JGW3000]

Its called Tensegrity, check out JK Brickworks video on YouTube: 

(or its just Photoshopped)

Edited April 21, 2020 by JGW3000

[ukbajadave]

Thanks @dr_spock and @JGW3000

I've watched the video, read the wikipedia page and it still blows my mind! I think even if I build something myself it will still seem like magic. 

 

[1963maniac]

Yea, google "tensegrity" and check out the images.

[Vindicare]

That castle one is impressive! I’ve very seen these popping up on Instagram the last couple days. Pretty cool.

[MAB]

Presumably the strings going under the studs on the top section are being held by more than just that one round stud.

[dr_spock]

Those strings are at an angle on the top section. Besides clutch power, I think there is some additional force applied to holding the string stud down into the castle plate stud.  That amount of force is the tension force on the string times the sine of the angle.   Or something like that...bad memories of high school physics... 

 

 

[ukbajadave]

Being a technic kind of guy I threw this together to see it for myself. It's absolutely crazy once you get it balanced you can gently tap down on the top of the long chains and they spring back up! The tyre is needed as the top arm needs to be heavy on the back edge. I made a bricklink wanted list for the JK Brickworks Tensegrity sculpture so I can build one to display.

[koalayummies]

We have been contact tracing these for a few weeks. One person posted one of these on reddit and now all the top Lego posts are these things. It is spreading rapidly. In order to protect as many Lego builders as possible from Tensegrity-20 we are issuing tensegrity-distancing measures.

[MAB]

23 hours ago, koalayummies said:

... we are issuing tensegrity-distancing measures.

Is that a limit in the length of the chains that can be used ...? :-)

 

[Beleg the Ranger]

There is a Challenge on Lego Ideas right now about Tensegrity.