Buckminster Fuller & Tensegrity

[Joe W.]

Believe it or not, this is a pattern in SG's collection.
I also checked out some UTube videos after cutting out the pattern to look for tips on assembly.  Found lots of videos of people who made them a lot bigger.
This one is 9 inches tall by 8 inches wide at the top and 6 inches at the bottom from 1/4 inch Birch PW and 12 pound test fishing line.
Oh, and there is a fourth line in back, but you can't see it well in these photos.
The figure is just over a pound in weight.  I stopped there.
It does make me wonder what the limits could be though.
Any engineers in the building?
 

Edited March 16, 2021 by Joe W.

[teachnlearn]

Its called 'Center of Mass'. Used for all kinds of designs. Its 'generally' to be simple a point that is placed on the object which is like the center of a teeter totter. If the point or CM is way low to the road for a car it will hug the road, take turns at high speeds and the car will not tip. Put the center of mass up on the roof of a car and a light wind will tip it over.

People that take chairs and stack them in weird shapes, then balance on them are adjusting their bodies, so the center of mass doesn't raise up toward them, then they fall off. RJF

Don't know if I should have posted this, now the magic and mystery, is gone.

Edited March 16, 2021 by teachnlearn
added line

[amazingkevin]

Pretty cool!!?

[jollyred]

I made one of those a few months back.  Freaked out my wife.  Then I made one using just one string.

[teachnlearn]

Your project is designed with 'vector forces'. Gravity pushing down, each piece pushing in different directions. Kind of like someone using their fingers and pushing side to side to keep a broom balanced upright. When all the forces cancel each other out you have hit equilibrium.  The other model works balancing around two strings each 'vector force' canceling out others. After working it out on paper the proof is a model the does what the calculations work out.

Heck of a lot of fun, just to get out wood blocks, or cut a bunch of shapes and play with the stack.

Our bodies do this self correction constantly, standing, moving, running, walking, and we continue to be upright, all while gravity 'wants too' tip us right on to the ground! All done at a young age with no knowledge of center of mass or vector forces!   RJF

[teachnlearn]

Realized, the original post asked the question of how tall this could go.  I covered 'vector force' which is going to put a specific amount of force on the project material. The breaking strength of the material is going to be a factor, along with its weight or 'density'. The weight, 'mass', is going to increase as the project grows. My guess with plywood is the balance project could go 2 to three stories. Plywood is used for two to three story buildings, with 'structure bracing' the building, so it doesn't tip. The vectors still have to cancel out for the building to stand.

The strength of the 'fishing line' and the breaking strength of it, would factor in.

Up the material to metal and we have sky scrapers. Seen some beautiful art projects done with steel beams and cables.

'AND NOW BACK TO YOUR REGULARLY SCHEDULED SCROLL SAW FORUM'

Sorry guys, science, taking things apart, creating stuff, has been a life time addiction. Ask a question like this is like waving a fresh salmon to a hungry bear. RJF

[Joe W.]

1 hour ago, teachnlearn said:

Sorry guys, science, taking things apart, creating stuff, has been a life time addiction. Ask a question like this is like waving a fresh salmon to a hungry bear. RJF

Hey Rick, 
no, thanks for taking the time to provide more info.
While I'm not the brainy type, I make up for it in curiosity.  Seeing something like this just make me stop and go "Hmmmm".
I have a son-in-law who has a similar affliction and I know he is just gonna flip when he comes by and sees this.
And when it comes to scroll sawing, it's opened up a whole new range of possibilities and uses for me - just yesterday I cut a bolt in half for a repair job.  Love this new toy!