Investigating Tensegrity 2: Structures

My next step in tensegrity models is to create a tower. This however proved harder than anticipated. My first attempt was a square tower constructed from the same components as above. The tower can be created by stacking two of the basic prism shapes on top of each other. To prevent two of the compression members touching, the stacked prism will have to be rotated and connected on the top tension cords. The idea was that the tower could stand on its own without having to have points locked in space because of the torsion force. The torsion force can be counter acted by making each prism have the opposite structural helix. This means the torsion forces have the same managitude but act in opposing directions. Adding the force vectors gives a resultant of zero (or it should if the tower is created properly).

However the created tower above looks very little like a tower. This was caused by my own mistake with measuring the string for the tension cables. I underestimated the amount the elastic properties of the string and thus they are too loose to keep the structure in appropriate tension.

For the next tower I created two triangular prisms from straws and string. Because of the problems I had with the string's elasticity, I used more compression components to insure the tower's shape and integrity stayed optimum. While this still is a tensegrity structure, it doesn't really require that many compression struts.

Above are the two prism components. When I tried to attach them to each other, the straws collapsed and both prisms were ruined.

From these experiments I have learnt that I need better materials. The tension component needs to be less stretchy, something like fishing wire. The compression components need to be stronger, preferably solid wood or metal rods. Also bringing up the scale of the model will make connecting the wire to the struts easier and make studying the forces in motion easier to view.