Tensegrity Structure 2D — Compression Struts & Tension Cables

Prestress

Cable tension 50%

Interact

Drag any of the four gold node handles to pull the structure out of shape. Release it and the cables' tension pulls it back toward equilibrium while the struts hold their length.

Live Readouts

at rest

Strut A compression

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Strut B compression

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Max cable tension

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Taut cables

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How it works

This is the simplest possible tensegrity unit: two rigid struts (compression members) cross without touching — one passes slightly in front of the other, shown here as a small gap where the near strut breaks the line of the far one. Neither strut ever bears tension and neither cable ever bears compression.

Four cables (tension members) run around the outside, each connecting one end of strut A to one end of strut B, forming a closed loop. Because a cable can only pull, never push, the whole assembly only holds its shape when every cable is under enough tension to resist the struts trying to spread apart — this pre-tension is called prestress.

Each frame the sim runs a small spring-relaxation solve: cable forces (Hooke's law, one-sided — zero force once a cable goes slack) are summed at each node, the struts are then re-projected back to their exact rigid length, and velocities are damped. Raising the tension slider shortens each cable's natural (unstretched) length relative to the built geometry, increasing prestress and making the structure noticeably stiffer and quicker to recover from a drag; near 0% the cables approach their natural length, prestress collapses, and the structure goes slack and floppy.

Struts (compression) Cables (tension)