Definition is adapted from here:
Tensegrity (K2 Rv8).gh (20.8 KB)
Kangaroo now just finds equilibrium between the struts and cables. Each node has one strut and four cables (i.e. 5-valent), so you could in theory omit one cable at each node and form-find this instead and it would probably be stable, but perhaps harder to string together in real-life. Meshes included for a tetrahedron and icosahedron.