A TENSEGRITY STRUCTURE WITH BUCKLING COMPRESSION ELEMENTS - APPLICATION TO CELL MECHANICS

A tensegrity structure composed of six slender struts interconnected w ith 24 linearly elastic cables is used as a model of cell deformabilit y. Struts are allowed to buckle under compression and their post-buckl ing behavior is determined from an energy formulation of the classical pin-ended Euler column. At the reference state, the cables carry init ial tension balanced by forces exerted by struts. The structure is str etched uniaxially and the stretching force versus axial extension rela tionships are obtained for different initial cable tensions by conside ring equilibrium at the joints. Structural stiffness is calculated as the ratio of stretching force to axial extension. Predicted dependence s of structural stiffness on initial cable tension and on stretching f orce are consistent with behaviors observed in living cells. These pre dictions are both qualitatively and quantitatively superior to those o btained previously from the model in which the struts are viewed as ri gid.