US Patent 11167395 Constant force expansion lattice

A constant force expansion construct includes a plurality of expandable layers, each expandable layer including: (a) a longitudinal restricting beam; and (b) a plurality of interconnected flexible biasing struts connecting the longitudinal restricting beam of one expandable layer to another longitudinal restricting beam in a next adjacent expandable layer, the biasing struts being biased toward a compressed position and being movable between the compressed position and an expanded position in which a distance between successive longitudinal restricting beams is increased.