Design methodology of flexible structures by spring-and-segment model

A design methodology of flexible structures is presented for the enrichment of the structural function by utilizing the mechanism realized by the larg e elastic deformation of flexible members. The flexible member is modeled b y straight bar segments linked by virtual coil springs. Its large deformati on is analyzed by the Lagrange multiplier method, the functional of which i s constituted in line with the principle of stationary potential energy wit h constraints on geometrical boundary conditions. The sensitivity analysis is formulated especially for the solution obtained by the Lagrange multipli er method so as to approximate the change of the structural response in the first-order sense with respect to design variables. Owing to the sensitivi ty analysis, governing equation of the design variables to realize the pres cribed structural performance is derived as the linear simultaneous equatio ns. The solution of design variables is determined by the Moore-Penrose gen eralized inverse since the coefficient matrix becomes rectangular.