Optimum design of adaptive truss structures using the integrated force method

A structural analysis and optimization method is developed to find the opti mal topology of adaptive determinate truss structures under various impact loading conditions. The objective function is based on the maximization of the structural strength subject to geometric constraints. The dynamic struc tural analysis is based on the integrated finite element force method and t he optimization procedure is based on the Sequential Quadratic Programming (SQP) method. The equilibrium matrix is generated automatically through the finite element analysis and the compatibility matrix is obtained directly using the displacement-deformation relations and the Single Value Decomposi tion (SVD) technique. By combining the equilibrium and the compatibility ma trices with the force-displacement relations, the equations of the motion a re obtained with element force as variables. The proposed method is extreme ly efficient to analyze and optimize adaptive truss structures. It is obser ved that the structural strength is improved significantly using the adapti vely optimized geometries while the computational effort required by the fo rce method is found to be significantly lower than that of the displacement method.