Layout and sizing optimization of discrete truss based on continuum

Abstract

A new method combined continuum topology with discrete truss is proposed for truss optimization. The optimized material distribution is obtained by means of continuum topology optimization and then transformed into initial truss. Based on the element principal stress and 8-neighborhood elements of continuum, force flow path extraction method is presented to obtain the initial truss layout. For section size optimization, criterion is deduced from a mathematical model by Lagrange multiplier method. Leveraging the free-form nature of continuum, this method can avoid the restriction of traditional ground structure. And it can achieve a better solution with less mass, smaller deformation and more uniform stress.