Topology Optimization of Two-Dimensional Trusses Using Improved Particle Swarm Optimization

Abstract

This paper presents an improved particle swarm optimization (PSO) algorithm for solving topology optimization problems of 2D trusses under kinematic stability, stress, and displacement constraints. Although PSO is generally considered as an effective search algorithm for truss topology optimization, it tends to be trapped in local optimal regions. In PSO, each particle moves, each time, in a direction that is a combination of three directions, namely its current direction, the direction to the best particle, and the direction to the best position it has ever experienced. In this study, each particle considers, in addition to the above three directions, a trajectory toward or away from another randomly selected particle. If the randomly selected particle is better than the particle being considered, the particle will move toward this randomly selected particle; otherwise, it will move away in the opposite direction. These added information exchanges between particles increase the degree of exploitation of good solutions from different regions and reduce the occurrence of premature convergences. The obtained results show that the proposed algorithm performs effectively and provides better results than those obtained from the conventional PSO.