Optimization of honeycomb impact attenuator using genetic algorithm based on response surface method and design of experiment; Part II: Optimization

In this study, honeycomb energy absorber is optimized using genetic algorithm. The design goal is to absorb whole impact energy within a ‎limited shock load level. First the crashworthiness and parameter sensitivity of honeycomb structure is extracted as explicit functions that ‎are utilized to find optimized shock absorber configuration. Energy absorber must depreciate the impact kinetic energy and mitigate its ‎defects on the structure and aboard. So the energy absorption capacity while the shock load is kept limited are the main design objectives. ‎The volume and mass restrictions are also important objectives from an application point of view. Based on the simulation results ‎available in the article Part I, the honeycomb response surfaces of crashworthiness parameters including the mean and peak crushing ‎stresses are extracted. Utilizing the genetic algorithm based on response functions, the multi-objective optimized energy absorber is ‎investigated. The main objective of the optimization problem is set to minimization of mass or volume while the maximum allowable shock ‎and minimum energy absorption capacity are included as the problem constraints. The geometric specifications of honeycomb structure ‎including cell-size, foil thickness, height and absorber face area are among the design variables with optimization outputs of energy ‎absorption capacity, volume, mass, and shock level. Some optimization results are compared with those available in the literature and a ‎typical problem is handled. Results show that mass and volume optimized geometries are almost similar and reduction of acceptable shock ‎level makes the optimized geometry height to rise.‎