Multi-Objective Genetic Optimization for Helicopter Skid Landing Gears

This paper presents a numerical approach to the optimization of skid landing gears, basing on a genetic algorithm linked to a multi-body explicit code. The modelling technique is described and numerical-experimental correlations are presented regarding a drop test performed on a gear prototype. The numerical analyses are first used to point out the basic aspects of the gear design and to investigate the sensitivity of the gear behaviour to the characteristics of the skid-soil contact interaction. The optimization technique is applied to investigate the trade-off between the landing performances and the gear strength. The problem formulation is directed to minimize the load factor on hard soil with high friction coefficient and to optimize plastic strain distribution along the cross members. The Pareto's sets identified during the optimization searches allow to select promising design hypotheses which present acceptable overall landing performances, high efficiency and good strength and durability characteristics.