Multilevel Optimization Approach Applied to Aircraft Nose Landing Gear

 

Vladimir Zeljković, PhD (Eng)

Stevan Maksimović, PhD (Eng)

 

General multilevel approach of large-scale multidisciplinary structural problems is considered. Optimization approach is applied to multidisciplinary structural problems like: minimum weight of aircraft nose landing gear structure under various strength and stiffness constraints, directional aircraft stability and control during taxiing and take off. Optimality criteria approach (Dual algorithms) and finite element method (FEM) for stress analyses, in system level, are applied to achieve minimum weight design of nose landing gear structure. Nonlinear mathematical programming (NMP) methods based on multicriteria optimization algorithms for Pareto optima (Weighting method), in local levels, are applied to stability maximization and turning capability of nose wheel structure. In local levels the nose wheel castering length and damping of damper are considered as optimization parameters in stability maximization and controllability during taxiing and take off. The use of finite element methods in parallel with optimization techniques such as dual and multicriterion optimization techniques make it possible to address large-scale and complex structural problems such as aircraft landing gear or composite structures.

 

Key words: multilevel optimization, aircraft landing gear, finite element method, optimality criteria, multicriterion optimization.