Multi-objective Optimization for Resilient Operation of Morphing Flap

Abstract

This study considers the recoverability of the adaptive wing using morphing flaps divided in span direction. The recoverability is proposed as resilient operation that recovers the lifting force by adaptively changing the flap angles of the remaining flaps after one flap fails that the flap angle is returned back to zero, An efficient operation method is formulated as the multi-objective optimization problem with the three objectives in terms of the flap angles. The first is to minimize the difference of the lifting force before failures and after recovery from the viewpoint of flight mechanics, where the lifting force distribution is obtained by vortex lattice method. Though the third one can be formulated as a constraint condition, the formulation as the objective has several advantages to explicitly investigate the trade-off relationship. The remaining objectives are to minimize the bending moment at the wing root from the structural point of view, and to minimize sum of the flap angle differences for remaining flaps corresponding to the minimum effort of the operation. Through numerical examples, validity of the proposed resilient operation and hence the efficiency of the adaptive wing divided flaps are demonstrated.