ACTUATION CONCEPTS FOR MORPHING HELICOPTER ROTOR BLADES

摘要

Actuation concepts for deforming helicopter rotor blades with the aim to control rotor aerodynamics are presented. Focus is on blade twist and airfoil camber variation and the two relevant aerodynamic working principles, I.e. direct lift and servo effect are discussed. The proposed actuation concepts are based on piezoceramtic actuation with focus on d33-mode. These actuation concepts are analysed in detail. Comparison of different configurations is accomplished. For the Active Trailing Edge concept, results of aero-servo-elastic optimization studies and the corresponding actuator performance in terms of aerodynamic effectiveness as well as actuator mass are presented. Furthermore, integration issues, relevant requirements and restrictions are discussed. Finally, piezoceramic actuator arrays developed for the Active Trailing Edge concept are presented.