A feasibility study of using smart materials for rotor control

Rotor actuation in the rotating system promises a quantum jump in overall rotor craft performance. Smart material actuator technology for operation 'on the blade' is now becoming available and has the potential to overcome the size, weight, and complexity issues of hydraulic and electric on-rotor actuation. The present paper is based on the results of a feasibility study to investigate the use of smart materials for primary and active control on the AH-64 helicopter. Based on the results of the study, it is seen that imbedded actuator concepts, i.e. pitch, twist, and camber control, are not practical at this time. Servoflap control, using hinged control surfaces driven by discrete actuators emerges as the most suitable candidate for smart material actuation. Preliminary data show that rotor control using smart materials might be feasible if a combination of smart materials is used and the rotor design is driven towards low control loads and motions.