Development of a 1/4-scale NiTinol actuator for reconfigurable structures

Wind Tunnel tests of a NiTinol based actuator have been conducted for the reconfigurable rotor blade program. The purpose of the test was to demonstrate the potential to improve rotorcraft performance by optimizing the configuration of major structures in flight. The actuator is integrated into the rotor blade as a structural element controlling blade twist. A three-blade scale rotor was tested in a Boeing wind tunnel. The tests validated actuator design and performance by demonstrating simultaneous blade twist and control of twist position over the entire test matrix. A description of system requirements and compromises associated with the actuator and its integration into the rotor blade are provided and discussed. Test results showed that the RRB actuators were able to successfully twist the blade, control the twist between one twist state and the other, and simultaneously control three rotor blades to change state within two seconds of each other despite unanticipated electrical noise in the system.