Control of Rotor Blade Sailing Phenomenon (BSP)

With some modification the actuator placement optimization method described earlier can be applied to determine an optimized configuration/placement to integrate MFCs into active rotor blades. A feasibility study of open-loop control with integral active twist actuation which included different strategies for controlling BSP, recently concluded by Professor Afagh and his research group, has shown remarkable positive results as a proof of concept.

Investigating closed-loop control strategies with the required nonlinear system identification is the next step in this research program. This is a complicated task due to the nonlinear and highly transient nature of the problem.  However, at least as a first attempt, it is proposed that classical control schemes that rely on certain approximations of the system will be considered. One such scheme is gain scheduling, where the rotor system of the helicopter is approximated by a series of transfer functions with each function being approximately valid for a certain range of hub angular speed.

Design and implementation of a robust control scheme based on nonlinear control theory will be the final objective of this program. The validation of the control schemes will initially be carried out using a reduced model of a generic blade in our Applied Dynamics Laboratory before approaching the industry for a full-scale model of an integral active twist (IAT) blade.
 

“Experimental investigation of 1/12 th Froude-scaled flap articulated rotor system model during engage-disengage operations and when subjected to sea wave dynamics as represented by a 6 DOF motion table.”

“Experimental investigation of a 1/12 Froude-scaled flap articulated rotor system subjected to engage-disengage operations in the 2×3 meter wind tunnel at NRC-AIR facilities in Ottawa, Canada”