A Real Time Scheme for Rotating System Component Load Estimation Using Fixed System Measurements

Accurate and real-time load monitoring of vital components located in the rotor system is important for not only inferring usage and estimating fatigue in those components, but also for developing load alleviation /limiting control schemes. An approach previously developed for online estimation of rotor component loads is evaluated in this paper in which a linear time invariant (LTI) model of helicopter coupled body/rotor dynamics is combined with a Linear Quadratic Estimator (LQE), that is designed to correct LTI model state response using fixed system measurements. The estimation fidelity of the LTI/LQE scheme is evaluated in simulations using a nonlinear model of a generic helicopter for online prediction of rotor blade pitch link loads arising from vehicle maneuvers.