A nonlinear pilot model for hover

Abstract

This paper deals with persistent oscillations in position and attitude observed in flight on a piloted VTOL during precision hover. Properties of the oscillation are shown to correlate strongly with Cooper-Harper pilot ratings. A simple yet nonlinear pilot model is developed which predicts many of the properties of the pilot-inthe-loop system behavior. Configuration 217CK+ N(E) PR ll s Tx Nomenclature = properties of the ideal relay with dead zone (Af=0.25 in., >1 =0.125 in.) = configuration C of X-22A flight 217 = error in X position, -X C -X (ft) = amplitude of sinusoidal input to nonlinear element N(E) = pilot position error gain (in./ft) = ratio of steady state x translational velocity per inch of pilot's stick position (ft/s/in.) . = minimum pilot position error gain to maintain a stable limit cycle (in./ft) = describing function gain which is a nonlinear function of sinusoidal input amplitude E = Cooper-Harper pilot rating (Ref. 1) = quantization nonlinearity, Fig.9 = Laplace operator for differentiation = equivalent path mode time constant, s = fore and aft position, ft = commanded position, ft = pilot's stick position (positive stick aft, in.) -modified stick position (positive stick forward, in.) = -d s = body-axis pitch attitude, deg = limit-cycle frequency

Fuzzy Control Strategies in Human Operator and Sport Modeling

“…All of these efforts employed some type of relay element to model the discontinuous input behavior. During the 1980's and 1990's, pilot models were developed that included switching or discrete changes in pilot behavior [25,26,27,28,11,12].…”

Human Operator Modeling and Lie-Derivative Based Control

“…All of these efforts employed some type of relay element to model the discontinuous input behavior. During the 1980's and 1990's, pilot models were developed that included switching or discrete changes in pilot behavior [26,27,28,29,12,13].…”