A comparison of rate-limit compensation schemes for pilot-induced-oscillation avoidance

It is known that rate-limited actuators may be responsible for causing Category II pilot-induced-oscillations (PIO's). This paper presents a comparison between two industry-develope rate limit compensators and an H∞ compensator proposed in [C. Edwards, I. Postlethwaite, Anti-windup and bumpless transfer scheme, Automatica 24 (2) (1998) 199–210] and used in [M.C. Turner, D.J. Walker, A.G. Alford, Design and ground-based simulation of an H∞ limited authority control system for the Westland Lynx helicopter, Aerospace Science and Technology 5 (2001) 221–234]. These are tested on an industry-standard aircraft model called ADMIRE, with nonlinear simulations. Overall, it is shown that the H∞ compensator produces the best all-round performance for the input types considered, both in the pitch and the roll channels.