Mixed H2/H∞ autopilot design of bank-to-turn missiles using fuzzy basis function networks

This paper presents a novel mixed H2/H∞ autopilot design for bank-to-turn missiles. Based on sliding control theory, the proposed autopilot utilizes a fuzzy basis function network to approximate the unknown nonlinear functions of bank-to-.turn missile dynamics, enabling a mixed H2/H∞ controller with weight updating laws to be applied to attenuate the effects of approximation errors and external disturbances. Moreover, the mixed H2/H∞ autopilot design can minimize H2 performance criteria under a desired H∞ disturbance rejection constraint. Unlike general mixed H2/H∞ control problems, the proposed H2/H∞ autopilot with self-tuning fuzzy basis function network can avoid solving coupled Riccati equations by adequately selecting diagonal weighting matrices in the H2 performance criterion and H∞ constraint. Therefore, the proposed H2/H∞ control approach can be implemented efficiently. Computer simulation results are presented to illustrate the effectiveness of the proposed mixed H2/H∞ autopilot for BTT missiles.