Robust sampled-data H_∞ -flight-controller design for high α stability-axis roll maneuver

This paper demonstrates a design application of a robust sampled-data H_∞-controller for a high-performance fighter aircraft executing a high α stability-axis roll maneuver. The performance of the sampled-data H_∞-controller is compared with that of the continuous-time H_∞-controller (based on the mixed-sensitivity and the closed-loop model matching approaches) and also of the conventional digital H_∞-controllers. At low sampling rates, nonlinear simulations show better performance using the sampled-data H_∞-controller than those of other controllers. The sampled-data H_∞-controller also has the advantage that the stability of the resulting closed-loop system is more tolerant to sampling time and controller gain uncertainties, thus leading to a more resilient and practical controller design approach.