Abstract:

A lateraldirectional flight control system of a flyingwing unmanned aerial vehicle(UAV) must enable the UAV to exhibit excellent dynamic response and be insensitive to wind turbulence. At the same time, the controller must be simple enough to be easily applied in reality.Therefore a fixed structure H₂/H_∞ control method is proposed. To deal with the bilinear matrix inequality(BMI) that arises in the proposed method, the mapping of control law parameters and H₂/H_∞ performance is derived from linear matrix inequality (LMI) first, and then by taking the mapping as a fitness function, the optimal H₂/H_∞ performance and the control law parameters can be solved with the improved genetic algorithm. Simulation results show that when the UAV is under the disturbance of a lateral wind, the dynamic responses of the UAV with the fixed H₂/H_∞ controller are smooth and rapid and the oscillation amplitude of the angle of bank is only half of what could be obtained by the original classical controller.

Key words: H₂/H_&infin,  , control,  , fixed , structure,  , genetic , algorithm,  , linear , matrix , inequality,  , flight , control , law