Intelligent mixed H2/H∞ FOPID controller optimized for radar guided missile

A mixed weighted H
₂
/H
_∞
tuning algorithm for fractional order PID controller is introduced and optimized for missile guidance system. The missile dynamics are highly nonlinear and the performance of the controller is usually degraded near the impact region which could cause the missile to miss the target. Therefore, a new tuning strategy is introduced to put weights for H
₂
/H
_∞
which depends on the range between the missile and the target. The introduced tuning procedure makes the controller more optimized in tracking the target near the impact region and eventually hit the target with more accuracy and less miss distance. Genetic algorithm is used to search the space for minimum H
₂
/H
_∞
value especially near the impact region. The control system is compared with Zeigler-Nichols tuning method applied on the standard PID controller, and the simulation results demonstrated the accuracy and superiority of the proposed controller over the conventional one.