Design robust H_∞ -PID controller for a helicopter system using sequential quadratic programming algorithm

ABSTRACT

This paper proposes a new methodology for designing a controller for the tracking control problem in a 2 DoF helicopter system. The control problem is formulated as a nonlinear constraint optimization problem. Also, a sequential quadratic programming algorithm is applied to tune the PID gains according to the H infinity specifications. Tuning is done by selecting relevant objective functions and constraints. A nonlinear model of the 2 DoF helicopter is linearized and decoupled into two SISO systems (i.e. Yaw and Pitch models). Two independent controllers are designed for the models. For the purpose of demonstrating the robustness and superiority of the proposed method, the method is compared with a standard H infinity. Next, the performances of both controllers are examined. That allows the effects of system uncertainties, external disturbances and different tracking command signals take place.

KEYWORDS:

• Robust control
• H infinity
• PID
• SQP
• helicopter system

Disclosure statement

No potential conflict of interest was reported by the author(s).

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