Control of the Wing Rock Motion Using a New Suboptimal Control Method

Control of the non-linear wing rock motion of slender delta wing configurations using a new non-linear suboptimal control technique, denoted as the θ-D method, is discussed in this study. This new approach is based on series expansions and gives a closed-form suboptimal feedback solution to this non-linear control problem. The Hamilton-Jacobi-Bellman (HJB) equation is solved approximately by adding some perturbations to the cost function. The closed-loop system is generally guaranteed to be stable by manipulating the perturbation matrices properly. The numerical results of employing this method to the wing rock problem demonstrate that the θ-D suboptimal control can effectively suppress the wing rock phenemenon. It is also shown that the control design is not sensitive to the variation of roll moment coefficients at different angles of attack