Optimal dynamic fitting and identification of aerobomb´s fitting drag coefficient curve

An optimal dynamic fitting concept is proposed and applied to an aerodynamic coefficient curve identification problem. Extracting an aerobomb´s optimal fitting drag coefficient curve C_df(M) from three-dimensional theolodite film data is treated as an optimal tracking control problem, where C _df(M) is the control profile. This functional minimization problem is converted to a multivariable minimization problem. Cubic splines with deficiency 2 are used to guarantee the continuity and fitting flexibility of C_df(M). A quasi-Newton-Raphson iterative scheme is used to reduce the computational cost. The correction of initial states of trajectory equations is discussed. Practical test data reduction results for three bombing flight paths show that the optimal dynamic fitting concept has great potential in aerodynamic coefficient curve identification and in similar applications