Stochastic and deterministic analysis of nonlinear missile engagement scenarios using 5-dof 6-dof and adjoint models

Sezer, Emrah
In this study, pseudo five degree of freedom and a linear time varying adjoint models are considered in terms of their fidelity for conceptual design phase of a missile. The models are developed and compared for two analysis types such as, deterministic and stochastic. For the first analysis, pseudo five degree of freedom and adjoint models, which are developed, are compared with fully nonlinear six degree of freedom model for various performance analyses that are essential for conceptual design phases. Adjoint model includes time varying phenomena as an improvement over time invariant utilization, which exists in the literature. In the pseudo five degree of freedom model, roll dynamics is discarded and transfer function is implemented to represent missile acceleration response. The model includes improvements such as, more accurate drag coefficient estimation by using three dimensional incidence angle predictions, and better lateral angular dynamics estimation by using flight path kinematic equations. In addition, state space structured adjoint model is constructed and states are populated by obtaining a nonlinear model to capture the effects of engagement nonlinearity. Therefore, a proper linear time varying model is constructed and validated by comparing with nonlinear model. Finally, an approach is explained for stochastic disturbances for adjoint analysis.


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Citation Formats
E. Sezer, “Stochastic and deterministic analysis of nonlinear missile engagement scenarios using 5-dof 6-dof and adjoint models,” M.S. - Master of Science, Middle East Technical University, 2015.