Integrated missile guidance and control: a state dependent Riccati differential equation approach

The need to engage tactical ballistic missile (TBM) threats and high performance anti-ship cruise missiles is dictating the design of enhanced performance missile interceptors that can provide a high probability of kill. It can be argued that current interceptor guidance and control (G&C) designs are suboptimal because each of the G&C components are designed separately before they are made to interact together as a single functional unit. Ultimately, integrated G&C (IGC) design techniques might improve interceptor performance because: 1) the implicit interdependency of the classically separate G&C components could provide a positive synergism that is unrealized in the more conventional designs, and 2) an IGC design is formulated as a single optimization problem thus providing a unified approach to interceptor performance optimization. The prototype IGC system discussed in this paper is designed via an approximate solution to the nonlinear disturbance attenuation problem. Furthermore, the integrated controller has been implemented in a high fidelity six-degree-of-freedom (6DOF) missile simulation that incorporates a fully coupled nonlinear aerodynamics model. A high-performance benchmark missile G&C system has also been designed and incorporated to provide performance comparisons. In addition to a discussion of the solution methodology, 6DOF Monte Carlo simulation results are presented that compare the integrated concept to the benchmark G&C system. The simulation results to date show the IGC paradigm reduces both the mean and I-sigma miss statistics as compared to the benchmark system.