Onboard gauss pseudospectral terminal guidance law with multiple constraints

Aiming at hypersonic vehicles, a terminal guidance law satisfying the final position, dynamic pressure, normal overload constraints as well as the terminal attack direction and terminal velocity constraints, was studied. The optimal feedback control was obtained by solving the nonlinear optimal control problem using Gauss pseudospectral method. An initial guess strategy was imposed into the Gauss pseudospectral solving-process to accelerate the convergence speed. In the last guidance cycle, no feedback information was available. Therefore, the proportional navigation guidance was applied to ensure the impact accuracy. Monte-Carlo shooting experiment of three-degree-of-freedom model was conducted under the conditions of dispersion. The simulation result verifies that the onboard Gauss pseudospectral guidance law is stable and robust even in the highly dispersed cases.