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Full-Text Articles in Aerospace Engineering
Optimal Sizing And Control Of Hybrid Rocket Vehicles, Srija Ryakam
Optimal Sizing And Control Of Hybrid Rocket Vehicles, Srija Ryakam
Doctoral Dissertations and Master's Theses
In the present work, a genetic algorithm is used to optimize a hybrid rocket engine in order to minimize the propellant required for a specific mission. In a hybrid rocket engine, the mass flow rate of the oxidizer can be throttled to enhance the performance of the rocket. First, an analysis of the internal ballistics and the ascent trajectory has been carried out for different mass flow rates of the oxidizer as a function of time, for a fixed amount of oxidizer, in order to study the effect of throttling. Two equivalent problems are considered: in the first problem the …
A Radial Basis Function Method For Solving Optimal Control Problems., Hossein Mirinejad
A Radial Basis Function Method For Solving Optimal Control Problems., Hossein Mirinejad
Electronic Theses and Dissertations
This work presents two direct methods based on the radial basis function (RBF) interpolation and arbitrary discretization for solving continuous-time optimal control problems: RBF Collocation Method and RBF-Galerkin Method. Both methods take advantage of choosing any global RBF as the interpolant function and any arbitrary points (meshless or on a mesh) as the discretization points. The first approach is called the RBF collocation method, in which states and controls are parameterized using a global RBF, and constraints are satisfied at arbitrary discrete nodes (collocation points) to convert the continuous-time optimal control problem to a nonlinear programming (NLP) problem. The …