Finalized. Wish me luck!
This commit is contained in:
@@ -35,10 +35,10 @@
|
||||
|
||||
\subsection{Motivation}
|
||||
|
||||
\begin{frame} \frametitle{Motivation}
|
||||
How can we leverage existing technologies and techniques to determine
|
||||
optimally-controlled trajectories to targets in interplanetary space?
|
||||
\end{frame}
|
||||
% \begin{frame} \frametitle{Motivation}
|
||||
% How can we leverage existing technologies and techniques to determine
|
||||
% optimally-controlled trajectories to targets in interplanetary space?
|
||||
% \end{frame}
|
||||
|
||||
\note{Today I'll be discussing my research in determining optimal trajectories
|
||||
for interplanetary mission objectives. Numerous scientific and engineering advances have
|
||||
@@ -96,50 +96,17 @@
|
||||
thrust nature changes the underlying system dynamics that would have been used to optimize a
|
||||
mission such as Voyager, which did not employ low-thrust engines.}
|
||||
|
||||
% \begin{frame} \frametitle{Current tools}
|
||||
% Indirect Methods:
|
||||
% \begin{itemize}
|
||||
% \item CHEBYTOP
|
||||
% \item NEWSEP
|
||||
% \item SEPTOP
|
||||
% \item VARITOP
|
||||
% \end{itemize}
|
||||
|
||||
% Direct Methods:
|
||||
% \begin{itemize}
|
||||
% \item EMTG
|
||||
% \item GALLOP
|
||||
% \item MALTO
|
||||
% \item PAGMO
|
||||
% \end{itemize}
|
||||
% \end{frame}
|
||||
|
||||
% \note{However, many interesting techniques have been developed to combat this issue,
|
||||
% particularly in recent years. A number of different algorithms have been developed }
|
||||
|
||||
% \subsection{Scope}
|
||||
|
||||
% \begin{frame} \frametitle{First Frame}
|
||||
% \begin{itemize}
|
||||
% \item Item 1
|
||||
% \item Item 2
|
||||
% \end{itemize}
|
||||
% \end{frame}
|
||||
|
||||
% \subsection{Problem Statement}
|
||||
|
||||
% \begin{frame} \frametitle{First Frame}
|
||||
% \begin{itemize}
|
||||
% \item Item 1
|
||||
% \item Item 2
|
||||
% \end{itemize}
|
||||
% \end{frame}
|
||||
\begin{frame} \frametitle{Problem Statement}
|
||||
For a given low-thrust engine, spacecraft parameters, and planetary flyby selections,
|
||||
what is the optimal control thrusting profile, launch conditions, and flyby parameters
|
||||
to arrive at a target outer planet?
|
||||
\end{frame}
|
||||
|
||||
\section{Trajectory Optimization Background}
|
||||
|
||||
\subsection{System Dynamics}
|
||||
|
||||
\begin{frame} \frametitle{Two Body Problem}
|
||||
\begin{frame} \frametitle{Dynamical Model: Two Body Problem}
|
||||
\begin{columns}
|
||||
\begin{column}{0.45\paperwidth}
|
||||
Assumptions:
|
||||
@@ -167,7 +134,7 @@
|
||||
which it is orbiting. Secondly, both of these bodies are modeled as point masses with
|
||||
constant mass. This removes the need to account for non-uniform densities and asymmetry.}
|
||||
|
||||
\begin{frame} \frametitle{Two Body Problem}
|
||||
\begin{frame} \frametitle{Dynamical Model: Two Body Problem}
|
||||
\begin{columns}
|
||||
\begin{column}{0.45\paperwidth}
|
||||
\begin{align*}
|
||||
@@ -187,7 +154,7 @@
|
||||
\note{From Newton's second law and the law of universal gravitation, we can then model this
|
||||
force with this equation. Where...}
|
||||
|
||||
\begin{frame} \frametitle{Two Body Problem}
|
||||
\begin{frame} \frametitle{Dynamical Model: Two Body Problem}
|
||||
\begin{columns}
|
||||
\begin{column}{0.45\paperwidth}
|
||||
\begin{equation*}
|
||||
@@ -206,7 +173,7 @@
|
||||
|
||||
\note{Dividing by the mass, we can derive the acceleration...}
|
||||
|
||||
\begin{frame} \frametitle{Two Body Problem}
|
||||
\begin{frame} \frametitle{Dynamical Model: Two Body Problem}
|
||||
\begin{columns}
|
||||
\begin{column}{0.45\paperwidth}
|
||||
\begin{align*}
|
||||
@@ -228,7 +195,7 @@
|
||||
parameter as a function of the planetary mass alone, rather than both combined. With this
|
||||
assumption, we can model the system dynamics with this analytically solvable equation}
|
||||
|
||||
\begin{frame} \frametitle{Kepler's Laws}
|
||||
\begin{frame} \frametitle{Dynamical Model: Kepler's Laws}
|
||||
\begin{itemize}
|
||||
\item Each planet's orbit is an ellipse with the Sun at one of the foci.
|
||||
\item The area swept out by the imaginary line connecting the primary and secondary
|
||||
@@ -241,7 +208,7 @@
|
||||
\note{In the early 1600s, Johannes Kepler determined three laws in order to describe the
|
||||
motion of a satellite. These are:}
|
||||
|
||||
\begin{frame} \frametitle{Kepler's Laws}
|
||||
\begin{frame} \frametitle{Dynamical Model: Kepler's Laws}
|
||||
\begin{equation*}
|
||||
r = \frac{\sfrac{h^2}{\mu}}{1 + e \cos(\theta)}
|
||||
\end{equation*}
|
||||
@@ -263,7 +230,7 @@
|
||||
actually take them a step further, producing the following extremely useful equations for
|
||||
representing spacecraft motion:}
|
||||
|
||||
\begin{frame} \frametitle{Kepler's Equation}
|
||||
\begin{frame} \frametitle{Dynamical Model: Kepler's Equation}
|
||||
\begin{equation*}
|
||||
\frac{\Delta t}{T} = \frac{E - e \sin E}{2 \pi}
|
||||
\end{equation*}
|
||||
@@ -295,7 +262,7 @@
|
||||
|
||||
\subsection{Interplanetary Trajectories}
|
||||
|
||||
\begin{frame} \frametitle{Patched Conics}
|
||||
\begin{frame} \frametitle{Interplanetary Trajectories: Patched Conics}
|
||||
\begin{figure}[H]
|
||||
\centering
|
||||
\includegraphics[height=0.7\paperheight]{LaTeX/fig/patched_conics}
|
||||
@@ -310,7 +277,7 @@
|
||||
sub-trajectories, each governed by a distinct single body when the spacecraft is within the
|
||||
sphere of influence of that particular body...}
|
||||
|
||||
\begin{frame} \frametitle{Gravity Assist}
|
||||
\begin{frame} \frametitle{Interplanetary Trajectories: Gravity Assist}
|
||||
\begin{figure}[H]
|
||||
\centering
|
||||
\includegraphics[height=0.7\paperheight]{LaTeX/fig/flyby}
|
||||
@@ -326,7 +293,7 @@
|
||||
|
||||
\subsection{Low Thrust Trajectories}
|
||||
|
||||
\begin{frame} \frametitle{Sims-Flanagan Transcription}
|
||||
\begin{frame} \frametitle{Low Thrust Trajectories: Sims-Flanagan Transcription}
|
||||
\begin{columns}
|
||||
\begin{column}{0.45\paperwidth}
|
||||
\begin{itemize}
|
||||
@@ -351,7 +318,7 @@
|
||||
trajectories with a single impulsive thrust in the center of each. Effectively, this
|
||||
allows...}
|
||||
|
||||
\begin{frame} \frametitle{Control Vector Description}
|
||||
\begin{frame} \frametitle{Low Thrust Trajectories: Control Vector Description}
|
||||
\begin{columns}
|
||||
\begin{column}{0.45\paperwidth}
|
||||
\begin{align*}
|
||||
@@ -607,6 +574,26 @@
|
||||
|
||||
\section{Conclusion}
|
||||
|
||||
\begin{frame} \frametitle{Conclusion}
|
||||
\begin{itemize}
|
||||
\item Validation of direct approach to optimizing interplanetary, low-thrust
|
||||
trajectories as non-linear programming problems
|
||||
\item Validation of Monotonic Basin Hopping algorithm for finding global optima in the
|
||||
same scenario
|
||||
\item Application in a realistic sample mission revealed two effective trajectory
|
||||
possibilities
|
||||
\end{itemize}
|
||||
\end{frame}
|
||||
|
||||
\begin{frame} \frametitle{Future Work}
|
||||
\begin{itemize}
|
||||
\item Outer loop which chooses optimal flyby trajectories for increased automation
|
||||
\item Parallelization would be effective for this problem
|
||||
\item Better quantification of search space ``coverage'' by the monotonic basin hopping
|
||||
algorithm
|
||||
\end{itemize}
|
||||
\end{frame}
|
||||
|
||||
\begin{frame}
|
||||
\begin{center}
|
||||
\begin{Huge}
|
||||
|
||||
Reference in New Issue
Block a user