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proptalk-act1.tex
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\begin{frame}
\frametitle{Part 1: Capturing the Planning/Execution Tradeoff}
\begin{tikzpicture}
\draw[step=1,black!15,very thin,opacity=\gridopacity] (0,0) grid (12,8);
% figure adapted from proposal doc
\begin{scope}[font=\scriptsize,shift={(1.5,6.25)}]
% root sets
\node[draw,black,rounded corners,minimum height=1.5cm,minimum width=1cm]
(Xgrasp) at (3,0) {};
\node[above=0cm of Xgrasp] {Grasp};
\node[draw,black,rounded corners,minimum height=1.5cm,minimum width=1cm]
(Xdrop) at (6,0) {};
\node[above=0cm of Xdrop] {Place};
% nodes
\node[circle,fill=black,inner sep=2] (xstart) at (0,0) {};
\node[above=0.1cm of xstart] {$q_{\mbox{\scriptsize start}}$};
% grasp choices
\node[circle,fill=black,inner sep=2] (xg1) at (2.8,0.5) {};
\node[circle,fill=black,inner sep=2] (xg2) at (3.1,0.1) {};
\node[circle,fill=black,inner sep=2] (xg3) at (2.9,-0.5) {};
% place choices
\node[circle,fill=black,inner sep=2] (xd1) at (5.9,0.3) {};
\node[circle,fill=black,inner sep=2] (xd2) at (6.0,-0.4) {};
% xend
\node[circle,fill=black,inner sep=2] (xend) at (9,0) {};
\node[above=0.1cm of xend] {$q_{\mbox{\scriptsize end}}$};
\draw[line width=1.5mm,white]
(xstart) .. controls (1,0.2) and (1.4,0.9) .. (xg1);
\draw[line width=1.5mm,white]
(xstart) .. controls (1.5,0.2) .. (xg2);
\draw[line width=1.5mm,white]
(xstart) .. controls (1.8,-0.6) and (1.6,-0.8) .. (xg3);
\draw
(xstart) .. controls (1,0.2) and (1.4,0.9) .. (xg1);
\draw
(xstart) .. controls (1.5,0.2) .. (xg2);
\draw
(xstart) .. controls (1.8,-0.6) and (1.6,-0.8) .. (xg3);
\draw[line width=1.5mm,white]
(xg1) -- (4.7,0.6);
\draw
(xg1) -- (4.7,0.6);
\draw[line width=1.5mm,white]
(xg2) .. controls (4.5,1) and (3.5,-1.2) .. (4.5,-0.4)
.. controls (5.5,0.5) and (5.0,-1.3) .. (xd2);
\draw
(xg2) .. controls (4.5,1) and (3.5,-1.2) .. (4.5,-0.4)
.. controls (5.5,0.5) and (5.0,-1.3) .. (xd2);
\draw[line width=1.5mm,white]
(xg3) .. controls (4.3, 0.2) and (4.5,-0.2) .. (xd1);
\draw
(xg3) .. controls (4.3, 0.2) and (4.5,-0.2) .. (xd1);
% in s3
\draw[line width=1.5mm,white]
(xd1) .. controls (8,0.3) and (8,0.1) .. (xend);
\draw
(xd1) .. controls (8,0.3) and (8,0.1) .. (xend);
\node[fill,black,rounded corners,minimum height=1.5cm,minimum width=1cm,
opacity=0.1] at (3,0) {};
\node[fill,black,rounded corners,minimum height=1.5cm,minimum width=1cm,
opacity=0.1] at (6,0) {};
\end{scope}
\fill[green!20] (0.1,3.7) rectangle (11.9,4.3);
\node[anchor=north] at (6,5) {\begin{minipage}{11.5cm}
Planning for manipulation tasks poses three challenges:
\begin{itemize}
\item Challenge 1: Capturing the planning/execution tradeoff.
\item Challenge 2: Incongruent steps impede reuse.
\item Challenge 3: Coupled steps require long planning horizons.
\end{itemize}
\end{minipage}};
\end{tikzpicture}
\end{frame}
%\begin{frame}
% \begin{center}
% \Large
% How can we extend roadmap-based methods to reason
% about both \emph{planning} and \emph{execution} effort?
% \end{center}
%\end{frame}
\begin{frame}
\frametitle{The Planning vs. Execution Tradeoff on Roadmaps}
\begin{tikzpicture}
\draw[step=1,black!15,very thin,opacity=\gridopacity] (0,0) grid (12,8);
\node[inner sep=0] at (9,5) {%
%{\only<1>{\includegraphics{build/talk-act1-2d,rootsonly}}}%
{\only<1-2>{\includegraphics{build/talk-act1-2d,cfree}}}%
%{\only<3>{\includegraphics{build/talk-act1-2d,paths}}}%
{\only<3>{\includegraphics{build/talk-act1-2d,graph}}}%
{\only<4->{\includegraphics{build/talk-act1-2d,astara}}}%
};
\node[draw,circle,inner sep=2pt,ultra thick,fill=red!50] at (7.05, 2.0) {};
\node[draw,circle,inner sep=2pt,ultra thick,fill=green!50] at (7.5, 2.0) {};
\node[anchor=west] at (7.9,2.0) {start, goal configs};
\node[anchor=west,draw,line width=1pt,fill=blue!20,minimum width=0.75cm,minimum height=0.10cm]
(Cfreebox) at (6.9, 1.5) {};
\node[anchor=west] at (7.9,1.5) {$\mathcal{C}_{\mbox{\scriptsize free}}$};
\only<2->{
\node[anchor=north,fill=black!15,rounded corners] at (3,7.5)
{\bf Focus: Roadmap methods};
}
\only<5-6>{
\node[anchor=north,fill=blue!20,rounded corners] at (3,6.5)
{\begin{minipage}{5.5cm}
1. Searching roadmap graphs
- survey of search methods
- propose new algorithm E$^8$
\end{minipage}};
}
\only<7->{
\node[anchor=north,fill=green!20,rounded corners] at (3,6.5)
{\begin{minipage}{5.5cm}
1. Searching roadmap graphs
- survey of search methods
- propose new algorithm E$^8$
\end{minipage}};
}
\only<6->{
\node[anchor=north,fill=blue!20,rounded corners] at (3,4.5)
{\begin{minipage}{5.5cm}
2. Research questions
- graphs in C-space
\end{minipage}};
}
\end{tikzpicture}
\end{frame}
\begin{frame}
\frametitle{Efficiency in Graph Search}
\begin{tikzpicture}
\draw[step=1,black!15,very thin,opacity=\gridopacity] (0,0) grid (12,8);
% example (FIRST) problems
\only<4-14>
{
\node[inner sep=0pt] at (6.5,7) {\includegraphics[width=1.5cm]{figs/rubik.png}};
\node[inner sep=0pt,anchor=north,align=center,font=\scriptsize] at (6.5,6) {$4.3 \times 10^{19}$\\vertices};
}
\only<5-14>
{
\node[inner sep=0pt] at (8.5,7) {\includegraphics[width=1.5cm]{figs/15puzzle.png}};
\node[inner sep=0pt,anchor=north,align=center,font=\scriptsize] at (8.5,6) {$2.1 \times 10^{13}$\\vertices};
}
\only<6-14>
{
\node[inner sep=0pt] at (10.5,7) {\includegraphics[width=1.5cm]{figs/goldberg-northwest.png}};
\node[inner sep=0pt,anchor=north,align=center,font=\scriptsize] at (10.5,6) {1.6M\\vertices};
}
% example problems SECOND
\only<17->
{
\node[inner sep=0pt] at (2.0,7) {\includegraphics[width=2.5cm]{figs/fridge-intro.png}};
\node[inner sep=0pt,anchor=north,align=center,font=\scriptsize] at (2.0,6) {$\sim10$k\\vertices};
}
\only<18->
{
\node[inner sep=0pt] at (5.0,7) {\includegraphics[width=2.5cm]{figs/prm.png}};
\node[inner sep=0pt,anchor=north,align=center,font=\scriptsize] at (5.0,6)
{Motivation: PRM$^\dag$};
% cite
%\node[anchor=east,font=\scriptsize] at (12,0.5)
% {$^\dag$ Kavraki, Svestka, Latombe, Overmars, 1996.};
}
% draw graph box
\only<1-2>{
\node[draw,align=center,minimum height=1.3cm,anchor=south east] at (5,3.5) {
Graph\\$G = (V,E)$\\\includegraphics[width=1cm]{build/roadmap-2d-simple}
};
}
\only<3-15>{
\node[draw,align=center,minimum height=1.3cm,anchor=south east] at (5,3.5) {
Graph\\$G = (V,E)$\\\includegraphics[width=3cm]{build/roadmap-2d-simple}
};
}
% grow using a*!
\only<7-14>{
\fill[white,fill opacity=0.9] (1.8,3.6) rectangle (4.9,6.7);
\begin{scope}
\clip (1.8,3.6) rectangle (4.9,6.7);
\only<7>{\clip[rotate around={15:(2.0,4.8)}] (2.0,4.8) ellipse (0.5cm and 0.25cm);}
\only<8>{\clip[rotate around={15:(2.0,4.8)}] (2.0,4.8) ellipse (1.0cm and 0.50cm);}
\only<9>{\clip[rotate around={15:(2.0,4.8)}] (2.0,4.8) ellipse (1.4cm and 0.70cm);}
\only<10>{\clip[rotate around={15:(2.0,4.8)}] (2.0,4.8) ellipse (1.6cm and 0.80cm);}
\only<11>{\clip[rotate around={15:(2.0,4.8)}] (2.0,4.8) ellipse (1.9cm and 0.85cm);}
\only<12>{\clip[rotate around={15:(2.0,4.8)}] (2.0,4.8) ellipse (2.1cm and 1.05cm);}
\only<13-14>{\clip[rotate around={15:(2.0,4.8)}] (2.0,4.8) ellipse (2.2cm and 1.10cm);}
\node[align=center,minimum height=1.3cm,anchor=south east] at (5,3.5) {
\includegraphics[width=3cm]{build/roadmap-2d-simple}};
\only<14>{\draw[rotate around={15:(2.0,4.8)},line width=4pt]
(2.0,4.8) ellipse (2.2cm and 1.10cm);}
\end{scope}
}
\only<16->{
\node[draw,align=center,minimum height=1.3cm,anchor=south east,font=\scriptsize] at (5,3.5) {
Graph\\$G = (V,E)$\\\includegraphics[width=0.5cm]{build/roadmap-2d-simple}
};
}
% draw edge eval box
\only<1-2>{
\node[draw,align=center,anchor=south west] at (7,3.5)
{\\Edge Weight\\$x : E \rightarrow \mathbb{R}^+$\\};
}
\only<3-15>{
\begin{scope}[font=\tiny]
\node[draw,align=center,anchor=south west] at (7,3.5)
{\\Edge Weight\\$x : E \rightarrow \mathbb{R}^+$\\};
\end{scope}
}
\only<16->{
\node[draw,align=center,anchor=south west,inner sep=1cm] at (7,3.5)
{\\Edge Weight\\$x : E \rightarrow \mathbb{R}^+$\\};
}
\draw[->,line width=1pt] (4,3.25) -- (4,2.75);
\draw[->,line width=1pt] (8,3.25) -- (8,2.75);
\node[draw,align=center,minimum height=1.0cm,minimum width=5cm,anchor=north,
fill=blue!20,rounded corners]
at (6,2.5) {\\$GS(G,x)$};
% clocks
\only<2-13>{
% graph
\node[fill=white,circle,inner sep=-2pt] at (5,3.5) {\LARGE%
\only<2-6>{\showclock{0}{0}}%
\only< 7>{\showclock{0}{10}}%
\only< 8>{\showclock{0}{20}}%
\only< 9>{\showclock{0}{30}}%
\only<10>{\showclock{0}{40}}%
\only<11>{\showclock{0}{50}}%
\only<12>{\showclock{1}{00}}%
\only<13>{\showclock{1}{10}}%
};
% edge weight
\node[fill=white,circle,inner sep=-2pt] at (7,3.5) {\LARGE%
\only<2-6>{\showclock{0}{0}}%
\only< 7>{\showclock{0}{5}}%
\only< 8>{\showclock{0}{10}}%
\only< 9>{\showclock{0}{15}}%
\only<10>{\showclock{0}{20}}%
\only<11>{\showclock{0}{25}}%
\only<12>{\showclock{0}{30}}%
\only<13>{\showclock{0}{35}}%
};
% graph search
\node[fill=white,circle,inner sep=-2pt] at (6,2.5) {\LARGE%
\only<2-6>{\showclock{0}{0}}%
\only< 7>{\showclock{0}{5}}%
\only< 8>{\showclock{0}{10}}%
\only< 9>{\showclock{0}{20}}%
\only<10>{\showclock{0}{40}}%
\only<11>{\showclock{1}{20}}%
\only<12>{\showclock{2}{40}}%
\only<13>{\showclock{5}{20}}%
};
}
\only<14>{
% graph
\node[fill=green,circle,inner sep=-2pt] at (5,3.5) {\LARGE\showclock{1}{10}};
% edge weight
\node[fill=white,circle,inner sep=-2pt] at (7,3.5) {\LARGE\showclock{0}{35}};
% graph search
\node[fill=white,circle,inner sep=-2pt] at (6,2.5) {\LARGE\showclock{5}{20}};
}
\only<15-18>{
% graph
\node[fill=white,circle,inner sep=-2pt] at (5,3.5) {\LARGE\showclock{0}{0}};
% edge weight
\node[fill=white,circle,inner sep=-2pt] at (7,3.5) {\LARGE\showclock{0}{0}};
% graph search
\node[fill=white,circle,inner sep=-2pt] at (6,2.5) {\LARGE\showclock{0}{0}};
}
\only<19->{
% graph
\node[fill=white,circle,inner sep=-2pt] at (5,3.5) {\LARGE\showclock{0}{0}};
% edge weight
\node[fill=green,circle,inner sep=-2pt] at (7,3.5) {\LARGE\showclock{0}{0}};
% graph search
\node[fill=white,circle,inner sep=-2pt] at (6,2.5) {\LARGE\showclock{0}{0}};
}
\node[draw,align=center,shape=document] at (1.5,2) {Query\;\;\;};
\draw[->,line width=1pt] (2.5,2) -- (3.25,2);
\draw[->,line width=1pt] (8.75,2) -- (9.50,2);
\node[draw,align=center,shape=document] at (10.15,2) {$\pi^*$\;\;\;};
\only<14>{
\node at (6,0.75) {A* is {\bf optimally efficient} w.r.t
the number of {\bf vertices considered}.};
}
\only<19>{
\node at (6,0.75) {A* is {\bf not optimally efficient} w.r.t
the number of {\bf edges evaluated}.
};
}
\only<20>{
\node[align=center] at (6,0.75) {
{\bf E$^4$}: \emph{Explicit graphs with Expensive Edge Evaluations}
};
}
\only<18>{
\node at (6,0.5) {\begin{minipage}{11.5cm}\scriptsize{
$^\dag$\PaperPortrait\; Kavraki, Svestka, Latombe, Overmars.
Probabilistic roadmaps for path planning in high-dimensional configuration spaces.
IEEE Transactions on Robotics and Automation, 1996.
}\end{minipage}};
}
\end{tikzpicture}
\end{frame}
\begin{frame}
\frametitle{Explicit Graphs with Expensive Edge Evaluations}
\begin{tikzpicture}
\draw[step=1,black!15,very thin,opacity=\gridopacity] (0,0) grid (12,8);
\node[inner sep=0] at (9.25,5) {%
\includegraphics{build/talk-act1-2d,astara}%
};
% f(x) highlight
\node[inner sep=0pt,fill=black!15,minimum height=2.8cm,minimum width=6.3cm,rounded corners]
at (3.25,6.3) {};
\only<2>{
\fill[green!30] (0.1,5.85) rectangle (6.4,6.7);
\fill[red!30] (0.1,5.0) rectangle (6.4,5.5);
}
% bfs
\node[anchor=north west,inner sep=0pt] at (0.25,7.6) {Best-first search over paths:};
\node[anchor=north,inner sep=0pt] at (3.25,7.0) {\begin{minipage}{6.5cm}\small{
\algrenewcommand\algorithmicindent{0.2cm}%
\begin{algorithmic}
\Loop%
\State ${\hat \pi}^* \leftarrow \argmin\limits_{\pi \in \Pi}
\left[ \hat{f}_x(\pi) \right]$
\State $e \leftarrow$ select from ${\hat \pi}^*$
\State $\mbox{evaluate } x(e)$
\EndLoop
\end{algorithmic}
}\end{minipage}};
\only<3>{
% fx(pi) execution path cost
\node[anchor=north,inner sep=0pt] at (3.25,5.1) {\begin{minipage}{6cm}\small{
\begin{equation*}
\arraycolsep=1.4pt
\hat{f}_x(\pi) = \sum_{e \in \pi} \left\{
\begin{array}{cl}
x(e) & \mbox{if edge } e \mbox{ evaluated} \\
\hat{x}(e) & \mbox{otherwise} \\
\end{array}
\right.
\end{equation*}
}\end{minipage}};
% ensemble highlight
\node[anchor=north,shape=document,draw,inner sep=0.25cm] at (6,2.25) {\begin{minipage}{8.5cm}\small{
Effort model:
$x(e)$ : edge evaluation function \emph{(expensive to compute)}
${\hat x}(e)$ : optimistic estimate of value of $x(e)$
}\end{minipage}};
}
\only<1-2>{
\node at (6,0.5) {\begin{minipage}{11.5cm}\scriptsize{
\PaperPortrait\; Bohlin, Kavraki.
``Path planning using Lazy PRM,'' ICRA, 2000.
}\end{minipage}};
}
%\only<2>{
% \node[fill=white,opacity=0.9] at (9.25,3) {This is Lazy PRM! Animate!};
%}
\end{tikzpicture}
\end{frame}
\begin{frame}
\frametitle{Survey of Graph Search Algorithms}
\begin{tikzpicture}
\draw[step=1,black!15,very thin,opacity=\gridopacity] (0,0) grid (12,8);
\node[align=center,fill=black!15,minimum width=4.8cm,rounded corners]
at (4.85,7.25) {BFS over Vertices\\(implicit graphs)};
\node[align=center,fill=black!15,minimum width=3cm,rounded corners]
at (9.5,7.25) {BFS over Paths\\(explicit graphs)};
%\draw[dashed] (7.5,7.75) -- (7.5,1.25);
%\draw[dashed,->] (7.5,1.5) -- (8.5,1.5);
%\node[align=center,font=\scriptsize]
% at (9.5,1.5) {Expressiveness\\of objective};
% x axis
\draw[->,thick] (1.5,6.5) -- (11.5,6.5);
\node[align=center,font=\scriptsize]
at (10.75,6) {Considers\\edge evaluations};
%\node[font=\small] at (1,7) {Heuristics:};
% y axis
%\draw[->,thick] (2.2,7) -- (2.2,2);
%\node[align=center,font=\scriptsize]
% at (2.2,1.5) {Expressiveness\\of heuristics};
%\node[align=center,fill=black!15,rounded corners,minimum width=1.8cm,minimum height=0.4cm]
% at (1,5.9) {none};
%\node[fill=black!15,rounded corners,minimum height=0.8cm,minimum width=2.8cm]
% at (4,5.9) {Dijkstra's};
%\node[align=center,fill=black!15,rounded corners,minimum width=1.8cm,minimum height=0.4cm]
% at (1,4.9) {${\hat x}$};
\node[fill=black!15,rounded corners,minimum height=0.8cm,minimum width=2.8cm]
at (4,4.9) {A*};
%\node[fill=black!15,rounded corners,minimum height=0.8cm,font=\scriptsize,align=center]
% at (6.5,4.9) {(E)PEA*\\OGA*};
\node[fill=black!15,rounded corners,minimum height=0.8cm,minimum width=2.8cm]
at (9.5,4.9) {Lazy PRM};
%\node[align=center,fill=black!15,rounded corners,minimum width=1.8cm,minimum height=0.4cm]
% at (1,3.9) {${\hat x}, {\hat p} \propto {\hat x}$};
%\node[fill=black!15,rounded corners,minimum height=0.8cm,minimum width=2.8cm]
% at (4,3.9) {Weighted A*};
%\node[align=center,fill=black!15,rounded corners,minimum width=1.8cm,minimum height=0.4cm]
% at (1,2.9) {${\hat x}, {\hat p}$};
%\node[fill=black!15,rounded corners,minimum height=0.8cm,minimum width=2.8cm]
% at (4,2.9) {BUGSY};
%\node[fill=blue!20,rounded corners,minimum height=0.8cm,minimum width=2.8cm]
% at (9.5,2.9) {E$^8$};
\only<1>{
\node at (6,0.5) {\begin{minipage}{11.5cm}\scriptsize{
\PaperPortrait\; Hart, Nilsson, Raphael.,
``A Formal Basis for the Heuristic Determination of Minimum Cost Paths.''
IEEE Transactions on Systems Science and Cybernetics, 1968.
}\end{minipage}};
}
\end{tikzpicture}
\end{frame}
\begin{frame}
\frametitle{Advantages of Best-First Search over Paths}
Advantages of BFS over Paths (e.g. the Lazy PRM):
\begin{itemize}
\item<2-> Naturally minimizes number of evaluated edges
\item<3-> Allows for more flexible path evaluation strategies
\begin{center}
\begin{tikzpicture}
\draw[step=1,black!15,very thin,opacity=0] (0,0) grid (8,2);
\only<28>{\node[inner sep=0pt,rounded corners,fill=blue!20,
minimum width=2.7cm,minimum height=1.7cm] at (1.5,1) {};}
\only<4>\fill[black!50] (0.5,0.5) circle (0.25cm);
\only<6>\fill[black!50] (1.5,0.5) circle (0.25cm);
\only<8>\fill[black!50] (2.5,0.5) circle (0.25cm);
\only<10>\draw[black!50,line width=5pt] (0.5,0.5) -- (2.5,0.5);
\draw[dashed]
(1.5,0.5) -- (1.5,1.5) -- (0.5,1.5) -- (0.5,0.5) -- (2.5,0.5)
-- (2.5,1.5) -- (1.5,1.5);
\only<5-8>{\draw[very thick] (0.5,1.5) -- (0.5,0.5) -- (1.5,0.5);}
\only<7-8>{\draw[very thick] (1.5,1.5) -- (1.5,0.5) -- (2.5,0.5);}
\only<11->{\draw[very thick] (0.5,0.5) -- (2.5,0.5);}
\node[draw,circle,inner sep=2pt,ultra thick,fill=red!50] at (0.5,0.5) {};
\node[draw,circle,inner sep=2pt,ultra thick,fill=green!50] at (2.5,0.5) {};
\fill[black]
(0.5,1.5) circle (0.07cm)
(1.5,0.5) circle (0.07cm)
(1.5,1.5) circle (0.07cm)
(2.5,1.5) circle (0.07cm);
\only<22>\draw[black!50,line width=5pt] (4.5,0.5) -- (7.5,0.5);
\only<24>\draw[black!50,line width=5pt]
(4.5,0.5) -- (5.5,1.5) -- (6.5,1.5) -- (7.5,0.5);
\fill[black] (5.9,0.0) rectangle (6.1,0.9);
\draw[dashed] (4.5,0.5) -- (7.5,0.5) -- (6.5,1.5) -- (5.5,1.5) -- (4.5,0.5);
\only<13-20>{\draw[very thick] (5.5,1.5) -- (4.5,0.5) -- (5.5,0.5);}
\only<15-20,23->{\draw[very thick,red] (5.5,0.5) -- (6.5,0.5);}
\only<17-20>{\draw[very thick] (5.5,1.5) -- (6.5,1.5);}
\only<19-20>{\draw[very thick] (6.5,1.5) -- (7.5,0.5);}
\only<25->\draw[very thick]
(4.5,0.5) -- (5.5,1.5) -- (6.5,1.5) -- (7.5,0.5);
\node[draw,circle,inner sep=2pt,ultra thick,fill=red!50] at (4.5,0.5) {};
\node[draw,circle,inner sep=2pt,ultra thick,fill=green!50] at (7.5,0.5) {};
\fill[black]
(5.5,0.5) circle (0.07cm)
(6.5,0.5) circle (0.07cm)
(5.5,1.5) circle (0.07cm)
(6.5,1.5) circle (0.07cm);
\only<12>\fill[black!50] (4.5,0.5) circle (0.25cm);
\only<14>\fill[black!50] (5.5,0.5) circle (0.25cm);
\only<16>\fill[black!50] (5.5,1.5) circle (0.25cm);
\only<18>\fill[black!50] (6.5,1.5) circle (0.25cm);
\only<20>\fill[black!50] (7.5,0.5) circle (0.25cm);
\end{tikzpicture}
\end{center}
\item<26-> Admits more natural expression of our path objective
\begin{center}
\begin{tikzpicture}
\node[anchor=west,inner xsep=0pt,fill=black!15,minimum height=2cm,rounded corners]
at (0,6.75) {\begin{minipage}{3.25cm}\small{
\algrenewcommand\algorithmicindent{0.0cm}%
\algrenewcommand\algorithmicloop{\!\!\!\!\textbf{loop}}
\begin{algorithmic}
\Loop%
\State $\pi^* \leftarrow \argmin\limits_{\pi \in \Pi} f(\pi)$
\State \textsc{EvalPath}$(\pi^*)$
\EndLoop
\end{algorithmic}
}\end{minipage}};
\end{tikzpicture}
\end{center}
\item<27-> Extends naturally to multi-query regime
\end{itemize}
\end{frame}
\begin{frame}
\frametitle{Survey of Graph Search Algorithms}
\begin{tikzpicture}
\draw[step=1,black!15,very thin,opacity=\gridopacity] (0,0) grid (12,8);
\node[align=center,fill=black!15,minimum width=4.8cm,rounded corners]
at (4.85,7.25) {BFS over Vertices\\(implicit graphs)};
\node[align=center,fill=black!15,minimum width=3cm,rounded corners]
at (9.5,7.25) {BFS over Paths\\(explicit graphs)};
\only<3>{
\draw[dashed] (7.6,7.75) -- (7.6,1.25);
\draw[dashed,->] (7.6,1.5) -- (8.5,1.5);
\node[align=center,font=\scriptsize]
at (9.7,1.9) {Flexibility of\\evaluation order};
\node[align=center,font=\scriptsize]
at (9.7,1.1) {Expressiveness\\of objective};
}
% x axis
\draw[->,thick] (1.5,6.5) -- (11.5,6.5);
\node[align=center,font=\scriptsize]
at (10.75,6) {Considers\\edge evaluations};
%\node[font=\small] at (1,7) {Heuristics:};
% y axis
%\draw[->,thick] (2.2,7) -- (2.2,2);
%\node[align=center,font=\scriptsize]
% at (2.2,1.5) {Expressiveness\\of heuristics};
%\node[align=center,fill=black!15,rounded corners,minimum width=1.8cm,minimum height=0.4cm]
% at (1,5.9) {none};
%\node[fill=black!15,rounded corners,minimum height=0.8cm,minimum width=2.8cm]
% at (4,5.9) {Dijkstra's};
%\node[align=center,fill=black!15,rounded corners,minimum width=1.8cm,minimum height=0.4cm]
% at (1,4.9) {${\hat x}$};
\node[fill=black!15,rounded corners,minimum height=0.8cm,minimum width=2.8cm]
at (4,4.9) {A*};
\only<2>{\node[fill=blue!20,rounded corners,minimum height=0.8cm,font=\scriptsize,align=center]
at (6.5,4.9) {(E)PEA*\\OGA*};}
\only<3>{\node[fill=black!15,rounded corners,minimum height=0.8cm,font=\scriptsize,align=center]
at (6.5,4.9) {(E)PEA*\\OGA*};}
\node[fill=black!15,rounded corners,minimum height=0.8cm,minimum width=2.8cm]
at (9.5,4.9) {Lazy PRM};
%\node[align=center,fill=black!15,rounded corners,minimum width=1.8cm,minimum height=0.4cm]
% at (1,3.9) {${\hat x}, {\hat p} \propto {\hat x}$};
%\node[fill=black!15,rounded corners,minimum height=0.8cm,minimum width=2.8cm]
% at (4,3.9) {Weighted A*};
%\node[align=center,fill=black!15,rounded corners,minimum width=1.8cm,minimum height=0.4cm]
% at (1,2.9) {${\hat x}, {\hat p}$};
%\node[fill=black!15,rounded corners,minimum height=0.8cm,minimum width=2.8cm]
% at (4,2.9) {BUGSY};
%\node[fill=blue!20,rounded corners,minimum height=0.8cm,minimum width=2.8cm]
% at (9.5,2.9) {E$^8$};
\only<2>{
\node at (6,2.1) {\begin{minipage}{11.5cm}\scriptsize{
\PaperPortrait\; Yoshizumi, Teruhisa Miura, Toru Ishida.
``A* with Partial Expansion for Large Branching Factor Problems.'' AAAI 2000.
}\end{minipage}};
\node at (6,1.3) {\begin{minipage}{11.5cm}\scriptsize{
\PaperPortrait\; Felner, Goldenberg, Sharon, Stern, Beja, Sturtevant, Schaeffer, Holte.
``Partial-Expansion A* with Selective Node Generation.'' AAAI 2012.
}\end{minipage}};
\node at (6,0.5) {\begin{minipage}{11.5cm}\scriptsize{
\PaperPortrait\; Goldenberg, Felner, Sturtevant, Holte, Schaeffer.
``Optimal-Generation Variants of EPEA*''. SOCS 2013.
}\end{minipage}};
}
\end{tikzpicture}
\end{frame}
\begin{frame}
\frametitle{Challenge 1: The Planning/Execution Tradeoff}
\begin{tikzpicture}
\draw[step=1,black!15,very thin,opacity=\gridopacity] (0,0) grid (12,8);
\node[inner sep=0pt] at (3.5,5.5) {\includegraphics[width=4cm]{figs/fridge-intro.png}};
\node[inner sep=0pt,anchor=north] at (3.5,4.0)
{\begin{minipage}{4cm}\centering
Autonomous maniptulation tasks
(plan then execute)
\end{minipage}};
\node[inner sep=0pt] at (8.5,5.0) {\includegraphics{build/ensemble-effort-plot-1}};
%\only<2->
%{
% \node[fill=blue!20,rounded corners,align=center] at (6,1.5)
% {
% Key Insight: Optimize for combined\\
% planning \& execution effort \emph{explicitly}!
% };
%}
\end{tikzpicture}
\end{frame}
\begin{frame}
\frametitle{Survey of Graph Search Algorithms}
\begin{tikzpicture}
\draw[step=1,black!15,very thin,opacity=\gridopacity] (0,0) grid (12,8);
\node[align=center,fill=black!15,minimum width=4.8cm,rounded corners]
at (4.85,7.25) {BFS over Vertices\\(implicit graphs)};
\node[align=center,fill=black!15,minimum width=3cm,rounded corners]
at (9.5,7.25) {BFS over Paths\\(explicit graphs)};
\draw[dashed] (7.6,7.75) -- (7.6,1.25);
\draw[dashed,->] (7.6,1.5) -- (8.5,1.5);
\node[align=center,font=\scriptsize]
at (9.7,1.9) {Flexibility of\\evaluation order};
\node[align=center,font=\scriptsize]
at (9.7,1.1) {Expressiveness\\of objective};
% x axis
\draw[->,thick] (1.5,6.5) -- (11.5,6.5);
\node[align=center,font=\scriptsize]
at (10.75,6) {Considers\\edge evaluations};
\only<2->{\node[font=\small] at (1,7) {Heuristics:};}
% y axis
\only<2-4>{\draw[thick] (2.2,7) -- (2.2,2);}
\only<5->{
\draw[->,thick] (2.2,7) -- (2.2,2);
\node[align=center,font=\scriptsize]
at (2.2,1.5) {Expressiveness\\of heuristics};
}
\only<4->{
\node[align=center,fill=black!15,rounded corners,minimum width=1.8cm,minimum height=0.4cm]
at (1,5.9) {none};
\node[fill=black!15,rounded corners,minimum height=0.8cm,minimum width=2.8cm]
at (4,5.9) {Dijkstra's};
}
\only<3->{
\node[align=center,fill=black!15,rounded corners,minimum width=1.8cm,minimum height=0.4cm]
at (1,4.9) {${\hat x}$};
}
\node[fill=black!15,rounded corners,minimum height=0.8cm,minimum width=2.8cm]
at (4,4.9) {A*};
\node[fill=black!15,rounded corners,minimum height=0.8cm,font=\scriptsize,align=center]
at (6.5,4.9) {(E)PEA*\\OGA*};
\node[fill=black!15,rounded corners,minimum height=0.8cm,minimum width=2.8cm]
at (9.5,4.9) {Lazy PRM};
%\node[align=center,fill=black!15,rounded corners,minimum width=1.8cm,minimum height=0.4cm]
% at (1,3.9) {${\hat x}, {\hat p} \propto {\hat x}$};
%\node[fill=black!15,rounded corners,minimum height=0.8cm,minimum width=2.8cm]
% at (4,3.9) {Weighted A*};
\only<6->{
\node[align=center,fill=black!15,rounded corners,minimum width=1.8cm,minimum height=0.4cm]
at (1,2.9) {${\hat x}, {\hat p}$};
}
\only<7->{
\node[fill=black!15,rounded corners,minimum height=0.8cm,minimum width=2.8cm]
at (4,2.9) {BUGSY$^\dag$};
}
%\node[fill=blue!20,rounded corners,minimum height=0.8cm,minimum width=2.8cm]
% at (9.5,2.9) {E$^8$};
\only<8->{
\draw[->,thick] (9.5,4.25) -- (9.5,3.5);
};
\only<9->{
\draw[->,thick] (5.5,2.9) -- (9,2.9);
};
\only<10->{
\node[] at (9.5,2.9) {\large ?};
};
\only<7->{
\node at (5,0.5) {\begin{minipage}{9cm}\scriptsize{
$^\dag$\PaperPortrait\; W. Ruml and M. B. Do. Best-first Utility-Guided Search.\\
International Joint Conference on Artificial Intelligence, 2007.
}\end{minipage}};
}
\end{tikzpicture}
\end{frame}
\begin{frame}
\frametitle{Explicit Graphs with Expensive Edge Evaluations}
\begin{tikzpicture}
\draw[step=1,black!15,very thin,opacity=\gridopacity] (0,0) grid (12,8);
\node[inner sep=0] at (9.25,5) {%
\includegraphics{build/talk-act1-2d,astara}%
};
% f(x) highlight
\node[inner sep=0pt,fill=black!15,minimum height=2.8cm,minimum width=6.3cm,rounded corners]
at (3.25,6.3) {};
\only<4-6>{\fill[green!30] (2.65,5.9) rectangle (6.4,6.7);}
% bfs
\node[anchor=north west,inner sep=0pt] at (0.25,7.6) {Best-first search over paths:};
\node[anchor=north,inner sep=0pt] at (3.25,7.0) {\begin{minipage}{6.5cm}\small{
\algrenewcommand\algorithmicindent{0.2cm}%
\begin{algorithmic}
\Loop%
\only<1-3>{
\State ${\hat \pi}^* \leftarrow \argmin\limits_{\pi \in \Pi}
\left[ \hat{f}_x(\pi) \right]$
}
\only<4-6>{
\State ${\hat \pi}^* \leftarrow \argmin\limits_{\pi \in \Pi}
\left[ (1-\lambda) \hat{f}_x(\pi) + \lambda \hat{f}_p(\pi) \right]$
}
\State $e \leftarrow$ select from ${\hat \pi}^*$
\State $\mbox{evaluate } x(e)$
\EndLoop
\end{algorithmic}
}\end{minipage}};
% fx(pi) execution path cost
\node[anchor=north,inner sep=0pt] at (3.25,5.1) {\begin{minipage}{6cm}\small{
\begin{equation*}
\arraycolsep=1.4pt
\hat{f}_x(\pi) = \sum_{e \in \pi} \left\{
\begin{array}{cl}
x(e) & \mbox{if edge } e \mbox{ evaluated} \\
\hat{x}(e) & \mbox{otherwise} \\
\end{array}
\right.
\end{equation*}
}\end{minipage}};
% fp(pi) execution path cost
\only<3-6>{
\fill[green!30] (0.1,2.5) rectangle (6.4,3.6);
\node[anchor=north,inner sep=0pt] at (3.25,3.9) {\begin{minipage}{6cm}\small{
\begin{equation*}
\arraycolsep=1.4pt
\hat{f}_p(\pi) = \sum_{e \in \pi} \left\{
\begin{array}{cl}
0 & \mbox{if edge } e \mbox{ evaluated} \\
\hat{p}(e) & \mbox{otherwise} \\
\end{array}
\right.
\end{equation*}
}\end{minipage}};
}
% p(e) highlight
\only<2-6>{\fill[green!30] (1.5,0.3) rectangle (10.5,0.8);}
% ensemble highlight
\only<6>{\fill[green!30] (1.6,1.6) rectangle (5.3,2.1);}
\node[anchor=north,shape=document,draw,inner sep=0.25cm] at (6,2.25) {\begin{minipage}{8.5cm}\small{
\only<1-5>{Effort model:}
\only<6>{\emph{Ensemble Effort} model:}
$x(e)$ : edge evaluation function \emph{(expensive to compute)}
${\hat x}(e)$ : optimistic estimate of value of $x(e)$
\only<2-6>{
${\hat p}(e)$ : optimistic estimate of \emph{evaluating} $x(e)$
}
}\end{minipage}};
%\only<5-6>{
% \node[fill=white,opacity=0.9] at (9.25,3) {Animate example!};
%}
\end{tikzpicture}
\end{frame}
\begin{frame}
\frametitle{The E$^8$ Algorithm}
\begin{tikzpicture}
\draw[step=1,black!15,very thin,opacity=\gridopacity] (0,0) grid (12,8);
\node[anchor=north,shape=document,draw,inner sep=0.25cm] at (6,7.75) {\begin{minipage}{8.5cm}\small{
Ensemble Effort model:
$x(e)$ : execution effort function \emph{(expensive to compute)}
${\hat x}(e)$ : optimistic estimate of execution effort for edge $e$
${\hat p}(e)$ : optimistic estimate of planning effort for edge $e$
}\end{minipage}};
\draw[->,line width=1pt] (6,5.5) -- (6,5.0);
% alg
\node[anchor=west,inner xsep=0pt,fill=black!15,minimum height=2cm,rounded corners]
at (0,3.75) {\begin{minipage}{3.25cm}\small{
\algrenewcommand\algorithmicindent{0.0cm}%
\algrenewcommand\algorithmicloop{\!\!\!\!\textbf{loop}}
\begin{algorithmic}
\Loop%
\State $\pi^* \leftarrow \argmin\limits_{\pi \in \Pi} \hat{f}(\pi)$
\State \textsc{EvalPath}$(\pi^*)$
\EndLoop
\end{algorithmic}
}\end{minipage}};
% f(pi) execution path cost
\node[anchor=west,inner xsep=0pt,fill=black!15,minimum height=2cm,rounded corners]
at (3.5,3.75) {\begin{minipage}{8.5cm}\small{%
\vspace{-0.3cm}
\begin{equation*}%
\arraycolsep=1.4pt
\hat{f}(\pi) = \sum_{e \in \pi} \left\{
\begin{array}{cl}
(1-\lambda) x(e) & \mbox{if edge } e \mbox{ evaluated} \\
(1-\lambda) \hat{x}(e) + \lambda \hat{p}(e) & \mbox{otherwise} \\
\end{array}
\right.
\end{equation*}
}\end{minipage}};
\node[inner sep=0pt] at (6,1.5) {\begin{minipage}{12cm}\centering
\emph{Exploiting Ensemble Effort Estimates\\
on Explicit graphs\\
with Expensive Edge Evaluations}
\end{minipage}};
\end{tikzpicture}
\end{frame}
\begin{frame}
\frametitle{Survey of Graph Search Algorithms}
\begin{tikzpicture}
\draw[step=1,black!15,very thin,opacity=\gridopacity] (0,0) grid (12,8);
\node[align=center,fill=black!15,minimum width=4.8cm,rounded corners]
at (4.85,7.25) {BFS over Vertices\\(implicit graphs)};
\node[align=center,fill=black!15,minimum width=3cm,rounded corners]
at (9.5,7.25) {BFS over Paths\\(explicit graphs)};
\draw[dashed] (7.6,7.75) -- (7.6,1.25);
\draw[dashed,->] (7.6,1.5) -- (8.5,1.5);
\node[align=center,font=\scriptsize]
at (9.7,1.9) {Flexibility of\\evaluation order};
\node[align=center,font=\scriptsize]
at (9.7,1.1) {Expressiveness\\of objective};
% x axis
\draw[->,thick] (1.5,6.5) -- (11.5,6.5);
\node[align=center,font=\scriptsize]
at (10.75,6) {Considers\\edge evaluations};
\node[font=\small] at (1,7) {Heuristics:};
% y axis
\draw[->,thick] (2.2,7) -- (2.2,2);
\node[align=center,font=\scriptsize]
at (2.2,1.5) {Expressiveness\\of heuristics};
\node[align=center,fill=black!15,rounded corners,minimum width=1.8cm,minimum height=0.4cm]
at (1,5.9) {none};
\node[fill=black!15,rounded corners,minimum height=0.8cm,minimum width=2.8cm]
at (4,5.9) {Dijkstra's};
\node[align=center,fill=black!15,rounded corners,minimum width=1.8cm,minimum height=0.4cm]
at (1,4.9) {${\hat x}$};
\node[fill=black!15,rounded corners,minimum height=0.8cm,minimum width=2.8cm]
at (4,4.9) {A*};
\node[fill=black!15,rounded corners,minimum height=0.8cm,font=\scriptsize,align=center]
at (6.5,4.9) {(E)PEA*\\OGA*};
\node[fill=black!15,rounded corners,minimum height=0.8cm,minimum width=2.8cm]
at (9.5,4.9) {Lazy PRM};
%\node[align=center,fill=black!15,rounded corners,minimum width=1.8cm,minimum height=0.4cm]
% at (1,3.9) {${\hat x}, {\hat p} \propto {\hat x}$};
%\node[fill=black!15,rounded corners,minimum height=0.8cm,minimum width=2.8cm]
% at (4,3.9) {Weighted A*};
\node[align=center,fill=black!15,rounded corners,minimum width=1.8cm,minimum height=0.4cm]
at (1,2.9) {${\hat x}, {\hat p}$};
\node[fill=black!15,rounded corners,minimum height=0.8cm,minimum width=2.8cm]
at (4,2.9) {BUGSY};
\only<2>{
\node[fill=blue!20,rounded corners,minimum height=0.8cm,minimum width=2.8cm]
at (9.5,2.9) {E$^8$};
}
\end{tikzpicture}
\end{frame}
\begin{frame}
\frametitle{Simplification with Proportional Heuristics}
\begin{tikzpicture}
\draw[step=1,black!15,very thin,opacity=\gridopacity] (0,0) grid (12,8);
% alg
\node[anchor=west,inner xsep=0pt,fill=black!15,minimum height=2cm,rounded corners]
at (0,6.75) {\begin{minipage}{3.25cm}\small{
\algrenewcommand\algorithmicindent{0.0cm}%
\algrenewcommand\algorithmicloop{\!\!\!\!\textbf{loop}}
\begin{algorithmic}
\Loop%
\State $\pi^* \leftarrow \argmin\limits_{\pi \in \Pi} \hat{f}(\pi)$
\State \textsc{EvalPath}$(\pi^*)$
\EndLoop
\end{algorithmic}
}\end{minipage}};
% f(pi) execution path cost
\node[anchor=west,inner xsep=0pt,fill=black!15,minimum height=2cm,rounded corners]
at (3.5,6.75) {\begin{minipage}{8.5cm}\small{%
\vspace{-0.3cm}
\begin{equation*}%
\arraycolsep=1.4pt
\hat{f}(\pi) = \sum_{e \in \pi} \left\{
\begin{array}{cl}
(1-\lambda) x(e) & \mbox{if edge } e \mbox{ evaluated} \\
(1-\lambda) \hat{x}(e) + \lambda \hat{p}(e) & \mbox{otherwise} \\
\end{array}
\right.
\end{equation*}
}\end{minipage}};
\only<2->{
% supposition box
\node[anchor=north,fill=blue!20,rounded corners] at (6,5.5) {\begin{minipage}{9cm}\small{
Suppose ${\hat p}(e) = \alpha {\hat x}(e)$ and $\lambda < 1$.
Then:
\begin{equation*}
\arraycolsep=1.4pt
\hat{f}(\pi) \propto \sum_{e \in \pi} \left\{
\begin{array}{cl}
x(e) & \mbox{if edge } e \mbox{ evaluated} \\