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[AMR] Add feedback loops
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@@ -4,3 +4,6 @@ $\vec{b}_C$ const bias, $\vec{b}$ time bias, $\mat{M}$ missal., $\vec{n} \sim \c
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\hl{Finding}: Is in $W$-frame: may need $\mat{T}_{BW}$ or $\mat{R}_{BW}$.
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Also see Sec.~\ref{sec:sensors}
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Feedback loop:
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\includegraphics[width=0.6\columnwidth]{assets/loop-main.png}
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@@ -5,7 +5,7 @@
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Model \bi{robot dyn} as \bi{Cont-time non-lin. system of ODE}:\\
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$\dot{\vec{x}} = \vec{f}_C(\vec{x}(t), \vec{u}(t), \vec{w}(t))$, measurement $\vec{z}(t) = \vec{h}(\vec{x}(t)) + \vec{v}(t)$.
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With: $\pardiff{t}\vec{x}(t) = f_C(\vec{x}(t), \vec{u}(t))$ the model for the robot state update and $\vec{h}(\vec{x}(t))$ the model for the measurements (e.g. for IMU)
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With: $\pardiff{t}\vec{x}(t) = \vec{f}_C(\vec{x}(t), \vec{u}(t))$ the model for the robot state update and $\vec{h}(\vec{x}(t))$ the model for the measurements (e.g. for IMU)
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\vspace{0.5mm}
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\hrule
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@@ -1,3 +1,9 @@
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Below feedback loops for PID and LQR
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\includegraphics[width=0.49\columnwidth]{assets/loop-pid.png}
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\includegraphics[width=0.5\columnwidth]{assets/loop-lqr.png}
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\subsection{MPC}
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\bi{Cost function} ($p(\vec{x}_N)$ \textit{terminal cost}, sum the \textit{stage cost})
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\[
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@@ -1,4 +1,3 @@
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\newpage
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\subsubsection{Rapidly-Exploring Random Tree (RRT)}
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\begin{algorithm}
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\small
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@@ -27,6 +26,9 @@
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\EndProcedure
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\end{algorithmic}
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\end{algorithm}
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Notes: \texttt{nearestConfiguration} may be on edge, then edge is split;
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\texttt{stoppingConfiguration} returns furthest config $x_f$ on segment $x_n$ to $x$ that produces collision-free edge $(x_n, x_f)$
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Returns a collision-free path as graph. Need nearest neighbour search.
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Extension to RRT* to make path better:
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\begin{algorithm}
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+3
@@ -26,3 +26,6 @@ $\varepsilon$ is prob. to act randomly, $1 - \varepsilon$ is prob. to act on pol
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Value-based (estimate val or $Q$-func and extract pol., e.g. Q-Learn),
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Actor-Critic (estim. val or $Q$ of curr. pol., improve pol., e.g. A3C, SAC),
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Policy-Gradient (diff. expect. reward w.r.t. params of policy network, e.g. REINFORCE)
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\includegraphics[width=0.5\columnwidth]{assets/loop-rl.png}
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\includegraphics[width=0.5\columnwidth]{assets/loop-drl.png}
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