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clean up doc
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AtsushiSakai committed Nov 17, 2018
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Expand Up @@ -35,10 +35,16 @@
"### MPC modeling\n",
"\n",
"State vector is:\n",
"$$ z = [x, y, v,\\phi]$$ x: x-position, y:y-position, v:velocity, φ: yaw angle\n",
"\n",
"$$ z = [x, y, v,\\phi]$$\n",
"\n",
"x: x-position, y:y-position, v:velocity, φ: yaw angle\n",
"\n",
"Input vector is:\n",
"$$ u = [a, \\delta]$$ a: accellation, δ: steering angle\n",
"\n",
"$$ u = [a, \\delta]$$\n",
"\n",
"a: accellation, δ: steering angle\n",
"\n"
]
},
Expand Down Expand Up @@ -103,9 +109,13 @@
"\n",
"\n",
"Vehicle model is \n",
"\n",
"$$ \\dot{x} = vcos(\\phi)$$\n",
"\n",
"$$ \\dot{y} = vsin((\\phi)$$\n",
"\n",
"$$ \\dot{v} = a$$\n",
"\n",
"$$ \\dot{\\phi} = \\frac{vtan(\\delta)}{L}$$\n",
"\n",
"\n",
Expand All @@ -128,7 +138,7 @@
"source": [
"where\n",
"\n",
"\\begin{equation*}\n",
"$\\begin{equation*}\n",
"A' =\n",
"\\begin{bmatrix}\n",
"\\frac{\\partial }{\\partial x}vcos(\\phi) & \n",
Expand Down Expand Up @@ -156,15 +166,15 @@
"0 & 0 & 0 & 0 \\\\\n",
"0 & 0 &\\frac{tan(\\bar{\\delta})}{L} & 0 \\\\\n",
"\\end{bmatrix}\n",
"\\end{equation*}\n",
"\\end{equation*}$\n",
"\n"
]
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"\\begin{equation*}\n",
"$\\begin{equation*}\n",
"B' =\n",
"\\begin{bmatrix}\n",
"\\frac{\\partial }{\\partial a}vcos(\\phi) &\n",
Expand All @@ -184,7 +194,7 @@
"1 & 0 \\\\\n",
"0 & \\frac{\\bar{v}}{Lcos^2(\\bar{\\delta})} \\\\\n",
"\\end{bmatrix}\n",
"\\end{equation*}\n",
"\\end{equation*}$\n",
"\n"
]
},
Expand Down Expand Up @@ -228,7 +238,7 @@
"cell_type": "markdown",
"metadata": {},
"source": [
"\\begin{equation*}\n",
"$\\begin{equation*}\n",
"B = dtB'\\\\\n",
"=\n",
"\\begin{bmatrix} \n",
Expand All @@ -237,14 +247,14 @@
"dt & 0 \\\\\n",
"0 & \\frac{\\bar{v}}{Lcos^2(\\bar{\\delta})}dt \\\\\n",
"\\end{bmatrix}\n",
"\\end{equation*}"
"\\end{equation*}$"
]
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"\\begin{equation*}\n",
"$\\begin{equation*}\n",
"C = (f(\\bar{z},\\bar{u})-A'\\bar{z}-B'\\bar{u})dt\\\\\n",
"= dt(\n",
"\\begin{bmatrix} \n",
Expand Down Expand Up @@ -275,7 +285,7 @@
"0\\\\\n",
"-\\frac{\\bar{v}\\bar{\\delta}}{Lcos^2(\\bar{\\delta})}dt\\\\\n",
"\\end{bmatrix}\n",
"\\end{equation*}"
"\\end{equation*}$"
]
},
{
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104 changes: 8 additions & 96 deletions docs/modules/Model_predictive_speed_and_steering_control.rst
Expand Up @@ -29,13 +29,13 @@ State vector is:

.. math:: z = [x, y, v,\phi]

\ x: x-position, y:y-position, v:velocity, φ: yaw angle
x: x-position, y:y-position, v:velocity, φ: yaw angle

Input vector is:

.. math:: u = [a, \delta]

\ a: accellation, δ: steering angle
a: accellation, δ: steering angle

The MPC cotroller minimize this cost function for path tracking:

Expand Down Expand Up @@ -94,57 +94,9 @@ ODE is

where

:raw-latex:`\begin{equation*}
A' =
\begin{bmatrix}
\frac{\partial }{\partial x}vcos(\phi) &
\frac{\partial }{\partial y}vcos(\phi) &
\frac{\partial }{\partial v}vcos(\phi) &
\frac{\partial }{\partial \phi}vcos(\phi)\\
\frac{\partial }{\partial x}vsin(\phi) &
\frac{\partial }{\partial y}vsin(\phi) &
\frac{\partial }{\partial v}vsin(\phi) &
\frac{\partial }{\partial \phi}vsin(\phi)\\
\frac{\partial }{\partial x}a&
\frac{\partial }{\partial y}a&
\frac{\partial }{\partial v}a&
\frac{\partial }{\partial \phi}a\\
\frac{\partial }{\partial x}\frac{vtan(\delta)}{L}&
\frac{\partial }{\partial y}\frac{vtan(\delta)}{L}&
\frac{\partial }{\partial v}\frac{vtan(\delta)}{L}&
\frac{\partial }{\partial \phi}\frac{vtan(\delta)}{L}\\
\end{bmatrix}
\\
 =
\begin{bmatrix}
0 & 0 & cos(\bar{\phi}) & -\bar{v}sin(\bar{\phi})\\
0 & 0 & sin(\bar{\phi}) & \bar{v}cos(\bar{\phi}) \\
0 & 0 & 0 & 0 \\
0 & 0 &\frac{tan(\bar{\delta})}{L} & 0 \\
\end{bmatrix}
\end{equation*}`

:raw-latex:`\begin{equation*}
B' =
\begin{bmatrix}
\frac{\partial }{\partial a}vcos(\phi) &
\frac{\partial }{\partial \delta}vcos(\phi)\\
\frac{\partial }{\partial a}vsin(\phi) &
\frac{\partial }{\partial \delta}vsin(\phi)\\
\frac{\partial }{\partial a}a &
\frac{\partial }{\partial \delta}a\\
\frac{\partial }{\partial a}\frac{vtan(\delta)}{L} &
\frac{\partial }{\partial \delta}\frac{vtan(\delta)}{L}\\
\end{bmatrix}
\\
 =
\begin{bmatrix}
0 & 0 \\
0 & 0 \\
1 & 0 \\
0 & \frac{\bar{v}}{Lcos^2(\bar{\delta})} \\
\end{bmatrix}
\end{equation*}`
:math:`\begin{equation*} A' = \begin{bmatrix} \frac{\partial }{\partial x}vcos(\phi) & \frac{\partial }{\partial y}vcos(\phi) & \frac{\partial }{\partial v}vcos(\phi) & \frac{\partial }{\partial \phi}vcos(\phi)\\ \frac{\partial }{\partial x}vsin(\phi) & \frac{\partial }{\partial y}vsin(\phi) & \frac{\partial }{\partial v}vsin(\phi) & \frac{\partial }{\partial \phi}vsin(\phi)\\ \frac{\partial }{\partial x}a& \frac{\partial }{\partial y}a& \frac{\partial }{\partial v}a& \frac{\partial }{\partial \phi}a\\ \frac{\partial }{\partial x}\frac{vtan(\delta)}{L}& \frac{\partial }{\partial y}\frac{vtan(\delta)}{L}& \frac{\partial }{\partial v}\frac{vtan(\delta)}{L}& \frac{\partial }{\partial \phi}\frac{vtan(\delta)}{L}\\ \end{bmatrix} \\  = \begin{bmatrix} 0 & 0 & cos(\bar{\phi}) & -\bar{v}sin(\bar{\phi})\\ 0 & 0 & sin(\bar{\phi}) & \bar{v}cos(\bar{\phi}) \\ 0 & 0 & 0 & 0 \\ 0 & 0 &\frac{tan(\bar{\delta})}{L} & 0 \\ \end{bmatrix} \end{equation*}`

:math:`\begin{equation*} B' = \begin{bmatrix} \frac{\partial }{\partial a}vcos(\phi) & \frac{\partial }{\partial \delta}vcos(\phi)\\ \frac{\partial }{\partial a}vsin(\phi) & \frac{\partial }{\partial \delta}vsin(\phi)\\ \frac{\partial }{\partial a}a & \frac{\partial }{\partial \delta}a\\ \frac{\partial }{\partial a}\frac{vtan(\delta)}{L} & \frac{\partial }{\partial \delta}\frac{vtan(\delta)}{L}\\ \end{bmatrix} \\  = \begin{bmatrix} 0 & 0 \\ 0 & 0 \\ 1 & 0 \\ 0 & \frac{\bar{v}}{Lcos^2(\bar{\delta})} \\ \end{bmatrix} \end{equation*}`

You can get a discrete-time mode with Forward Euler Discretization with
sampling time dt.
Expand All @@ -165,49 +117,9 @@ where,

:math:`\begin{equation*} A = (I + dtA')\\ = \begin{bmatrix} 1 & 0 & cos(\bar{\phi})dt & -\bar{v}sin(\bar{\phi})dt\\ 0 & 1 & sin(\bar{\phi})dt & \bar{v}cos(\bar{\phi})dt \\ 0 & 0 & 1 & 0 \\ 0 & 0 &\frac{tan(\bar{\delta})}{L}dt & 1 \\ \end{bmatrix} \end{equation*}`

:raw-latex:`\begin{equation*}
B = dtB'\\
=
\begin{bmatrix}
0 & 0 \\
0 & 0 \\
dt & 0 \\
0 & \frac{\bar{v}}{Lcos^2(\bar{\delta})}dt \\
\end{bmatrix}
\end{equation*}`

:raw-latex:`\begin{equation*}
C = (f(\bar{z},\bar{u})-A'\bar{z}-B'\bar{u})dt\\
= dt(
\begin{bmatrix}
\bar{v}cos(\bar{\phi})\\
\bar{v}sin(\bar{\phi}) \\
\bar{a}\\
\frac{\bar{v}tan(\bar{\delta})}{L}\\
\end{bmatrix}
-
\begin{bmatrix}
\bar{v}cos(\bar{\phi})-\bar{v}sin(\bar{\phi})\bar{\phi}\\
\bar{v}sin(\bar{\phi})+\bar{v}cos(\bar{\phi})\bar{\phi}\\
0\\
\frac{\bar{v}tan(\bar{\delta})}{L}\\
\end{bmatrix}
-
\begin{bmatrix}
0\\
0 \\
\bar{a}\\
\frac{\bar{v}\bar{\delta}}{Lcos^2(\bar{\delta})}\\
\end{bmatrix}
)\\
=
\begin{bmatrix}
\bar{v}sin(\bar{\phi})\bar{\phi}dt\\
-\bar{v}cos(\bar{\phi})\bar{\phi}dt\\
0\\
-\frac{\bar{v}\bar{\delta}}{Lcos^2(\bar{\delta})}dt\\
\end{bmatrix}
\end{equation*}`
:math:`\begin{equation*} B = dtB'\\ = \begin{bmatrix} 0 & 0 \\ 0 & 0 \\ dt & 0 \\ 0 & \frac{\bar{v}}{Lcos^2(\bar{\delta})}dt \\ \end{bmatrix} \end{equation*}`

:math:`\begin{equation*} C = (f(\bar{z},\bar{u})-A'\bar{z}-B'\bar{u})dt\\ = dt( \begin{bmatrix} \bar{v}cos(\bar{\phi})\\ \bar{v}sin(\bar{\phi}) \\ \bar{a}\\ \frac{\bar{v}tan(\bar{\delta})}{L}\\ \end{bmatrix} - \begin{bmatrix} \bar{v}cos(\bar{\phi})-\bar{v}sin(\bar{\phi})\bar{\phi}\\ \bar{v}sin(\bar{\phi})+\bar{v}cos(\bar{\phi})\bar{\phi}\\ 0\\ \frac{\bar{v}tan(\bar{\delta})}{L}\\ \end{bmatrix} - \begin{bmatrix} 0\\ 0 \\ \bar{a}\\ \frac{\bar{v}\bar{\delta}}{Lcos^2(\bar{\delta})}\\ \end{bmatrix} )\\ = \begin{bmatrix} \bar{v}sin(\bar{\phi})\bar{\phi}dt\\ -\bar{v}cos(\bar{\phi})\bar{\phi}dt\\ 0\\ -\frac{\bar{v}\bar{\delta}}{Lcos^2(\bar{\delta})}dt\\ \end{bmatrix} \end{equation*}`

This equation is implemented at

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