Changes between Version 10 and Version 11 of doc/tec/mas

Timestamp:

Aug 30, 2018 9:30:10 AM (6 years ago)

Author:

sward

Comment:

--

doc/tec/mas

@@ -23 +23 @@
 
 '''Creating the visibility graph'''\\\\
-A tool separate from PALM has been developed to calculate the visibility graph. It is a standalone Fortran program (find it at {{{UTIL/agent_preprocessing/agent_preprocessing.f90}}}). \\
-
-1) Navigate to the {{{INPUT}}}-folder of your JOB.\\
+A tool separate from PALM (Agent Preprocessing Tool for PALM - APT-P) has been developed to calculate the visibility graph. It is a standalone Fortran program (find it at {{{UTIL/agent_preprocessing/agent_preprocessing.f90}}}). \\
+To use it,
+1) navigate to the {{{INPUT}}}-folder of your JOB.\\
 2) Make sure your Input folder contains the relevant topography information in either an ASCII- or NetCDF-file ([wiki:doc/app/iofiles/pids#topo see here]).\\
 3) Make sure your Input folder contains the {{{_p3d}}}-file. In it, if necessary, specify the namelist {{{&prepro_par}}} with the parameters [#flag_2d flag_2d], [#internal_buildings internal_buildings] and [#tolerance_dp tolerance_dp].\\
-4) Execute the program by typing
+4) Execute the APT-P by typing
 {{{
 agent_preprocessing
@@ -78 +78 @@
 \end{equation*}
 }}}
-In the MAS, //U_0// is [wiki:/doc/app/agtpar#repuls_wall repuls_wall] and //R_B// is [wiki:/doc/app/agtpar#sigma_rep_wall sigma_rep_wall].\\\\
+In the MAS, //U,,0,,// is [wiki:/doc/app/agtpar#repuls_wall repuls_wall] and //R,,B,,// is [wiki:/doc/app/agtpar#sigma_rep_wall sigma_rep_wall].\\\\
 The repulsion by another **pedestrian //β//** is defined as
 {{{
@@ -93 +93 @@
 \end{equation*}
 }}}
-In the MAS, //U_0// is [wiki:/doc/app/agtpar#repuls_wall repuls_wall] and //R// is [wiki:/doc/app/agtpar#sigma_rep_wall sigma_rep_wall].\\
+In the MAS, //V,,0,,// is [wiki:/doc/app/agtpar#repuls_agent repuls_agent] and //R,,β,,// is [wiki:/doc/app/agtpar#sigma_rep_agent sigma_rep_agent]. This agent repulsive force is only used if α and β are already colliding (i.e. two circles with centers at the respective agents' position with radius [wiki:/doc/app/agtpar#radius_agent radius_agent] are intersecting). Otherwise, a collision avoidance force according to ([#karamouzas2014 Karamouzas et. al, 2014]) is calculated:
+{{{
+#!Latex
+\begin{equation*}
+\vec{F}_{\alpha} = -\nabla_{\vec{r}_{\alpha \beta}} \left( \frac{k}{\tau^2}e^{-\tau/\tau_0} \right).
+\end{equation*}
+}}}
+Here, τ is the time until, given the current trajectory, a collision between the two pedestrians would occur, τ,,0,, = 3 s and k is a constant to sets the units with a value of 1.5 m^2^ kg.\\\\
+The **acceleration force** 
+{{{
+#!Latex
+\begin{equation*}
+\vec{F_a} = \frac{}{}(v_0\vec{e}_{\alpha} - \vec{v}_{\alpha})
+\end{equation*}
+}}}
+describes the tendency of a pedestrian to accelerate toward its target. Here, τ,,α,, is a relaxation time ([wiki:/doc/app/agtpar#tau_accel_agent tau_accel_agent]) that describes how quickly the pedestrian approaches v,,0,, its desired walking speed with the direction to its current target, e.\\\\
+The pedestrian's walking speed is given by
+{{{
+#!Latex
+\begin{equation*}
+\frac{d\vec{v}_{\alpha}}{dt} = \vec{F}_{\alpha},
+\end{equation*}
+}}}
+with a simple Euler-forward method used for time-integration.
+
+\\
 
 
@@ -169 +194 @@
 This algorithm recursively approximates a polygon section as a straight line connecting the end points of that section. If the greatest distance between this line and any vertex between the end points is smaller than '''tolerance_dp''', the approximation is accepted and all vertices in between are deleted. Otherwise, the segment is split into two segments at the vertex of greatest distance and the process is repeated.\\\\
 '''tolerance_dp''' is internally multiplied with {{{SQRT( dx*dy )}}}. If a building is left with less than 4 vertices after simplification using '''tolerance_dp(0)''', it is reset and the process is repeated with '''tolerance_dp(1)''', then '''tolerance_dp(2)''', if necessary.\\\\
-'''NOTE:''' The NavMesh-tool produces an ASCII output-file {{{topo.txt}}}. The polygon data is stored in this file. After execution of the tool, please check the polygon representation. If you are not satisfied, adjust '''tolerance_dp''' and rerun the tool.
+'''NOTE:''' The APT-P produces an ASCII output-file {{{topo.txt}}}. The polygon data is stored in this file. After execution of the tool, please check the polygon representation. If you are not satisfied, adjust '''tolerance_dp''' and rerun the tool.
 }}}