[Mini Quadrotor][Gazebo] create a world where there is an April tag o…

…n the ground

robots/mini_quadrotor/gazebo_model/world/simple_april_tags.world

@@ -0,0 +1,45 @@
+<?xml version="1.0" ?>
+<sdf version='1.4'>
+  <world name='default'>
+
+    <physics type='ode'>
+      <max_step_size>0.001</max_step_size>
+      <real_time_factor>1</real_time_factor>
+      <real_time_update_rate>1000</real_time_update_rate>
+      <gravity>0 0 -9.8</gravity>
+    </physics>
+
+    <spherical_coordinates>
+      <surface_model>EARTH_WGS84</surface_model>
+      <latitude_deg>0</latitude_deg>
+      <longitude_deg>0</longitude_deg>
+      <elevation>0</elevation>
+      <heading_deg>0</heading_deg>
+    </spherical_coordinates>
+
+    <!-- A global light source -->
+   <scene>
+      <sky>
+        <clouds>
+          <speed>12</speed>
+        </clouds>
+      </sky>
+   </scene>
+
+    <include>
+      <uri>model://sun</uri>
+    </include>
+
+    <include>
+      <uri>model://ground_plane</uri>
+    </include>
+
+    <model name="april_tag1" >
+      <pose>0.0 0.0 0.0 0 0 0</pose>
+      <include>
+        <uri>model://Apriltag36_11_00000_small//</uri>
+      </include>
+    </model>
+
+  </world>
+</sdf>

robots/mini_quadrotor/launch/bringup.launch

@@ -8,7 +8,7 @@
   <arg name="estimate_mode"  default= "0" />
   <arg name="sim_estimate_mode"  default= "2" />
   <arg name="headless" default="True" />
-  <arg name="worldtype" default="$(find aerial_robot_simulation)/gazebo_model/world/empty.world" />
+  <arg name="worldtype" default="$(find mini_quadrotor)/gazebo_model/world/simple_april_tags.world" />
   <arg name="launch_gazebo" default="True" />
   <arg name="direct_model" default="False" />
   <arg name="direct_model_name" />