Add mecanum wheels to description package (#6)

* added models for mecanum wheels

Signed-off-by: Aleksander Szymański <bitterisland6@gmail.com>

* added xacro macros for mecanum wheels

Signed-off-by: Aleksander Szymański <bitterisland6@gmail.com>

* added argument for mecanum wheels in robot urdf description

Signed-off-by: Aleksander Szymański <bitterisland6@gmail.com>

* added mecanum_wheels argument in launch file

Signed-off-by: Aleksander Szymański <bitterisland6@gmail.com>

* added wheel outline stl for mecanum wheels

Signed-off-by: Aleksander Szymański <bitterisland6@gmail.com>

* better colision model for mecanum wheels

Signed-off-by: Aleksander Szymański <bitterisland6@gmail.com>

* more informative description of xml argument mecanum_wheels

Signed-off-by: Aleksander Szymański <bitterisland6@gmail.com>

* Add mecanum_wheels param to leo_sim macro

---------

Signed-off-by: Aleksander Szymański <bitterisland6@gmail.com>
Co-authored-by: Błażej Sowa <bsowa123@gmail.com>

leo_description/launch/state_publisher.launch.xml

@@ -3,8 +3,13 @@
     name="model"
     default="$(find-pkg-share leo_description)/urdf/leo.urdf.xacro"
     description="Absolute path to robot urdf.xacro file" />
+
+  <arg 
+    name="mecanum_wheels"
+    default="false"
+    description="Flag specifying wheel types of the robot for visualization purposes"/>
 
   <node pkg="robot_state_publisher" exec="robot_state_publisher">
-    <param name="robot_description" value="$(command 'xacro $(var model)')" />
+    <param name="robot_description" value="$(command 'xacro $(var model) mecanum_wheels:=$(var mecanum_wheels)')" />
   </node>
 </launch>