Test circuit, trafficlights: added yellow panel, added pan/tilt

road_description/urdf/circuits/test/ceiling_panels.xacro

 <?xml version="1.0"?>
 <robot name="ceiling" xmlns:xacro="http://www.ros.org/wiki/xacro">
 
+  <xacro:property name="PI" value="3.1415926535897931" />
+  <xacro:property name="pan" value="${PI/4}" />
+  <xacro:property name="tilt" value="${PI/4}" />
+  
   <xacro:include filename="$(find road_description)/urdf/ceiling/panel_macro.xacro" />  
 
   <link name="$(arg parent)"/>
@@ -9,21 +13,28 @@
                parent="$(arg parent)"
                gazebo_material="Gazebo/Red"
                urdf_color="red">
-    <origin xyz="4.0 1.0 $(arg height)" rpy="0 0 0"/>
+    <origin xyz="4.0 1.0 $(arg height)" rpy="${-tilt} 0 ${-pan}"/>
   </xacro:panel>
   
   <xacro:panel name="panel_green" 
                parent="$(arg parent)"
                gazebo_material="Gazebo/Green"
                urdf_color="green">
-    <origin xyz="4.0 -10.0 $(arg height)" rpy="0 0 0"/>
+    <origin xyz="4.0 -10.0 $(arg height)" rpy="${tilt} 0 ${pan}"/>
   </xacro:panel>
   
   <xacro:panel name="panel_blue" 
                parent="$(arg parent)"
                gazebo_material="Gazebo/Blue"
                urdf_color="blue">
-    <origin xyz="-4.0 1.0 $(arg height)" rpy="0 0 0"/>
+    <origin xyz="-4.0 1.0 $(arg height)" rpy="${-tilt} 0 ${pan}"/>
+  </xacro:panel>
+  
+  <xacro:panel name="panel_yellow" 
+               parent="$(arg parent)"
+               gazebo_material="Gazebo/Yellow"
+               urdf_color="yellow">
+    <origin xyz="-4.0 -10.0 $(arg height)" rpy="${tilt} 0 ${-pan}"/>
   </xacro:panel>
 
 </robot>
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