updated xacro files

urdf/pan_tilt_example.xacro

+<?xml version="1.0"?>
+
+<robot name="pan_tilt" xmlns:xacro="http://www.ros.org/wiki/xacro">
+
+  <xacro:include filename="$(find iri_dynamixel_pan_tilt_description)/urdf/pan_tilt.xacro"/>
+  <xacro:property name="xacro_config_file" value="$(find iri_dynamixel_pan_tilt_description)/config/pan_tilt_xacro.yaml"/>
+  <xacro:property name="xacro_properties" value="${load_yaml(xacro_config_file)}"/>
+
+  <link name="${xacro_properties['parent']}"/>
+
+  <link name="${xacro_properties['load_name']}">
+    <visual>
+      <geometry>
+        <box size=".05 .05 .01"/>
+      </geometry>
+      <origin rpy="0 ${pi/2} 0" xyz="0 0 .025"/>
+      <material name="blue">
+        <color rgba="0 0 .8 1"/>
+      </material>
+    </visual>
+    <inertial>
+      <origin rpy="0 ${pi/2} 0" xyz="0 0 .025"/>
+      <mass value="1"/>
+      <inertia 
+        ixx="0.0001" ixy="0.0" ixz="0.0" 
+        iyy="0.0001" iyz="0.0" 
+        izz="0.0001"/>
+    </inertial>
+  </link>
+
+  <link name="camera_optical_frame"/>
+
+  <gazebo reference="${xacro_properties['load_name']}">
+    <mu1>0.2</mu1>
+    <mu2>0.2</mu2>
+    <material>Gazebo/Blue</material>
+  </gazebo>
+
+  <joint name="${xacro_properties['load_name']}_to_camera_optical_frame" type="fixed" >
+    <parent link="${xacro_properties['load_name']}"/>
+    <child link="camera_optical_frame"/>
+    <origin xyz="0.0 0.0 0.025" rpy="${pi/2} 0 -${pi/2}"/>
+  </joint>
+
+  <xacro:pan_tilt parent="${xacro_properties['parent']}" pan_joint_name="${xacro_properties['pan_joint_name']}" tilt_joint_name="${xacro_properties['tilt_joint_name']}" load_name="${xacro_properties['load_name']}" joint_interface="${xacro_properties['joint_interface']}" sim_config="$(find iri_dynamixel_pan_tilt_gazebo)/config/pan_tilt_gazebo_config.yaml">
+    <origin xyz="0.0 0.0 0.0" rpy="0 0 0" />
+  </xacro:pan_tilt>
+
+</robot>
+