<?xml version="1.0" ?>
<sdf version="1.4">
  <world name="default">
    <physics type="ode">
      <gravity>0.0 0.0 -10.0</gravity>
      <ode>
        <solver>
          <type>quick</type>
          <iters>50</iters>
          <sor>0.8</sor>
        </solver>
        <constraints>
          <cfm>0.0</cfm>
          <erp>0.2</erp>
          <contact_max_correcting_vel>0.1</contact_max_correcting_vel>
          <contact_surface_layer>0.0</contact_surface_layer>
        </constraints>
      </ode>
      <real_time_update_rate>0</real_time_update_rate>
      <max_step_size>0.001</max_step_size>
    </physics>
    <include>
      <uri>model://sun</uri>
    </include>

    <model name="ground_plane">
      <static>true</static>
      <link name="link">
        <collision name="collision">
          <geometry>
            <plane>
              <normal>0 0 1</normal>
              <size>1000 1000</size>
            </plane>
          </geometry>
          <surface>
            <friction>
              <ode>
                <mu>1</mu>
                <mu2>1</mu2>
              </ode>
            </friction>
          </surface>
        </collision>
        <visual name="visual">
          <cast_shadows>false</cast_shadows>
          <geometry>
            <plane>
              <normal>0 0 1</normal>
              <size>1000 1000</size>
            </plane>
          </geometry>
          <material>
            <script>
              <uri>file://media/materials/scripts/gazebo.material</uri>
              <name>Gazebo/Grey</name>
            </script>
          </material>
        </visual>
      </link>
    </model>

    <model name="lift_drag_demo_model">
      <pose>0 0 0 0 0 0</pose>
      <static>false</static>
      <link name="body_1">
        <pose>1.75 0 0.1 0 0 0</pose>
        <inertial>
          <pose>0.0 0.0 0.0 0.0 0.0 0.0</pose>
          <inertia>
            <ixx>1.8</ixx>
            <ixy>0.0</ixy>
            <ixz>0.0</ixz>
            <iyy>10.8</iyy>
            <iyz>0.0</iyz>
            <izz>10.8</izz>
          </inertia>
          <mass>10.0</mass>
        </inertial>
        <collision name="collision">
          <geometry>
            <box>
              <size>3.6 0.2 0.2</size>
            </box>
          </geometry>
          <surface>
            <friction>
              <ode>
                <mu>0.1</mu>
                <mu2>0.1</mu2>
              </ode>
            </friction>
          </surface>
        </collision>
        <visual name="visual">
          <geometry>
            <box>
              <size>3.6 0.2 0.2</size>
            </box>
          </geometry>
          <material>
            <ambient>0.2 0.2 0.2 1.0</ambient>
            <diffuse>.421 0.225 0.0 1.0</diffuse>
          </material>
        </visual>
        <sensor name='imu_sensor' type='imu'>
          <always_on>1</always_on>
          <update_rate>1000</update_rate>
          <imu>
            <angular_velocity>
              <x>
                <noise type="gaussian">
                 <mean>0</mean>
                 <stddev>0.0002</stddev>
                 <bias_mean>7.5e-06</bias_mean>
                 <bias_stddev>8e-07</bias_stddev>
                </noise>
              </x>
              <y>
                <noise type="gaussian">
                 <mean>0</mean>
                 <stddev>0.0002</stddev>
                 <bias_mean>7.5e-06</bias_mean>
                 <bias_stddev>8e-07</bias_stddev>
                </noise>
              </y>
              <z>
                <noise type="gaussian">
                 <mean>0</mean>
                 <stddev>0.0002</stddev>
                 <bias_mean>7.5e-06</bias_mean>
                 <bias_stddev>8e-07</bias_stddev>
                </noise>
              </z>
            </angular_velocity>

            <linear_acceleration>
              <x>
                <noise type="gaussian">
                  <mean>0</mean>
                  <stddev>0.017</stddev>
                  <bias_mean>0.1</bias_mean>
                  <bias_stddev>0.001</bias_stddev>
                </noise>
              </x>
              <y>
                <noise type="gaussian">
                  <mean>0</mean>
                  <stddev>0.017</stddev>
                  <bias_mean>0.1</bias_mean>
                  <bias_stddev>0.001</bias_stddev>
                </noise>
              </y>
              <z>
                <noise type="gaussian">
                  <mean>0</mean>
                  <stddev>0.017</stddev>
                  <bias_mean>0.1</bias_mean>
                  <bias_stddev>0.001</bias_stddev>
                </noise>
              </z>
            </linear_acceleration>
          </imu>
          <pose>0 0 0 0 0 0</pose>
        </sensor>
      </link>
      <link name="rod_1">
        <pose>0 0 0.24 0 0 0</pose>
        <inertial>
          <pose>0.0 0.0 0 0.0 0.0 0.0</pose>
          <inertia>
            <ixx>0.012</ixx>
            <ixy>0.0</ixy>
            <ixz>0.0</ixz>
            <iyy>0.012</iyy>
            <iyz>0.0</iyz>
            <izz>0.0012</izz>
          </inertia>
          <mass>1.0</mass>
        </inertial>
        <collision name="collision">
          <geometry>
            <box>
              <size>0.02 0.02 0.08</size>
            </box>
          </geometry>
        </collision>
        <visual name="visual">
          <geometry>
            <box>
              <size>0.02 0.02 0.08</size>
            </box>
          </geometry>
          <material>
            <ambient>0.3 0.3 0.3 1.0</ambient>
            <diffuse>.421 0.225 0.0 1.0</diffuse>
          </material>
        </visual>
      </link>
      <link name="blade_1">
        <pose>0 0 0.28 0 0 0</pose>
        <inertial>
          <pose>0.0 0.25 0 0.0 0.0 0.0</pose>
          <inertia>
            <ixx>0.0000465</ixx>
            <ixy>0.0</ixy>
            <ixz>0.0</ixz>
            <iyy>0.0000006</iyy>
            <iyz>0.0</iyz>
            <izz>0.0000470</izz>
          </inertia>
          <mass>0.01</mass>
        </inertial>
        <collision name="collision">
          <pose>0.0 0.5 0 0.0 0.0 0.0</pose>
          <geometry>
            <box>
              <size>0.2 1.0 0.01</size>
            </box>
          </geometry>
        </collision>
        <visual name="visual">
          <pose>0.0 0.5 0 0.0 0.0 0.0</pose>
          <geometry>
            <box>
              <size>0.2 1.0 0.01</size>
            </box>
          </geometry>
          <material>
            <ambient>0.5 0.2 0.2 1.0</ambient>
            <diffuse>.421 0.225 0.0 1.0</diffuse>
          </material>
        </visual>
      </link>
      <link name="blade_2">
        <pose>0 0 0.28 0 0 3.141593</pose>
        <inertial>
          <pose>0.0 0.25 0 0.0 0.0 0.0</pose>
          <inertia>
            <ixx>0.0000465</ixx>
            <ixy>0.0</ixy>
            <ixz>0.0</ixz>
            <iyy>0.0000006</iyy>
            <iyz>0.0</iyz>
            <izz>0.0000470</izz>
          </inertia>
          <mass>0.01</mass>
        </inertial>
        <collision name="collision">
          <pose>0.0 0.5 0 0.0 0.0 0.0</pose>
          <geometry>
            <box>
              <size>0.2 1.0 0.01</size>
            </box>
          </geometry>
        </collision>
        <visual name="visual">
          <pose>0.0 0.5 0 0.0 0.0 0</pose>
          <geometry>
            <box>
              <size>0.2 1.0 0.01</size>
            </box>
          </geometry>
          <material>
            <ambient>0.2 0.5 0.2 1.0</ambient>
            <diffuse>.421 0.225 0.0 1.0</diffuse>
          </material>
        </visual>
      </link>
      <joint name="rod_1_joint" type="revolute">
        <parent>body_1</parent>
        <child>rod_1</child>
        <pose>0.0 0.0 0.0 0.0 0.0 0.0</pose>
        <axis>
          <limit>
            <lower>-1e16</lower>
            <upper>1e16</upper>
          </limit>
          <xyz>0.0 0.0 -1.0</xyz>
          <dynamics>
            <damping>0.0001</damping>
          </dynamics>
        </axis>
        <physics>
          <ode>
            <cfm_damping>1</cfm_damping>
          </ode>
        </physics>
      </joint>
      <joint name="blade_1_joint" type="revolute">
        <parent>rod_1</parent>
        <child>blade_1</child>
        <pose>0.0 0.0 0.0 0.0 0.0 0.0</pose>
        <axis>
          <limit>
            <lower>-0.0</lower>
            <upper>0.0</upper>
          </limit>
          <xyz>1.0 0.0 0.0</xyz>
          <dynamics>
            <damping>1.000000</damping>
          </dynamics>
        </axis>
        <physics>
          <ode>
            <limit>
              <cfm>0.004</cfm>
              <erp>0.2</erp>
            </limit>
            <cfm_damping>1</cfm_damping>
          </ode>
        </physics>
      </joint>
      <joint name="blade_2_joint" type="revolute">
        <parent>rod_1</parent>
        <child>blade_2</child>
        <pose>0.0 0.0 0.0 0.0 0.0 0.0</pose>
        <axis>
          <limit>
            <lower>-0.0</lower>
            <upper>0.0</upper>
          </limit>
          <xyz>-1.0 0.0 0.0</xyz>
          <dynamics>
            <damping>1.000000</damping>
          </dynamics>
        </axis>
        <physics>
          <ode>
            <limit>
              <cfm>0.004</cfm>
              <erp>0.2</erp>
            </limit>
            <cfm_damping>1</cfm_damping>
          </ode>
        </physics>
      </joint>

      <link name="rod_2">
        <pose>3.5 0 0.24 0 0 0</pose>
        <inertial>
          <pose>0.0 0.0 0 0.0 0.0 0.0</pose>
          <inertia>
            <ixx>0.012</ixx>
            <ixy>0.0</ixy>
            <ixz>0.0</ixz>
            <iyy>0.012</iyy>
            <iyz>0.0</iyz>
            <izz>0.0012</izz>
          </inertia>
          <mass>1.0</mass>
        </inertial>
        <collision name="collision">
          <geometry>
            <box>
              <size>0.02 0.02 0.08</size>
            </box>
          </geometry>
        </collision>
        <visual name="visual">
          <geometry>
            <box>
              <size>0.02 0.02 0.08</size>
            </box>
          </geometry>
          <material>
            <ambient>0.3 0.3 0.3 1.0</ambient>
            <diffuse>.421 0.225 0.0 1.0</diffuse>
          </material>
        </visual>
      </link>
      <link name="blade_3">
        <pose>3.5 0 0.28 0 0 0</pose>
        <inertial>
          <pose>0.0 0.25 0 0.0 0.0 0.0</pose>
          <inertia>
            <ixx>0.0000465</ixx>
            <ixy>0.0</ixy>
            <ixz>0.0</ixz>
            <iyy>0.0000006</iyy>
            <iyz>0.0</iyz>
            <izz>0.0000470</izz>
          </inertia>
          <mass>0.01</mass>
        </inertial>
        <collision name="collision">
          <pose>0.0 0.5 0 0.0 0.0 0.0</pose>
          <geometry>
            <box>
              <size>0.2 1.0 0.01</size>
            </box>
          </geometry>
        </collision>
        <visual name="visual">
          <pose>0.0 0.5 0 0.0 0.0 0.0</pose>
          <geometry>
            <box>
              <size>0.2 1.0 0.01</size>
            </box>
          </geometry>
          <material>
            <ambient>0.5 0.2 0.2 1.0</ambient>
            <diffuse>.421 0.225 0.0 1.0</diffuse>
          </material>
        </visual>
      </link>
      <link name="blade_4">
        <pose>3.5 0 0.28 0 0 3.141593</pose>
        <inertial>
          <pose>0.0 0.25 0 0.0 0.0 0.0</pose>
          <inertia>
            <ixx>0.0000465</ixx>
            <ixy>0.0</ixy>
            <ixz>0.0</ixz>
            <iyy>0.0000006</iyy>
            <iyz>0.0</iyz>
            <izz>0.0000470</izz>
          </inertia>
          <mass>0.01</mass>
        </inertial>
        <collision name="collision">
          <pose>0.0 0.5 0 0.0 0.0 0.0</pose>
          <geometry>
            <box>
              <size>0.2 1.0 0.01</size>
            </box>
          </geometry>
        </collision>
        <visual name="visual">
          <pose>0.0 0.5 0 0.0 0.0 0</pose>
          <geometry>
            <box>
              <size>0.2 1.0 0.01</size>
            </box>
          </geometry>
          <material>
            <ambient>0.2 0.5 0.2 1.0</ambient>
            <diffuse>.421 0.225 0.0 1.0</diffuse>
          </material>
        </visual>
      </link>
      <joint name="rod_2_joint" type="revolute">
        <parent>body_1</parent>
        <child>rod_2</child>
        <pose>0.0 0.0 0.0 0.0 0.0 0.0</pose>
        <axis>
          <limit>
            <lower>-1e16</lower>
            <upper>1e16</upper>
          </limit>
          <xyz>0.0 0.0 1.0</xyz>
          <dynamics>
            <damping>0.0001</damping>
          </dynamics>
        </axis>
        <physics>
          <ode>
            <cfm_damping>1</cfm_damping>
          </ode>
        </physics>
      </joint>
      <joint name="blade_3_joint" type="revolute">
        <parent>rod_2</parent>
        <child>blade_3</child>
        <pose>0.0 0.0 0.0 0.0 0.0 0.0</pose>
        <axis>
          <limit>
            <lower>-0.0</lower>
            <upper>0.0</upper>
          </limit>
          <xyz>1.0 0.0 0.0</xyz>
          <dynamics>
            <damping>1.000000</damping>
          </dynamics>
        </axis>
        <physics>
          <ode>
            <limit>
              <cfm>0.004</cfm>
              <erp>0.2</erp>
            </limit>
            <cfm_damping>1</cfm_damping>
          </ode>
        </physics>
      </joint>
      <joint name="blade_4_joint" type="revolute">
        <parent>rod_2</parent>
        <child>blade_4</child>
        <pose>0.0 0.0 0.0 0.0 0.0 0.0</pose>
        <axis>
          <limit>
            <lower>-0.0</lower>
            <upper>0.0</upper>
          </limit>
          <xyz>1.0 0.0 0.0</xyz>
          <dynamics>
            <damping>1.000000</damping>
          </dynamics>
        </axis>
        <physics>
          <ode>
            <limit>
              <cfm>0.004</cfm>
              <erp>0.2</erp>
            </limit>
            <cfm_damping>1</cfm_damping>
          </ode>
        </physics>
      </joint>
      <!-- -->
      <joint name="gear_joint_1" type="gearbox">
          <parent>rod_1</parent>
          <child>rod_2</child>
          <gearbox_ratio>1.0</gearbox_ratio>
          <gearbox_reference_body>body_1</gearbox_reference_body>
          <axis>
            <xyz>0.000000 0.000000 1.000000</xyz>
          </axis>
          <axis2>
            <xyz>0.000000 0.000000 1.000000</xyz>
          </axis2>
      </joint>

      <plugin name="gazebo_blade_1" filename="libLiftDragPlugin.so">
        <a0>0.1</a0>
        <cla>0.100</cla>
        <cda>0.01</cda>
        <cma>0.00</cma>
        <alpha_stall>0.2</alpha_stall>
        <cla_stall>-0.2</cla_stall>
        <cda_stall>1.0</cda_stall>
        <cma_stall>0.0</cma_stall>
        <cp>0.0 0.5 0</cp>
        <area>0.2</area>
        <air_density>1.2041</air_density>
        <forward>1 0 0</forward>
        <upward>0 0 1</upward>
        <link_name>lift_drag_demo_model::blade_1</link_name>
      </plugin>
      <plugin name="gazebo_blade_2" filename="libLiftDragPlugin.so">
        <a0>0.1</a0>
        <cla>0.100</cla>
        <cda>0.01</cda>
        <cma>0.00</cma>
        <alpha_stall>0.2</alpha_stall>
        <cla_stall>-0.2</cla_stall>
        <cda_stall>1.0</cda_stall>
        <cma_stall>0.0</cma_stall>
        <cp>0.0 0.5 0</cp>
        <area>0.2</area>
        <air_density>1.2041</air_density>
        <forward>1 0 0</forward>
        <upward>0 0 1</upward>
        <link_name>lift_drag_demo_model::blade_2</link_name>
      </plugin>
      <plugin name="gazebo_blade_3" filename="libLiftDragPlugin.so">
        <a0>0.1</a0>
        <cla>0.100</cla>
        <cda>0.01</cda>
        <cma>0.00</cma>
        <alpha_stall>0.2</alpha_stall>
        <cla_stall>-0.2</cla_stall>
        <cda_stall>1.0</cda_stall>
        <cma_stall>0.0</cma_stall>
        <cp>0.0 0.5 0</cp>
        <area>0.2</area>
        <air_density>1.2041</air_density>
        <forward>-1 0 0</forward>
        <upward>0 0 1</upward>
        <link_name>lift_drag_demo_model::blade_3</link_name>
      </plugin>
      <plugin name="gazebo_blade_4" filename="libLiftDragPlugin.so">
        <a0>0.1</a0>
        <cla>0.100</cla>
        <cda>0.01</cda>
        <cma>0.00</cma>
        <alpha_stall>0.2</alpha_stall>
        <cla_stall>-0.2</cla_stall>
        <cda_stall>1.0</cda_stall>
        <cma_stall>0.0</cma_stall>
        <cp>0.0 0.5 0</cp>
        <area>0.2</area>
        <air_density>1.2041</air_density>
        <forward>-1 0 0</forward>
        <upward>0 0 1</upward>
        <link_name>lift_drag_demo_model::blade_4</link_name>
      </plugin>



      <link name="body_2">
        <pose>1.75 0 0.1 0 0 0</pose>
        <inertial>
          <pose>0.0 0.0 0.0 0.0 0.0 0.0</pose>
          <inertia>
            <ixx>10.8</ixx>
            <ixy>0.0</ixy>
            <ixz>0.0</ixz>
            <iyy>1.8</iyy>
            <iyz>0.0</iyz>
            <izz>10.8</izz>
          </inertia>
          <mass>10.0</mass>
        </inertial>
        <collision name="collision">
          <geometry>
            <box>
              <size>0.2 3.6 0.2</size>
            </box>
          </geometry>
          <surface>
            <friction>
              <ode>
                <mu>0.1</mu>
                <mu2>0.1</mu2>
              </ode>
            </friction>
          </surface>
        </collision>
        <visual name="visual">
          <geometry>
            <box>
              <size>0.2 3.6 0.2</size>
            </box>
          </geometry>
          <material>
            <ambient>0.2 0.2 0.2 1.0</ambient>
            <diffuse>.421 0.225 0.0 1.0</diffuse>
          </material>
        </visual>
      </link>
      <link name="rod_3">
        <pose>1.75 -1.75 0.24 0 0 0</pose>
        <inertial>
          <pose>0.0 0.0 0 0.0 0.0 0.0</pose>
          <inertia>
            <ixx>0.012</ixx>
            <ixy>0.0</ixy>
            <ixz>0.0</ixz>
            <iyy>0.012</iyy>
            <iyz>0.0</iyz>
            <izz>0.0012</izz>
          </inertia>
          <mass>1.0</mass>
        </inertial>
        <collision name="collision">
          <geometry>
            <box>
              <size>0.02 0.02 0.08</size>
            </box>
          </geometry>
        </collision>
        <visual name="visual">
          <geometry>
            <box>
              <size>0.02 0.02 0.08</size>
            </box>
          </geometry>
          <material>
            <ambient>0.3 0.3 0.3 1.0</ambient>
            <diffuse>.421 0.225 0.0 1.0</diffuse>
          </material>
        </visual>
      </link>
      <link name="blade_5">
        <pose>1.75 -1.75 0.28 0 0 0</pose>
        <inertial>
          <pose>0.0 0.25 0 0.0 0.0 0.0</pose>
          <inertia>
            <ixx>0.0000465</ixx>
            <ixy>0.0</ixy>
            <ixz>0.0</ixz>
            <iyy>0.0000006</iyy>
            <iyz>0.0</iyz>
            <izz>0.0000470</izz>
          </inertia>
          <mass>0.01</mass>
        </inertial>
        <collision name="collision">
          <pose>0.0 0.5 0 0.0 0.0 0.0</pose>
          <geometry>
            <box>
              <size>0.2 1.0 0.01</size>
            </box>
          </geometry>
        </collision>
        <visual name="visual">
          <pose>0.0 0.5 0 0.0 0.0 0.0</pose>
          <geometry>
            <box>
              <size>0.2 1.0 0.01</size>
            </box>
          </geometry>
          <material>
            <ambient>0.5 0.2 0.2 1.0</ambient>
            <diffuse>.421 0.225 0.0 1.0</diffuse>
          </material>
        </visual>
      </link>
      <link name="blade_6">
        <pose>1.75 -1.75 0.28 0 0 3.141593</pose>
        <inertial>
          <pose>0.0 0.25 0 0.0 0.0 0.0</pose>
          <inertia>
            <ixx>0.0000465</ixx>
            <ixy>0.0</ixy>
            <ixz>0.0</ixz>
            <iyy>0.0000006</iyy>
            <iyz>0.0</iyz>
            <izz>0.0000470</izz>
          </inertia>
          <mass>0.01</mass>
        </inertial>
        <collision name="collision">
          <pose>0.0 0.5 0 0.0 0.0 0.0</pose>
          <geometry>
            <box>
              <size>0.2 1.0 0.01</size>
            </box>
          </geometry>
        </collision>
        <visual name="visual">
          <pose>0.0 0.5 0 0.0 0.0 0</pose>
          <geometry>
            <box>
              <size>0.2 1.0 0.01</size>
            </box>
          </geometry>
          <material>
            <ambient>0.2 0.5 0.2 1.0</ambient>
            <diffuse>.421 0.225 0.0 1.0</diffuse>
          </material>
        </visual>
      </link>
      <joint name="rod_3_joint" type="revolute">
        <parent>body_2</parent>
        <child>rod_3</child>
        <pose>0.0 0.0 0.0 0.0 0.0 0.0</pose>
        <axis>
          <limit>
            <lower>-1e16</lower>
            <upper>1e16</upper>
          </limit>
          <xyz>0.0 0.0 1.0</xyz>
          <dynamics>
            <damping>0.0001</damping>
          </dynamics>
        </axis>
        <physics>
          <ode>
            <cfm_damping>1</cfm_damping>
          </ode>
        </physics>
      </joint>
      <joint name="blade_5_joint" type="revolute">
        <parent>rod_3</parent>
        <child>blade_5</child>
        <pose>0.0 0.0 0.0 0.0 0.0 0.0</pose>
        <axis>
          <limit>
            <lower>-0.0</lower>
            <upper>0.0</upper>
          </limit>
          <xyz>1.0 0.0 0.0</xyz>
          <dynamics>
            <damping>1.000000</damping>
          </dynamics>
        </axis>
        <physics>
          <ode>
            <limit>
              <cfm>0.004</cfm>
              <erp>0.2</erp>
            </limit>
            <cfm_damping>1</cfm_damping>
          </ode>
        </physics>
      </joint>
      <joint name="blade_6_joint" type="revolute">
        <parent>rod_3</parent>
        <child>blade_6</child>
        <pose>0.0 0.0 0.0 0.0 0.0 0.0</pose>
        <axis>
          <limit>
            <lower>-0.0</lower>
            <upper>0.0</upper>
          </limit>
          <xyz>-1.0 0.0 0.0</xyz>
          <dynamics>
            <damping>1.000000</damping>
          </dynamics>
        </axis>
        <physics>
          <ode>
            <limit>
              <cfm>0.004</cfm>
              <erp>0.2</erp>
            </limit>
            <cfm_damping>1</cfm_damping>
          </ode>
        </physics>
      </joint>

      <link name="rod_4">
        <pose>1.75 1.75 0.24 0 0 0</pose>
        <inertial>
          <pose>0.0 0.0 0 0.0 0.0 0.0</pose>
          <inertia>
            <ixx>0.012</ixx>
            <ixy>0.0</ixy>
            <ixz>0.0</ixz>
            <iyy>0.012</iyy>
            <iyz>0.0</iyz>
            <izz>0.0012</izz>
          </inertia>
          <mass>1.0</mass>
        </inertial>
        <collision name="collision">
          <geometry>
            <box>
              <size>0.02 0.02 0.08</size>
            </box>
          </geometry>
        </collision>
        <visual name="visual">
          <geometry>
            <box>
              <size>0.02 0.02 0.08</size>
            </box>
          </geometry>
          <material>
            <ambient>0.3 0.3 0.3 1.0</ambient>
            <diffuse>.421 0.225 0.0 1.0</diffuse>
          </material>
        </visual>
      </link>
      <link name="blade_7">
        <pose>1.75 1.75 0.28 0 0 0</pose>
        <inertial>
          <pose>0.0 0.25 0 0.0 0.0 0.0</pose>
          <inertia>
            <ixx>0.0000465</ixx>
            <ixy>0.0</ixy>
            <ixz>0.0</ixz>
            <iyy>0.0000006</iyy>
            <iyz>0.0</iyz>
            <izz>0.0000470</izz>
          </inertia>
          <mass>0.01</mass>
        </inertial>
        <collision name="collision">
          <pose>0.0 0.5 0 0.0 0.0 0.0</pose>
          <geometry>
            <box>
              <size>0.2 1.0 0.01</size>
            </box>
          </geometry>
        </collision>
        <visual name="visual">
          <pose>0.0 0.5 0 0.0 0.0 0.0</pose>
          <geometry>
            <box>
              <size>0.2 1.0 0.01</size>
            </box>
          </geometry>
          <material>
            <ambient>0.5 0.2 0.2 1.0</ambient>
            <diffuse>.421 0.225 0.0 1.0</diffuse>
          </material>
        </visual>
      </link>
      <link name="blade_8">
        <pose>1.75 1.75 0.28 0 0 3.141593</pose>
        <inertial>
          <pose>0.0 0.25 0 0.0 0.0 0.0</pose>
          <inertia>
            <ixx>0.0000465</ixx>
            <ixy>0.0</ixy>
            <ixz>0.0</ixz>
            <iyy>0.0000006</iyy>
            <iyz>0.0</iyz>
            <izz>0.0000470</izz>
          </inertia>
          <mass>0.01</mass>
        </inertial>
        <collision name="collision">
          <pose>0.0 0.5 0 0.0 0.0 0.0</pose>
          <geometry>
            <box>
              <size>0.2 1.0 0.01</size>
            </box>
          </geometry>
        </collision>
        <visual name="visual">
          <pose>0.0 0.5 0 0.0 0.0 0</pose>
          <geometry>
            <box>
              <size>0.2 1.0 0.01</size>
            </box>
          </geometry>
          <material>
            <ambient>0.2 0.5 0.2 1.0</ambient>
            <diffuse>.421 0.225 0.0 1.0</diffuse>
          </material>
        </visual>
      </link>
      <joint name="body_joint" type="revolute">
        <parent>body_1</parent>
        <child>body_2</child>
        <pose>0.0 0.0 0.0 0.0 0.0 0.0</pose>
        <axis>
          <limit>
            <lower>0</lower>
            <upper>0</upper>
          </limit>
          <xyz>0.0 0.0 1.0</xyz>
          <dynamics>
            <damping>0.0001</damping>
          </dynamics>
        </axis>
        <physics>
          <ode>
            <cfm_damping>1</cfm_damping>
          </ode>
        </physics>
      </joint>
      <joint name="rod_4_joint" type="revolute">
        <parent>body_2</parent>
        <child>rod_4</child>
        <pose>0.0 0.0 0.0 0.0 0.0 0.0</pose>
        <axis>
          <limit>
            <lower>-1e16</lower>
            <upper>1e16</upper>
          </limit>
          <xyz>0.0 0.0 1.0</xyz>
          <dynamics>
            <damping>0.0001</damping>
          </dynamics>
        </axis>
        <physics>
          <ode>
            <cfm_damping>1</cfm_damping>
          </ode>
        </physics>
      </joint>
      <joint name="blade_7_joint" type="revolute">
        <parent>rod_4</parent>
        <child>blade_7</child>
        <pose>0.0 0.0 0.0 0.0 0.0 0.0</pose>
        <axis>
          <limit>
            <lower>-0.0</lower>
            <upper>0.0</upper>
          </limit>
          <xyz>1.0 0.0 0.0</xyz>
          <dynamics>
            <damping>1.000000</damping>
          </dynamics>
        </axis>
        <physics>
          <ode>
            <limit>
              <cfm>0.004</cfm>
              <erp>0.2</erp>
            </limit>
            <cfm_damping>1</cfm_damping>
          </ode>
        </physics>
      </joint>
      <joint name="blade_8_joint" type="revolute">
        <parent>rod_4</parent>
        <child>blade_8</child>
        <pose>0.0 0.0 0.0 0.0 0.0 0.0</pose>
        <axis>
          <limit>
            <lower>-0.0</lower>
            <upper>0.0</upper>
          </limit>
          <xyz>-1.0 0.0 0.0</xyz>
          <dynamics>
            <damping>1.000000</damping>
          </dynamics>
        </axis>
        <physics>
          <ode>
            <limit>
              <cfm>0.004</cfm>
              <erp>0.2</erp>
            </limit>
            <cfm_damping>1</cfm_damping>
          </ode>
        </physics>
      </joint>
      <!-- -->
      <joint name="gear_joint_2" type="gearbox">
          <parent>rod_3</parent>
          <child>rod_4</child>
          <gearbox_ratio>-1.0</gearbox_ratio>
          <gearbox_reference_body>body_2</gearbox_reference_body>
          <axis>
            <xyz>0.000000 0.000000 1.000000</xyz>
          </axis>
          <axis2>
            <xyz>0.000000 0.000000 1.000000</xyz>
          </axis2>
      </joint>

      <plugin name="gazebo_blade_5" filename="libLiftDragPlugin.so">
        <a0>0.1</a0>
        <cla>0.100</cla>
        <cda>0.01</cda>
        <cma>0.00</cma>
        <alpha_stall>0.2</alpha_stall>
        <cla_stall>-0.2</cla_stall>
        <cda_stall>1.0</cda_stall>
        <cma_stall>0.0</cma_stall>
        <cp>0.0 0.5 0</cp>
        <area>0.2</area>
        <air_density>1.2041</air_density>
        <forward>-1 0 0</forward>
        <upward>0 0 1</upward>
        <link_name>lift_drag_demo_model::blade_5</link_name>
      </plugin>
      <plugin name="gazebo_blade_6" filename="libLiftDragPlugin.so">
        <a0>0.1</a0>
        <cla>0.100</cla>
        <cda>0.01</cda>
        <cma>0.00</cma>
        <alpha_stall>0.2</alpha_stall>
        <cla_stall>-0.2</cla_stall>
        <cda_stall>1.0</cda_stall>
        <cma_stall>0.0</cma_stall>
        <cp>0.0 0.5 0</cp>
        <area>0.2</area>
        <air_density>1.2041</air_density>
        <forward>-1 0 0</forward>
        <upward>0 0 1</upward>
        <link_name>lift_drag_demo_model::blade_6</link_name>
      </plugin>
      <plugin name="gazebo_blade_7" filename="libLiftDragPlugin.so">
        <a0>0.1</a0>
        <cla>0.100</cla>
        <cda>0.01</cda>
        <cma>0.00</cma>
        <alpha_stall>0.2</alpha_stall>
        <cla_stall>-0.2</cla_stall>
        <cda_stall>1.0</cda_stall>
        <cma_stall>0.0</cma_stall>
        <cp>0.0 0.5 0</cp>
        <area>0.2</area>
        <air_density>1.2041</air_density>
        <forward>-1 0 0</forward>
        <upward>0 0 1</upward>
        <link_name>lift_drag_demo_model::blade_7</link_name>
      </plugin>
      <plugin name="gazebo_blade_8" filename="libLiftDragPlugin.so">
        <a0>0.1</a0>
        <cla>0.100</cla>
        <cda>0.01</cda>
        <cma>0.00</cma>
        <alpha_stall>0.2</alpha_stall>
        <cla_stall>-0.2</cla_stall>
        <cda_stall>1.0</cda_stall>
        <cma_stall>0.0</cma_stall>
        <cp>0.0 0.5 0</cp>
        <area>0.2</area>
        <air_density>1.2041</air_density>
        <forward>-1 0 0</forward>
        <upward>0 0 1</upward>
        <link_name>lift_drag_demo_model::blade_8</link_name>
      </plugin>

    </model>
  </world>
</sdf>
