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                <mu>1.0</mu>
                <mu2>1.0</mu2>
              </ode>
              <torsional>
                <coefficient>1.0</coefficient>
                <patch_radius>2.0</patch_radius>
              </torsional>
            </friction>
          </surface>
        </collision>
        <visual name="visual">
          <geometry>
            <box>
              <size>0.2 0.2 0.2</size>
            </box>
          </geometry>
        </visual>
      </link>
      <plugin name='box_low_cog_5' filename='libInitialVelocityPlugin.so'>
        <linear>0 0 0</linear>
        <angular>0 0 6.283185307179586</angular>
      </plugin>
    </model>


    <model name='pinch_1'>
      <allow_auto_disable>0</allow_auto_disable>
      <pose>1.2043255373859678 6 0.6021627686929839 0 0 0</pose>
      <link name="box">
        <self_collide>true</self_collide>
        <pose>-0.24000000000000005 0 0 0 1.5707963267948966 0</pose>
        <inertial>
          <pose>0 0 0 0 0 0</pose>
          <mass>16.0</mass>
          <inertia>
            <ixx>0.4801333333333334</ixx>
            <iyy>0.48333333333333345</iyy>
            <izz>0.0034666666666666674</izz>
            <ixy>0.0</ixy>
            <ixz>0.0</ixz>
            <iyz>0.0</iyz>
          </inertia>
        </inertial>
        <collision name="collision">
          <geometry>
            <box>
              <size>0.05 0.010000000000000002 0.6000000000000001</size>
            </box>
          </geometry>
          <surface>
            <friction>
              <ode>
                <mu>1000.0</mu>
                <mu2>1000.0</mu2>
              </ode>
              <torsional>
                <coefficient>0.0</coefficient>
                <patch_radius>2.0</patch_radius>
              </torsional>
            </friction>
          </surface>
        </collision>
        <visual name="visual">
          <geometry>
            <box>
              <size>0.05 0.010000000000000002 0.6000000000000001</size>
            </box>
          </geometry>
        </visual>
      </link>
      <link name="sphere_1">
        <pose>0 0.015000000000000003 0 0 0 0</pose>
        <collision name="collision">
          <geometry>
            <sphere>
              <radius>0.010000000000000002</radius>
            </sphere>
          </geometry>
          <surface>
            <friction>
              <ode>
                <mu>1000.0</mu>
                <mu2>1000.0</mu2>
              </ode>
              <torsional>
                <coefficient>0.0</coefficient>
                <patch_radius>2.0</patch_radius>
              </torsional>
            </friction>
          </surface>
        </collision>
        <visual name="visual">
          <geometry>
            <sphere>
              <radius>0.010000000000000002</radius>
            </sphere>
          </geometry>
        </visual>
      </link>
      <link name="sphere_2">
        <pose>0 -0.015000000000000003 0 0 0 0</pose>
        <collision name="collision">
          <geometry>
            <sphere>
              <radius>0.010000000000000002</radius>
            </sphere>
          </geometry>
          <surface>
            <friction>
              <ode>
                <mu>1000.0</mu>
                <mu2>1000.0</mu2>
              </ode>
              <torsional>
                <coefficient>0.0</coefficient>
                <patch_radius>2.0</patch_radius>
              </torsional>
            </friction>
          </surface>
        </collision>
        <visual name="visual">
          <geometry>
            <sphere>
              <radius>0.010000000000000002</radius>
            </sphere>
          </geometry>
        </visual>
      </link>
      <joint name = "joint_1" type="prismatic">
        <parent>world</parent>
        <child>sphere_1</child>
        <axis>
          <xyz>0 -1 0</xyz>
          <dynamics>
            <damping>100</damping>
            <spring_stiffness>1000000</spring_stiffness>
            <spring_reference>0.002</spring_reference>
          </dynamics>
        </axis>
      </joint>
      <joint name = "joint_2" type="prismatic">
        <parent>world</parent>
        <child>sphere_2</child>
        <axis>
          <xyz>0 1 0</xyz>
          <dynamics>
            <damping>100</damping>
            <spring_stiffness>1000000</spring_stiffness>
            <spring_reference>0.002</spring_reference>
          </dynamics>
        </axis>
      </joint>
    </model>

    <model name='pinch_2'>
      <allow_auto_disable>0</allow_auto_disable>
      <pose>2.4086510747719356 6 0.6021627686929839 0 0 0</pose>
      <link name="box">
        <self_collide>true</self_collide>
        <pose>-0.24000000000000005 0 0 0 1.5707963267948966 0</pose>
        <inertial>
          <pose>0 0 0 0 0 0</pose>
          <mass>16.0</mass>
          <inertia>
            <ixx>0.4801333333333334</ixx>
            <iyy>0.48333333333333345</iyy>
            <izz>0.0034666666666666674</izz>
            <ixy>0.0</ixy>
            <ixz>0.0</ixz>
            <iyz>0.0</iyz>
          </inertia>
        </inertial>
        <collision name="collision">
          <geometry>
            <box>
              <size>0.05 0.010000000000000002 0.6000000000000001</size>
            </box>
          </geometry>
          <surface>
            <friction>
              <ode>
                <mu>1000.0</mu>
                <mu2>1000.0</mu2>
              </ode>
              <torsional>
                <coefficient>0.001</coefficient>
                <patch_radius>2.0</patch_radius>
              </torsional>
            </friction>
          </surface>
        </collision>
        <visual name="visual">
          <geometry>
            <box>
              <size>0.05 0.010000000000000002 0.6000000000000001</size>
            </box>
          </geometry>
        </visual>
      </link>
      <link name="sphere_1">
        <pose>0 0.015000000000000003 0 0 0 0</pose>
        <collision name="collision">
          <geometry>
            <sphere>
              <radius>0.010000000000000002</radius>
            </sphere>
          </geometry>
          <surface>
            <friction>
              <ode>
                <mu>1000.0</mu>
                <mu2>1000.0</mu2>
              </ode>
              <torsional>
                <coefficient>0.001</coefficient>
                <patch_radius>2.0</patch_radius>
              </torsional>
            </friction>
          </surface>
        </collision>
        <visual name="visual">
          <geometry>
            <sphere>
              <radius>0.010000000000000002</radius>
            </sphere>
          </geometry>
        </visual>
      </link>
      <link name="sphere_2">
        <pose>0 -0.015000000000000003 0 0 0 0</pose>
        <collision name="collision">
          <geometry>
            <sphere>
              <radius>0.010000000000000002</radius>
            </sphere>
          </geometry>
          <surface>
            <friction>
              <ode>
                <mu>1000.0</mu>
                <mu2>1000.0</mu2>
              </ode>
              <torsional>
                <coefficient>0.001</coefficient>
                <patch_radius>2.0</patch_radius>
              </torsional>
            </friction>
          </surface>
        </collision>
        <visual name="visual">
          <geometry>
            <sphere>
              <radius>0.010000000000000002</radius>
            </sphere>
          </geometry>
        </visual>
      </link>
      <joint name = "joint_1" type="prismatic">
        <parent>world</parent>
        <child>sphere_1</child>
        <axis>
          <xyz>0 -1 0</xyz>
          <dynamics>
            <damping>100</damping>
            <spring_stiffness>1000000</spring_stiffness>
            <spring_reference>0.002</spring_reference>
          </dynamics>
        </axis>
      </joint>
      <joint name = "joint_2" type="prismatic">
        <parent>world</parent>
        <child>sphere_2</child>
        <axis>
          <xyz>0 1 0</xyz>
          <dynamics>
            <damping>100</damping>
            <spring_stiffness>1000000</spring_stiffness>
            <spring_reference>0.002</spring_reference>
          </dynamics>
        </axis>
      </joint>
    </model>

    <model name='pinch_3'>
      <allow_auto_disable>0</allow_auto_disable>
      <pose>3.6129766121579037 6 0.6021627686929839 0 0 0</pose>
      <link name="box">
        <self_collide>true</self_collide>
        <pose>-0.24000000000000005 0 0 0 1.5707963267948966 0</pose>
        <inertial>
          <pose>0 0 0 0 0 0</pose>
          <mass>16.0</mass>
          <inertia>
            <ixx>0.4801333333333334</ixx>
            <iyy>0.48333333333333345</iyy>
            <izz>0.0034666666666666674</izz>
            <ixy>0.0</ixy>
            <ixz>0.0</ixz>
            <iyz>0.0</iyz>
          </inertia>
        </inertial>
        <collision name="collision">
          <geometry>
            <box>
              <size>0.05 0.010000000000000002 0.6000000000000001</size>
            </box>
          </geometry>
          <surface>
            <friction>
              <ode>
                <mu>1000.0</mu>
                <mu2>1000.0</mu2>
              </ode>
              <torsional>
                <coefficient>0.005</coefficient>
                <patch_radius>2.0</patch_radius>
              </torsional>
            </friction>
          </surface>
        </collision>
        <visual name="visual">
          <geometry>
            <box>
              <size>0.05 0.010000000000000002 0.6000000000000001</size>
            </box>
          </geometry>
        </visual>
      </link>
      <link name="sphere_1">
        <pose>0 0.015000000000000003 0 0 0 0</pose>
        <collision name="collision">
          <geometry>
            <sphere>
              <radius>0.010000000000000002</radius>
            </sphere>
          </geometry>
          <surface>
            <friction>
              <ode>
                <mu>1000.0</mu>
                <mu2>1000.0</mu2>
              </ode>
              <torsional>
                <coefficient>0.005</coefficient>
                <patch_radius>2.0</patch_radius>
              </torsional>
            </friction>
          </surface>
        </collision>
        <visual name="visual">
          <geometry>
            <sphere>
              <radius>0.010000000000000002</radius>
            </sphere>
          </geometry>
        </visual>
      </link>
      <link name="sphere_2">
        <pose>0 -0.015000000000000003 0 0 0 0</pose>
        <collision name="collision">
          <geometry>
            <sphere>
              <radius>0.010000000000000002</radius>
            </sphere>
          </geometry>
          <surface>
            <friction>
              <ode>
                <mu>1000.0</mu>
                <mu2>1000.0</mu2>
              </ode>
              <torsional>
                <coefficient>0.005</coefficient>
                <patch_radius>2.0</patch_radius>
              </torsional>
            </friction>
          </surface>
        </collision>
        <visual name="visual">
          <geometry>
            <sphere>
              <radius>0.010000000000000002</radius>
            </sphere>
          </geometry>
        </visual>
      </link>
      <joint name = "joint_1" type="prismatic">
        <parent>world</parent>
        <child>sphere_1</child>
        <axis>
          <xyz>0 -1 0</xyz>
          <dynamics>
            <damping>100</damping>
            <spring_stiffness>1000000</spring_stiffness>
            <spring_reference>0.002</spring_reference>
          </dynamics>
        </axis>
      </joint>
      <joint name = "joint_2" type="prismatic">
        <parent>world</parent>
        <child>sphere_2</child>
        <axis>
          <xyz>0 1 0</xyz>
          <dynamics>
            <damping>100</damping>
            <spring_stiffness>1000000</spring_stiffness>
            <spring_reference>0.002</spring_reference>
          </dynamics>
        </axis>
      </joint>
    </model>

    <model name='pinch_4'>
      <allow_auto_disable>0</allow_auto_disable>
      <pose>4.817302149543871 6 0.6021627686929839 0 0 0</pose>
      <link name="box">
        <self_collide>true</self_collide>
        <pose>-0.24000000000000005 0 0 0 1.5707963267948966 0</pose>
        <inertial>
          <pose>0 0 0 0 0 0</pose>
          <mass>16.0</mass>
          <inertia>
            <ixx>0.4801333333333334</ixx>
            <iyy>0.48333333333333345</iyy>
            <izz>0.0034666666666666674</izz>
            <ixy>0.0</ixy>
            <ixz>0.0</ixz>
            <iyz>0.0</iyz>
          </inertia>
        </inertial>
        <collision name="collision">
          <geometry>
            <box>
              <size>0.05 0.010000000000000002 0.6000000000000001</size>
            </box>
          </geometry>
          <surface>
            <friction>
              <ode>
                <mu>1000.0</mu>
                <mu2>1000.0</mu2>
              </ode>
              <torsional>
                <coefficient>0.006</coefficient>
                <patch_radius>2.0</patch_radius>
              </torsional>
            </friction>
          </surface>
        </collision>
        <visual name="visual">
          <geometry>
            <box>
              <size>0.05 0.010000000000000002 0.6000000000000001</size>
            </box>
          </geometry>
        </visual>
      </link>
      <link name="sphere_1">
        <pose>0 0.015000000000000003 0 0 0 0</pose>
        <collision name="collision">
          <geometry>
            <sphere>
              <radius>0.010000000000000002</radius>
            </sphere>
          </geometry>
          <surface>
            <friction>
              <ode>
                <mu>1000.0</mu>
                <mu2>1000.0</mu2>
              </ode>
              <torsional>
                <coefficient>0.006</coefficient>
                <patch_radius>2.0</patch_radius>
              </torsional>
            </friction>
          </surface>
        </collision>
        <visual name="visual">
          <geometry>
            <sphere>
              <radius>0.010000000000000002</radius>
            </sphere>
          </geometry>
        </visual>
      </link>
      <link name="sphere_2">
        <pose>0 -0.015000000000000003 0 0 0 0</pose>
        <collision name="collision">
          <geometry>
            <sphere>
              <radius>0.010000000000000002</radius>
            </sphere>
          </geometry>
          <surface>
            <friction>
              <ode>
                <mu>1000.0</mu>
                <mu2>1000.0</mu2>
              </ode>
              <torsional>
                <coefficient>0.006</coefficient>
                <patch_radius>2.0</patch_radius>
              </torsional>
            </friction>
          </surface>
        </collision>
        <visual name="visual">
          <geometry>
            <sphere>
              <radius>0.010000000000000002</radius>
            </sphere>
          </geometry>
        </visual>
      </link>
      <joint name = "joint_1" type="prismatic">
        <parent>world</parent>
        <child>sphere_1</child>
        <axis>
          <xyz>0 -1 0</xyz>
          <dynamics>
            <damping>100</damping>
            <spring_stiffness>1000000</spring_stiffness>
            <spring_reference>0.002</spring_reference>
          </dynamics>
        </axis>
      </joint>
      <joint name = "joint_2" type="prismatic">
        <parent>world</parent>
        <child>sphere_2</child>
        <axis>
          <xyz>0 1 0</xyz>
          <dynamics>
            <damping>100</damping>
            <spring_stiffness>1000000</spring_stiffness>
            <spring_reference>0.002</spring_reference>
          </dynamics>
        </axis>
      </joint>
    </model>

    <model name='pinch_5'>
      <allow_auto_disable>0</allow_auto_disable>
      <pose>6.021627686929839 6 0.6021627686929839 0 0 0</pose>
      <link name="box">
        <self_collide>true</self_collide>
        <pose>-0.24000000000000005 0 0 0 1.5707963267948966 0</pose>
        <inertial>
          <pose>0 0 0 0 0 0</pose>
          <mass>16.0</mass>
          <inertia>
            <ixx>0.4801333333333334</ixx>
            <iyy>0.48333333333333345</iyy>
            <izz>0.0034666666666666674</izz>
            <ixy>0.0</ixy>
            <ixz>0.0</ixz>
            <iyz>0.0</iyz>
          </inertia>
        </inertial>
        <collision name="collision">
          <geometry>
            <box>
              <size>0.05 0.010000000000000002 0.6000000000000001</size>
            </box>
          </geometry>
          <surface>
            <friction>
              <ode>
                <mu>1000.0</mu>
                <mu2>1000.0</mu2>
              </ode>
              <torsional>
                <coefficient>1.0</coefficient>
                <patch_radius>2.0</patch_radius>
              </torsional>
            </friction>
          </surface>
        </collision>
        <visual name="visual">
          <geometry>
            <box>
              <size>0.05 0.010000000000000002 0.6000000000000001</size>
            </box>
          </geometry>
        </visual>
      </link>
      <link name="sphere_1">
        <pose>0 0.015000000000000003 0 0 0 0</pose>
        <collision name="collision">
          <geometry>
            <sphere>
              <radius>0.010000000000000002</radius>
            </sphere>
          </geometry>
          <surface>
            <friction>
              <ode>
                <mu>1000.0</mu>
                <mu2>1000.0</mu2>
              </ode>
              <torsional>
                <coefficient>1.0</coefficient>
                <patch_radius>2.0</patch_radius>
              </torsional>
            </friction>
          </surface>
        </collision>
        <visual name="visual">
          <geometry>
            <sphere>
              <radius>0.010000000000000002</radius>
            </sphere>
          </geometry>
        </visual>
      </link>
      <link name="sphere_2">
        <pose>0 -0.015000000000000003 0 0 0 0</pose>
        <collision name="collision">
          <geometry>
            <sphere>
              <radius>0.010000000000000002</radius>
            </sphere>
          </geometry>
          <surface>
            <friction>
              <ode>
                <mu>1000.0</mu>
                <mu2>1000.0</mu2>
              </ode>
              <torsional>
                <coefficient>1.0</coefficient>
                <patch_radius>2.0</patch_radius>
              </torsional>
            </friction>
          </surface>
        </collision>
        <visual name="visual">
          <geometry>
            <sphere>
              <radius>0.010000000000000002</radius>
            </sphere>
          </geometry>
        </visual>
      </link>
      <joint name = "joint_1" type="prismatic">
        <parent>world</parent>
        <child>sphere_1</child>
        <axis>
          <xyz>0 -1 0</xyz>
          <dynamics>
            <damping>100</damping>
            <spring_stiffness>1000000</spring_stiffness>
            <spring_reference>0.002</spring_reference>
          </dynamics>
        </axis>
      </joint>
      <joint name = "joint_2" type="prismatic">
        <parent>world</parent>
        <child>sphere_2</child>
        <axis>
          <xyz>0 1 0</xyz>
          <dynamics>
            <damping>100</damping>
            <spring_stiffness>1000000</spring_stiffness>
            <spring_reference>0.002</spring_reference>
          </dynamics>
        </axis>
      </joint>
    </model>

  </world>
</sdf>
