diff_drive_4.urdf.xacro

<?xml version="1.0"?>
<robot name="roscontrol" xmlns:xacro="http://ros.org/wiki/xacro">

  <!--
    Run the following command to check if the urdf file is ok:
    ~$ xacro diff_drive_4.urdf.xacro > tmp.urdf && check_urdf tmp.urdf && rm tmp.urdf
  -->

  <!-- Xacro properties definition -->
  <xacro:property name="odom_dist_wh" value="0.2"/>
  <xacro:property name="odom_diam_wh_r" value="0.06"/>
  <xacro:property name="odom_diam_wh_l" value="0.06"/>
  <xacro:property name="odom_diam"
                  value="${(odom_diam_wh_r+odom_diam_wh_l)/2}"/>
  <xacro:property name="wh_thick" value="0.005"/>
  <xacro:property name="body_gnd_height" value="0.02"/>
  <xacro:property name="body_wh_space" value="0.005"/>
  <xacro:property name="body_len" value="0.3"/>
  <xacro:property name="body_width"
                  value="${odom_dist_wh-wh_thick-2*body_wh_space}"/>
  <xacro:property name="body_height" value="0.1"/>


  <!-- Materials definition -->
  <material name="blue">
    <color rgba="0 0 0.8 1"/>
  </material>

  <material name="black">
    <color rgba="0 0 0 1"/>
  </material>

  <material name="white">
    <color rgba="1 1 1 1"/>
  </material>


  <!-- Xacro Macro definitions -->
  <!-- + inertial models: -->
  <xacro:include
    filename="$(find robot_sim_diff_drive_rbs)/urdf/inertia.urdf.xacro"/>

  <!-- + wheel macro:
         - prefix  : relative to the default name
         - sufix   : relative to the default name
         - reflect : 1 or -1 (default or inverted orientation relative to
                     parent frame)
         - offset  : relative to the parent frame in x axis -->
  <xacro:macro name="wheel" params="prefix suffix reflect offset:=0">
    <link name="${prefix}_${suffix}_wheel">
      <visual>
        <!-- Origin relative to the link frame -->
        <origin xyz="0 0 0" rpy="${pi/2} 0 0" />
        <geometry>
          <cylinder radius="${odom_diam/2}" length="${wh_thick}"/>
        </geometry>
        <material name="black"/>
      </visual>
      <collision>
        <origin xyz="0 0 0" rpy="${pi/2} 0 0" />
        <geometry>
          <cylinder radius="${odom_diam/2}" length="${wh_thick}"/>
        </geometry>
      </collision>
      <xacro:inertial_wh_cylinder mass="0.05"
                                  radius="${odom_diam/2}" height="${wh_thick}"/>
    </link>
    <joint name="${prefix}_${suffix}_wheel_joint" type="continuous">
      <!-- axis and rotation always defined relative to parent frame -->
      <axis xyz="0 1 0" rpy="0 0 0" />
      <parent link="base_link"/>
      <child link="${prefix}_${suffix}_wheel"/>
      <origin xyz="${offset} ${reflect*odom_dist_wh/2} 0" rpy="0 0 0"/>
    </joint>
    <!-- This block provides the simulator (Gazebo) with information on a few
         additional physical properties.
         See http://gazebosim.org/tutorials/?tut=ros_urdf for more-->
    <gazebo reference="${prefix}_${suffix}_wheel">
      <fdir1 value="1 0 0"/>
      <mu1 value="1.0"/>
      <mu2 value="1.0"/>
      <kp value="10000000.0"/>
      <kd value="1.0"/>
      <material>Gazebo/Grey</material>
    </gazebo>

    <!-- This block connects the wheel joint to an actuator (motor), which informs both
    simulation and visualization of the robot -->
    <transmission name="${prefix}_${suffix}_wheel_trans">
      <type>transmission_interface/SimpleTransmission</type>
      <actuator name="${prefix}_${suffix}_wheel_motor">
        <mechanicalReduction>1</mechanicalReduction>
      </actuator>
      <joint name="${prefix}_${suffix}_wheel_joint">
        <hardwareInterface>VelocityJointInterface</hardwareInterface>
      </joint>
    </transmission>
  </xacro:macro>


  <!-- Body -->
  <link name="base_link">
    <visual>
      <origin xyz="0 0 ${-odom_diam/2+body_gnd_height+body_height/2}"
              rpy="0 0 0"/>
      <geometry>
        <box size="${body_len} ${body_width} ${body_height}"/>
      </geometry>
      <material name="blue"/>
    </visual>
    <collision>
      <origin xyz="0 0 ${-odom_diam/2+body_gnd_height+body_height/2}"
              rpy="0 0 0"/>
      <geometry>
        <box size="${body_len} ${body_width} ${body_height}"/>
      </geometry>
    </collision>
    <xacro:inertial_body_cuboid mass="1.00"
                                size_x="${body_len}" size_y="${body_width}"
                                size_z="${body_height}"/>
  </link>


  <!-- Wheels -->
  <xacro:wheel prefix="right" suffix="front" reflect="-1"
               offset="${body_len/2-odom_diam/2}"/>
  <xacro:wheel prefix="left"  suffix="front" reflect="1"
               offset="${body_len/2-odom_diam/2}"/>
  <xacro:wheel prefix="right" suffix="back"  reflect="-1"
               offset="-${body_len/2-odom_diam/2}"/>
  <xacro:wheel prefix="left"  suffix="back"  reflect="1"
               offset="-${body_len/2-odom_diam/2}"/>


  <!-- Sensors -->
  <xacro:include
      filename="$(find robot_sim_diff_drive_rbs)/urdf/hokuyo_ust10.urdf.xacro"/>
  <xacro:hokuyo_ust10_mount prefix="base" topic="base_laser"
                            parent_link="base_link">
    <origin xyz="0 0 ${-odom_diam/2+body_gnd_height+body_height}"
            rpy="0 0 0"/>
  </xacro:hokuyo_ust10_mount>


  <!-- Gazebo plugin for ROS Control -->
  <gazebo>
    <plugin name="gazebo_ros_control" filename="libgazebo_ros_control.so">
      <robotNamespace>/</robotNamespace>
    </plugin>
  </gazebo>

</robot>