Urdf Xacro Creation

URDF/Xacro 创建技能

机器人 URDF/Xacro 模型创建

何时使用

当需要以下帮助时使用此技能：

• URDF 语法
• Xacro 宏
• 传输配置 (transmission)
• 控制器配置
• ROS2 机器人状态发布

核心实现

URDF 模型

<!-- robot.urdf -->
<?xml version="1.0"?>
<robot name="robot_name">
  
  <!-- 链接定义 -->
  <link name="base_link">
    <visual>
      <origin xyz="0 0 0" rpy="0 0 0"/>
      <geometry>
        <box size="0.5 0.5 0.2"/>
      </geometry>
      <material name="blue">
        <color rgba="0 0 0.8 1"/>
      </material>
    </visual>
    
    <collision>
      <origin xyz="0 0 0" rpy="0 0 0"/>
      <geometry>
        <box size="0.5 0.5 0.2"/>
      </geometry>
    </collision>
    
    <inertial>
      <mass value="10.0"/>
      <origin xyz="0 0 0" rpy="0 0 0"/>
      <inertia ixx="0.1" ixy="0" ixz="0" iyy="0.1" iyz="0" izz="0.1"/>
    </inertial>
  </link>
  
  <!-- 关节定义 -->
  <joint name="joint1" type="revolute">
    <parent link="base_link"/>
    <child link="link1"/>
    <origin xyz="0.25 0 0" rpy="0 0 0"/>
    <axis xyz="0 0 1"/>
    <limit lower="-3.14" upper="3.14" effort="100" velocity="10"/>
    <dynamics damping="0.7" friction="0.5"/>
  </joint>
  
  <!-- 传输 -->
  <transmission name="joint1_trans">
    <type>transmission_interface/SimpleTransmission</type>
    <joint name="joint1">
      <hardwareInterface>hardware_interface/EffortJointInterface</hardwareInterface>
    </joint>
    <actuator name="motor1">
      <hardwareInterface>hardware_interface/EffortJointInterface</hardwareInterface>
      <mechanicalReduction>1</mechanicalReduction>
    </actuator>
  </transmission>
  
</robot>

Xacro 宏

<!-- robot.xacro -->
<?xml version="1.0"?>
<robot xmlns:xacro="http://www.ros.org/wiki/xacro">
  
  <!-- 常量定义 -->
  <xacro:property name="PI" value="3.14159"/>
  <xacro:property name="robot_name" value="my_robot"/>
  
  <!-- 宏定义 -->
  <xacro:macro name="box_inertia" params="mass width height depth *origin">
    <inertial>
      <xacro:insert_block name="origin"/>
      <mass value="${mass}"/>
      <inertia ixx="${mass/12*(height**2 + depth**2)}" 
               iyy="${mass/12*(width**2 + depth**2)}" 
               izz="${mass/12*(width**2 + height**2)}"/>
    </inertial>
  </xacro:macro>
  
  <!-- 包含其他文件 -->
  <xacro:include filename="$(find my_robot_description)/urdf/materials.xacro"/>
  
  <!-- 条件参数 -->
  <xacro:if value="$(arg use_gazebo)">
    <gazebo>
      <plugin name="gazebo_ros_control" filename="libgazebo_ros_control.so"/>
    </gazebo>
  </xacro:if>
  
</robot>

ROS2 控制器配置

# config/robot_controllers.yaml
controller_manager:
  ros__parameters:
    update_rate: 100
    
    joint_trajectory_controller:
      type: joint_trajectory_controller/JointTrajectoryController
    
    joint_state_broadcaster:
      type: joint_state_broadcaster/JointStateBroadcaster

joint_trajectory_controller:
  ros__parameters:
    joints:
      - joint1
      - joint2
    command_interfaces:
      - position
    state_interfaces:
      - position
      - velocity