URDF 文件中的多个 Realsense 摄像头

Question

我与 ROS 合作只有几个星期，如果我误解了一些事情，请见谅。我制作了一个带有机器人的 URDF 文件。现在我想在上面添加两个 Real-sense D435 相机，这样我就可以在 Rviz 中看到它。根据英特尔提供的测试文件，我在模型中显示了一个摄像头，但是，当我尝试创建第二个摄像头时，它却没有出现。

问题：如何在我的机器人上安装两个实感摄像头？

这是我的 URDF 文件：

<?xml version="1.0" ?>

<robot name="mrm" xmlns:xacro="http://www.ros.org/wiki/xacro">
  
  <!-- BGN - Include -->
  <xacro:include filename="$(find mrm_description)/urdf/robot_parameters.xacro" />
  <xacro:include filename="$(find mrm_description)/urdf/links_joints.xacro" />
  <xacro:include filename="$(find realsense2_camera)/urdf/_r435.urdf.xacro"/>
<xacro:include filename="$(find realsense2_camera)/urdf/_r430.urdf.xacro"/>


<m_link_box name="${link_00_name}"
              origin_rpy="0 0 0" origin_xyz="0 0 0"
              mass="1024"
              ixx="170.667" ixy="0" ixz="0"
              iyy="170.667" iyz="0"
              izz="170.667"
              size="1 1 1" />
              
  <m_joint name="${link_00_name}__${link_01_name}" type="revolute"
           axis_xyz="0 0 1"
           origin_rpy="0 0 0" origin_xyz="0 0 0.5"
           parent="base_link" child="link_01"
           limit_e="1000" limit_l="-3.14" limit_u="3.14" limit_v="0.5" />
           
  <m_link_mesh name="${link_01_name}"
              origin_rpy="0 0 0" origin_xyz="0 0 -0.1"
              mass="157.633"
              ixx="13.235" ixy="0" ixz="0"
              iyy="13.235" iyz="0"
              izz="9.655"
              meshfile="package://mrm_description/meshes/Link1-v2.stl"
              meshscale="0.001 0.001 0.001" />
  
  
              
  <m_joint name="${link_01_name}__${link_02_name}" type="revolute"
           axis_xyz="0 1 0"
           origin_rpy="0 0 0" origin_xyz="0 0 0.4"
           parent="link_01" child="link_02"
           limit_e="1000" limit_l="0" limit_u="0.5" limit_v="0.5" />
           
  <m_link_cylinder name="${link_02_name}"
              origin_rpy="0 0 0" origin_xyz="0 0 0.4"
              mass="57.906"
              ixx="12.679" ixy="0" ixz="0"
              iyy="12.679" iyz="0"
              izz="0.651"
              radius="0.15" length="0.8" />
              
  <m_joint name="${link_02_name}__${link_03_name}" type="revolute"
           axis_xyz="0 1 0"
           origin_rpy="0 0 0" origin_xyz="0 0 0.8"
           parent="link_02" child="link_03"
           limit_e="1000" limit_l="0" limit_u="0.75" limit_v="0.5" />
           
  <m_link_cylinder name="${link_03_name}"
              origin_rpy="0 0 0" origin_xyz="0 0 0.4"
              mass="57.906"
              ixx="12.679" ixy="0" ixz="0"
              iyy="12.679" iyz="0"
              izz="0.651"
              radius="0.15" length="0.8" />
              
  <m_joint name="${link_03_name}__${link_04_name}" type="revolute"
           axis_xyz="0 1 0"
           origin_rpy="0 0 0" origin_xyz="0 0 0.8"
           parent="link_03" child="link_04"
           limit_e="1000" limit_l="0" limit_u="0.75" limit_v="0.5" />
           
  <m_link_cylinder name="${link_04_name}"
              origin_rpy="0 0 0" origin_xyz="0 0 0.4"
              mass="57.906"
              ixx="12.679" ixy="0" ixz="0"
              iyy="12.679" iyz="0"
              izz="0.651"
              radius="0.15" length="0.8" />
              
  <m_joint name="${link_04_name}__${link_05_name}" type="revolute"
           axis_xyz="0 0 1"
           origin_rpy="0 0 0" origin_xyz="0 0 0.8"
           parent="link_04" child="link_05"
           limit_e="1000" limit_l="-3.14" limit_u="3.14" limit_v="0.5" />
           
  <m_link_cylinder name="${link_05_name}"
              origin_rpy="0 0 0" origin_xyz="0 0 0.125"
              mass="18.056"
              ixx="0.479" ixy="0" ixz="0"
              iyy="0.479" iyz="0"
              izz="0.204"
              radius="0.15" length="0.25" />

  <sensor_r435 name="Camera 1" parent="${link_05_name}">
        <origin xyz="0 0 0" rpy="1 0 0"/>
  </sensor_r435>  

  
<sensor_r435 name="Camera 2" parent="${link_05_name}">
    <origin xyz="0.17 0 0" rpy="0 0 0"/>
  </sensor_r435>
  
  <gazebo>
    <plugin name="gazebo_ros_control" filename="libgazebo_ros_control.so">
    </plugin>
  </gazebo>
  
</robot> 

Answer 1

看起来 realsense xacro 没有您提供的“名称”参数，所以它似乎没有做任何事情。理想情况下，您可以修改 intel xacro 行 -
<xacro:macro name="sensor_d415" params="parent *origin">
到
<xacro:macro name="sensor_d415" params="sensor_name parent *origin">
然后将${sensor_name}添加到intel xacro 中的每个链接和框架名称。因此，当您在 URDF 中使用不同的 sensor_name 包含此 xacro 时，您每次都会重新创建完整的描述。

如果您顺利完成这项工作，请向英特尔 github 页面提交拉取请求。

Answer 2

与此同时，在等待响应的同时，我创建了第二个文件，并在每个变量的末尾添加了 2，这很有效。当然，我知道这不是一个永久的解决方案，我应该将它保存在一个文件中。感谢 Vik，我有一个解决方案。我从第二个文件中取出所有变量并用 ${sensor_name} 替换它们。由于某种原因，相机不再出现在 rviz 中。我没有收到任何错误消息，但它们就消失了。人们可以看到我的代码是否存在任何问题？

   <?xml version="1.0"?>

<!--
License: Apache 2.0. See LICENSE file in root directory.
Copyright(c) 2017 Intel Corporation. All Rights Reserved

This is the URDF model for the Intel RealSense 430 camera, in it's
aluminum peripherial evaluation case.
-->

<robot name="sensor_d4352" xmlns:xacro="http://ros.org/wiki/xacro">
  <xacro:macro name="sensor_d415" params="sensor_name parent *origin">
    <xacro:property name="M_PI" value="3.1415926535897931" />

    <!-- The following values are approximate, and the camera node
     publishing TF values with actual calibrated camera extrinsic values -->
    <xacro:property name="d435_cam_depth_to_left_ir_offset" value="0.0"/>
    <xacro:property name="d435_cam_depth_to_right_ir_offset" value="-0.050"/>
    <xacro:property name="d435_cam_depth_to_color_offset" value="0.015"/>

    <!-- The following values model the aluminum peripherial case for the
    D435 camera, with the camera joint represented by the actual 
    peripherial camera tripod mount -->
    <xacro:property name="d435_cam_width" value="0.090"/>
    <xacro:property name="d435_cam_height" value="0.025"/>
    <xacro:property name="d435_cam_depth" value="0.02505"/>
    <xacro:property name="d435_cam_mount_from_center_offset" value="0.0149"/>

    <!-- The following offset is relative the the physical D435 camera peripherial
    camera tripod mount -->
    <xacro:property name="d435_cam_depth_px" value="${d435_cam_mount_from_center_offset}"/>
    <xacro:property name="d435_cam_depth_py" value="0.0175"/>
    <xacro:property name="d435_cam_depth_pz" value="${d435_cam_height/2}"/>

    <material name="aluminum${sensor_name}">
      <color rgba="0.5 0.5 0.5 1"/>
    </material>


    <!-- camera body, with origin at bottom screw mount -->
    <joint name="camera_joint${sensor_name}" type="fixed">
      <xacro:insert_block name="origin" />
      <parent link="${parent}"/>
      <child link="camera_bottom_screw_frame${sensor_name}" />
    </joint>
    <link name="camera_bottom_screw_frame${sensor_name}"/>

    <joint name="camera_link_joint${sensor_name}" type="fixed">
      <origin xyz="0 ${d435_cam_depth_py} ${d435_cam_depth_pz}" rpy="0 0 0"/>
      <parent link="camera_bottom_screw_frame${sensor_name}"/>
      <child link="camera_link${sensor_name}" />
    </joint>

    <link name="camera_link${sensor_name}">
      <visual>
      <origin xyz="${d435_cam_mount_from_center_offset} ${-d435_cam_depth_py} 0" rpy="${M_PI/2} 0 ${M_PI/2}"/>
        <geometry>
          <!-- <box size="${d435_cam_width} ${d435_cam_height} ${d435_cam_depth}"/> -->
      <mesh filename="package://realsense2_camera/meshes/d435.dae" />
          <!--<mesh filename="package://realsense2_camera/meshes/d435/d435.dae" />-->

        </geometry>
        <material name="aluminum"/>
      </visual>
      <collision>
        <origin xyz="0 ${-d435_cam_depth_py} 0" rpy="0 0 0"/>
        <geometry>
        <box size="${d435_cam_depth} ${d435_cam_width} ${d435_cam_height}"/>
        </geometry>
      </collision>
      <inertial>
        <!-- The following are not reliable values, and should not be used for modeling -->
        <mass value="0.564" />
        <origin xyz="0 0 0" />
        <inertia ixx="0.003881243" ixy="0.0" ixz="0.0" iyy="0.000498940" iyz="0.0" izz="0.003879257" />
      </inertial>
    </link>


<!-- camera depth joints and links -->
<joint name="camera_depth_joint${sensor_name}" type="fixed">
  <origin xyz="0 0 0" rpy="0 0 0"/>
  <parent link="camera_link${sensor_name}"/>
  <child link="camera_depth_frame${sensor_name}" />
</joint>
<link name="camera_depth_frame${sensor_name}"/>

<joint name="camera_depth_optical_joint${sensor_name}" type="fixed">
  <origin xyz="0 0 0" rpy="${-M_PI/2} 0 ${-M_PI/2}" />
  <parent link="camera_depth_frame${sensor_name}" />
  <child link="camera_depth_optical_frame${sensor_name}" />
</joint>
<link name="camera_depth_optical_frame${sensor_name}"/>

<!-- camera left IR joints and links -->
<joint name="camera_left_ir_joint${sensor_name}" type="fixed">
  <origin xyz="0 ${d435_cam_depth_to_left_ir_offset} 0" rpy="0 0 0" />
  <parent link="camera_depth_frame${sensor_name}" />
  <child link="camera_left_ir_frame${sensor_name}" />
</joint>
<link name="camera_left_ir_frame${sensor_name}"/>

<joint name="camera_left_ir_optical_joint${sensor_name}" type="fixed">
  <origin xyz="0 0 0" rpy="${-M_PI/2} 0 ${-M_PI/2}" />
  <parent link="camera_left_ir_frame${sensor_name}" />
  <child link="camera_left_ir_optical_frame${sensor_name}" />
</joint>
<link name="camera_left_ir_optical_frame${sensor_name}"/>

<!-- camera right IR joints and links -->
<joint name="camera_right_ir_joint${sensor_name}" type="fixed">
  <origin xyz="0 ${d435_cam_depth_to_right_ir_offset} 0" rpy="0 0 0" />
  <parent link="camera_depth_frame${sensor_name}" />
  <child link="camera_right_ir_frame${sensor_name}" />
</joint>
<link name="camera_right_ir_frame${sensor_name}"/>

<joint name="camera_right_ir_optical_joint${sensor_name}" type="fixed">
  <origin xyz="0 0 0" rpy="${-M_PI/2} 0 ${-M_PI/2}" />
  <parent link="camera_right_ir_frame${sensor_name}" />
  <child link="camera_right_ir_optical_frame${sensor_name}" />
</joint>
<link name="camera_right_ir_optical_frame${sensor_name}"/>

<!-- camera color joints and links -->
<joint name="camera_color_joint${sensor_name}" type="fixed">
  <origin xyz="0 ${d435_cam_depth_to_color_offset} 0" rpy="0 0 0" />
  <parent link="camera_depth_frame" />
  <child link="camera_color_frame${sensor_name}" />
</joint>
<link name="camera_color_frame${sensor_name}"/>

<joint name="camera_color_optical_joint${sensor_name}" type="fixed">
  <origin xyz="0 0 0" rpy="${-M_PI/2} 0 ${-M_PI/2}" />
  <parent link="camera_color_frame${sensor_name}" />
  <child link="camera_color_optical_frame${sensor_name}" />
</joint>
<link name="camera_color_optical_frame"/>
</xacro:macro>
</robot>