使用RealsenseD435i运行VINS-Fusion
VINS-Fusion是基于双目的视觉惯导方案，不太符合我目前的需求，但这是我使用的第一个视觉SLAM方案，接下来还是简单记录下

运行环境
硬件环境：Up2、RealsenseD435i

软件环境：Ubuntu18.04、ROS melodic、librealsense2.29、realsense-ros2.2.9

安装
首先需要安装Ceres-solver依赖项，安装过程见http://ceres-solver.org/installation.html

接着下载并使用catkin_make编译VINS-Fusion

cd ~/catkin_ws/src
git clone https://github.com/HKUST-Aerial-Robotics/VINS-Fusion.git
cd ../
catkin_make
source ~/catkin_ws/devel/setup.bash

下载缓慢的话可以将https://github.com/HKUST-Aerial-Robotics/VINS-Fusion.git改成https://gitee.com/jylhaust/VINS-Fusion.git

运行
修改rs_camera.launch，重命名为rs_camera_vins.launch，将它保存在~/catkin_ws/src/realsense-ros/realsense2_camera/launch/目录下，简单修改一下内容，如下：

<launch>
  <arg name="serial_no"           default=""/>
  <arg name="usb_port_id"         default=""/>
  <arg name="device_type"         default=""/>
  <arg name="json_file_path"      default=""/>
  <arg name="camera"              default="camera"/>
  <arg name="tf_prefix"           default="$(arg camera)"/>
  <arg name="external_manager"    default="false"/>
  <arg name="manager"             default="realsense2_camera_manager"/>

  <arg name="fisheye_width"       default="640"/>
  <arg name="fisheye_height"      default="480"/>
  <arg name="enable_fisheye"      default="false"/>

  <arg name="depth_width"         default="640"/>
  <arg name="depth_height"        default="480"/>
  <arg name="enable_depth"        default="true"/>

  <arg name="infra_width"        default="640"/>
  <arg name="infra_height"       default="480"/>
  <arg name="enable_infra1"       default="true"/>
  <arg name="enable_infra2"       default="true"/>

  <arg name="color_width"         default="640"/>
  <arg name="color_height"        default="480"/>
  <arg name="enable_color"        default="true"/>

  <arg name="fisheye_fps"         default="30"/>
  <arg name="depth_fps"           default="30"/>
  <arg name="infra_fps"           default="30"/>
  <arg name="color_fps"           default="30"/>
  <arg name="gyro_fps"            default="200"/>
  <arg name="accel_fps"           default="250"/>
  <arg name="enable_gyro"         default="true"/>
  <arg name="enable_accel"        default="true"/>

  <arg name="enable_pointcloud"         default="false"/>
  <arg name="pointcloud_texture_stream" default="RS2_STREAM_COLOR"/>
  <arg name="pointcloud_texture_index"  default="0"/>

  <arg name="enable_sync"               default="true"/>
  <arg name="align_depth"               default="true"/>

  <arg name="publish_tf"                default="true"/>
  <arg name="tf_publish_rate"           default="0"/>

  <arg name="filters"                   default=""/>
  <arg name="clip_distance"             default="-2"/>
  <arg name="linear_accel_cov"          default="0.01"/>
  <arg name="initial_reset"             default="false"/>
  <arg name="unite_imu_method"          default="linear_interpolation"/>
  <arg name="topic_odom_in"             default="odom_in"/>
  <arg name="calib_odom_file"           default=""/>
  <arg name="publish_odom_tf"           default="true"/>
  <arg name="allow_no_texture_points"   default="false"/>
  <arg name="emitter_enable"   		default="false"/>

<!-- rosparam set /camera/stereo_module/emitter_enabled false -->
<rosparam>
  /camera/stereo_module/emitter_enabled: 0
</rosparam>

<rosparam if="$(arg emitter_enable)">
  /camera/stereo_module/emitter_enabled: 1
</rosparam>

  <group ns="$(arg camera)">
    <include file="$(find realsense2_camera)/launch/includes/nodelet.launch.xml">
      <arg name="tf_prefix"                value="$(arg tf_prefix)"/>
      <arg name="external_manager"         value="$(arg external_manager)"/>
      <arg name="manager"                  value="$(arg manager)"/>
      <arg name="serial_no"                value="$(arg serial_no)"/>
      <arg name="usb_port_id"              value="$(arg usb_port_id)"/>
      <arg name="device_type"              value="$(arg device_type)"/>
      <arg name="json_file_path"           value="$(arg json_file_path)"/>

      <arg name="enable_pointcloud"        value="$(arg enable_pointcloud)"/>
      <arg name="pointcloud_texture_stream" value="$(arg pointcloud_texture_stream)"/>
      <arg name="pointcloud_texture_index"  value="$(arg pointcloud_texture_index)"/>
      <arg name="enable_sync"              value="$(arg enable_sync)"/>
      <arg name="align_depth"              value="$(arg align_depth)"/>

      <arg name="fisheye_width"            value="$(arg fisheye_width)"/>
      <arg name="fisheye_height"           value="$(arg fisheye_height)"/>
      <arg name="enable_fisheye"           value="$(arg enable_fisheye)"/>

      <arg name="depth_width"              value="$(arg depth_width)"/>
      <arg name="depth_height"             value="$(arg depth_height)"/>
      <arg name="enable_depth"             value="$(arg enable_depth)"/>

      <arg name="color_width"              value="$(arg color_width)"/>
      <arg name="color_height"             value="$(arg color_height)"/>
      <arg name="enable_color"             value="$(arg enable_color)"/>

      <arg name="infra_width"              value="$(arg infra_width)"/>
      <arg name="infra_height"             value="$(arg infra_height)"/>
      <arg name="enable_infra1"            value="$(arg enable_infra1)"/>
      <arg name="enable_infra2"            value="$(arg enable_infra2)"/>

      <arg name="fisheye_fps"              value="$(arg fisheye_fps)"/>
      <arg name="depth_fps"                value="$(arg depth_fps)"/>
      <arg name="infra_fps"                value="$(arg infra_fps)"/>
      <arg name="color_fps"                value="$(arg color_fps)"/>
      <arg name="gyro_fps"                 value="$(arg gyro_fps)"/>
      <arg name="accel_fps"                value="$(arg accel_fps)"/>
      <arg name="enable_gyro"              value="$(arg enable_gyro)"/>
      <arg name="enable_accel"             value="$(arg enable_accel)"/>

      <arg name="publish_tf"               value="$(arg publish_tf)"/>
      <arg name="tf_publish_rate"          value="$(arg tf_publish_rate)"/>

      <arg name="filters"                  value="$(arg filters)"/>
      <arg name="clip_distance"            value="$(arg clip_distance)"/>
      <arg name="linear_accel_cov"         value="$(arg linear_accel_cov)"/>
      <arg name="initial_reset"            value="$(arg initial_reset)"/>
      <arg name="unite_imu_method"         value="$(arg unite_imu_method)"/>
      <arg name="topic_odom_in"            value="$(arg topic_odom_in)"/>
      <arg name="calib_odom_file"          value="$(arg calib_odom_file)"/>
      <arg name="publish_odom_tf"          value="$(arg publish_odom_tf)"/>
      <arg name="allow_no_texture_points"  value="$(arg allow_no_texture_points)"/>
    </include>
  </group>
</launch>

下面这段用于关闭激光发射器，防止干扰两个红外摄像头。

<!-- rosparam set /camera/stereo_module/emitter_enabled false -->
<rosparam>
  /camera/stereo_module/emitter_enabled: 0
</rosparam>
<rosparam if="$(arg emitter_enable)">
  /camera/stereo_module/emitter_enabled: 1
</rosparam>

再编写一个launch文件，命名为my_vins_d435.launch，也保存在~/catkin_ws/src/realsense-ros/realsense2_camera/launch/目录下，内容如下：

<launch>
	<include file="$(find realsense2_camera)/launch/rs_camera_vins.launch"/>	
	<include file="$(find vins)/launch/vins_rviz.launch"/>
	<!--node pkg="vins" type="vins_node" name="vins_node">
		<param name="config_file" value="~/catkin_ws/src/VINS-Fusion/config/realsense_d435i/realsense_stereo_imu_config.yaml""/>
	</node-->	
</launch>

命令行输入roslaunch realsense2_camera my_vins_d435.launch即可。然后执行：

rosrun vins vins_node ~/catkin_ws/src/VINS-Fusion/config/realsense_d435i/realsense_stereo_imu_config.yaml

就可以运行VINS-Fusion了，其中realsense_stereo_imu_config.yaml是相机的配置文件，我们需要将里面的相机参数修改为自己的相机参数

运行效果

很容易漂，应该是我还没标定相机的原因，标定后效果应该好点，但纯CPU运行会有很大的滞后