Visual odometry and zed's IMU fusion on RTAB-Map

**"When using /camera/odom, you don't need to use visual_odometry node. rtabmap should be subscribed to /odometry/flltered if you want to use odometry output from IMU and /camera/odometry fusion, otherwise IMU is ignored if rtabmap is subscribed directly to /camera/odom. **

To get a good fusion between IMU and vo, the transform between the sensors should be very precise. You can use kalibr tool to get this information and get more precise TF. "

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Open zed

zed test

cd /usr/local/zed/tools/

./ZED\ Explorer

If the camera can be openned, turn it off.

As the tutorial in ROS said,

I want to use IMU data in zed, so

$ export ROS_NAMESPACE=camera
$ roslaunch zed_wrapper zed_camera.launch publish_map_tf:=false

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Enter the mapping mode

As the tutorial in ROS said,

I want to use IMU data in zed, so

$ roslaunch rtabmap_ros rtabmap.launch rtabmap_args:="--delete_db_on_start" depth_topic:=/camera/depth/depth_registered frame_id:=zed_camera_center approx_sync:=false visual_odometry:=false odom_topic:=/camera/odom

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These days a more convenient way to launch rtabmap with zed

roslaunch zed_rtabmap_example zed_rtabmap.launch

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References:

[1] Fusion on zed and imu, but the map drifted immediately

[2] RGB-D Handheld Mapping