Using robot_localization with amcl [closed]

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Hi all,

I am starting to set up awesome robot_localization package and I am using rotary encoders (nav_msgs/Odometry, both pose and twist) and IMU (sensor_msgs/Imu) which provides continuous data and Ultrawide band sensor which provides global absolute position data as a nav_msgs/Odometry message (only pose, (x,y and yaw)) . As suggested on the wiki page of the package, I can fuse data from the encoders and the IMU in the odom_frame which gives the transform odom_frame -> base_link_frame. For the map_frame, I can fuse data from rotary_encoders, IMU and Ultrawide band sensor (It is similar to GPS in the sense that it provides global absolute position data) and it gives the transfrom from map_frame -> odom_frame but next I am using amcl to improve the pose_estimate and amcl also provides map_frame->odom_frame transformation. So, I want to ask how should I deal with the transformations (specifically map_frame->odom_frame), Should I just not use the map_frame->odom_frame transformation from robot_localization and let amcl take care of it, If yes how can I not use the transformation? Or is there any better way to deal with it?

Update 1:
If I give output of AMCL and UWB to second instance of ekf_localization_node, it will give me the required transformation (map_frame -> odom_frame) and will publish the output odometry message on odometry/filtered topic but I am using move_base which expects robot pose on /amcl_pose topic. So, I can remap the output on odometry/filtered to amcl_pose and change the message type from nav_msgs/Odometry to geometry_msgs/PoseWithCovarianceStamped, Does that sound okay?

Also, another approach which I am thinking is to run the first instance of ekf_localization_node (in odom_frame) with rotary encoders and IMU as input which will give odom_frame->base_link_frame transformation and then run second instance of ekf_localization_node (in map_frame) with UWB, rotary encoders and IMU as input. I am slightly confused about how the second instance will work. Will it modify the odom_frame -> base_link_frame tf by considering (or changing) the data from UWB in the odom_frame? If yes, then I can directly use the modified odom_frame->base_link_frame tf (which includes UWB, encoders and IMU) (and ignore map_frame->odom_frame tf from second instance of ekf_localization_node) in amcl and everything should be fine, right?

Update 2:
Thanks @Tom Moore for the answer! So just to clarify, run the first instance of ekf_localization_node in odom_frame with wheel odometry and IMU data as input which will give us the odom_frame -> base_link_frame transformation. Then run the second instance of the ekf_localization_node in the map_frame with wheel odometry, IMU data, UWB data (it is in map_frame) and amcl_pose which will give us the map_frame -> odom_frame transformation using existing odom_frame -> base_link_frame tf.

Thanks in advance.
Naman Kumar