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Hello, I keep getting confused with this every once in a while, and I can't find a definite resource for the convention. The frame id is supposed to be: #Frame this data is associated with

To represent the pose of an object in the map, I'm not sure what convention is used. i.e.. if the data should be in the frame of object (camera, robot,etc..) or in the frame of the map. In CV, SLAM literature, the 'pose' represented by a Rotation (R), and translation (t) is usually in the frame of the camera,
i.e. R contains the coordinates of the bases of the map frame in the Camera frame, and t is the translation in the Camera frame, or X_camera = R*X_map + t where X_map is a point in the map frame, and X_camera the same point in the camera frame.

From what I understand, it seems like the the frame_id should be Camera for orientation R (in quaternion) and position (t), and map for orientation inv(R) (in quat) and position -inv(R)*t, but I've lost count of the number of times I've gotten confused with this. Would appreciate it if you could point me to some documentation on this convention.

The documentation for the transform, and pose conventions I was looking for can be found here: http://wiki.ros.org/tf/Ov

The documentation for the transform, and pose conventions I was looking for can be found here: http://wiki.ros.org/tf/Ov

@Per Edwardsson thanks for the comment. . but saying that transform is a pose is going to be confusing in this conte

@Per Edwardsson thanks for the comment. . but saying that transform is a pose is going to be confusing in this conte

Hello @Mike Scheutzow can you please expand on why you think this interpretation is a misunderstanding?

How so? A pose can very much be seen as a transform. While computing the Projection matrix for a camera, the extrinsics

How so? A pose can very much be seen as a transform. While computing the Projection matrix for a camera, the extrinsics

How so? A pose can very much be seen as a transform. While computing the Projection matrix for a camera, the extrinsics

"The location of the object in that frame is well defined as a Pose (http://docs.ros.org/en/noetic/api/geo...), ie a 3D

"The location of the object in that frame is well defined as a Pose (http://docs.ros.org/en/noetic/api/geo...), ie a 3D

Hello, I'm not sure if my question was confusing, but this is not what I meant. The question was more about the conventi

Hello, I'm not sure if my question was confusing, but this is not what I meant. The question was more about the conventi

Ah sorry, I thought the previous post failed to upload

Question on ROS frame convention Hello, I keep getting confused with this every once in a while, and I can't find a defi

ROS convention for frame_id in PoseStamped data Hello, I keep getting confused with this every once in a while, and I ca

ROS convention for frame_id in PoseStamped data Hello, I keep getting confused with this every once in a while, and I ca

ROS convention for frame_id in PoseStamped data Hello, I keep getting confused with this every once in a while, and I ca

Thanks for the suggestion! I'll check it out

EKF for robot poses Hello, As per my understanding, the robot_pose_ekf package can be used to merge 2D pose + IMU + 3D

Yeah, I'm aware of that. Unfortunately, only the /camera/aligned_depth_to_color/image_raw/compressed topic was recorded,

ah, okay. My problem is with jpeg. I think it works fine for other compression formats which support 16 bit.

Making sense of 16-bit jpeg compressed data from Intel RealSense D435i camera Hello, I recorded some data from an Intel

Making sense of 16-bit jpeg compressed data from Intel RealSense D435i camera Hello, I recorded some data from an Intel

Hi, thank you! Let me try this out. Were you using this for the compressed topic?

Making sense of 16-bit jpeg compressed data from Intel RealSense D435i camera Hello, I recorded some data from an Intel

Making sense of 16-bit jpeg compressed data from Intel RealSense D435i camera Hello, I recorded some data from an Intel

Making sense of 16-bit jpeg compressed data from Intel RealSense D435i camera Hello, I recorded some data from an Intel

Issues with subscribing to multiple camera image topics ROS: Noetic Ubuntu: 20.04 Hello, I'm having a strange issue whe

Issues with subscribing to multiple camera image topics ROS: Noetic Ubuntu: 20.04 Hello, I'm having a strange issue whe

Thanks again, for your help. If I mention a frame ID in the jackal_description/urdf/jackal.gazebo file, it does change t

Thanks again, for your help. If I do mention a frame ID in the jackal_description/urdf/jackal.gazebo file, it does chang

Hello,

<group if="$(arg enable_ekf)" > 
  <node pkg="robot_localization" type="ekf_localization_node" name="ekf_localization"  >
    <rosparam command="load" file="$(arg ekf_yaml_path)" />
    <param name="map_frame"       value="map"/>
    <param name="odom_frame"      value="$(arg ns)/odom"/>
    <param name="base_link_frame" value="$(arg ns)/base_link"/>
    <param name="world_frame"     value="$(arg ns)/odom"/>
  </node>
</group>

The above are the relevant lines in my launch file, but when I try it to run it, there are warnings thrown and the functionality is not as expected. The warnings are as below:

[WARN] [1617652671.519795535, 1553.900000000]: Could not obtain transform from base_link to jackal2/base_link. Error was "base_link" passed to lookupTransform argument source_frame does not exist.
"base_link" passed to lookupTransform argument source_frame does not exist.

I don't understand why these would come up since I am specifically assigning a base_link_frame. Why does it matter if "base_link" exists or not?