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Problem with "RobotModel" in Rviz #38

Closed ghx-0228 closed 5 years ago

ghx-0228 commented 5 years ago

I just execute the examples in your tutorial without any change. But all examples, except the 1st one, have such a problem "no transform from [] to []" as shown in the following figure. image

However, when I add "RobotState", it is alright, like this. image So could you help me solve the above problem?

DLu commented 5 years ago

The provided rviz configuration uses /base_link as the root frame, rather than /map which is the default. If you change the global fixed frame to base_link it will resemble the RobotState.

ghx-0228 commented 5 years ago

The global fixed frame was just /base_link. The "StateModel" had many "transform" errors image

DLu commented 5 years ago

Seems like you might be out of sync with the different steps of the tutorial, as if robot_state_publisher was seeing the previous version of the URDF. It doesn't automatically reload when the parameter changes.

vec123 commented 4 years ago

Hmmm i am having a very similar issue, where i get an transform error on a seemingly correct urdf (meaning e.g. i have a first link, then a follow_up joint which specifies the child link of that fist link and the chain continues like this). Now I expected that, when the first link is published to rviz, that then the chain would be processed, and therefore all links displayed. However this is the output:

image

The loaded launchfile loads the robot model like this:

<arg name="bin" default="$(find peg_in_hole)/urdf/r2d2.urdf"/>

<param name="r2d2/robot_description" command="$(find xacro)/xacro $(arg bin)" />

<node pkg="joint_state_publisher" type="joint_state_publisher" name="joint_state_publisher"/> <node pkg="robot_state_publisher" type="robot_state_publisher" name="robot_state_publisher"/>

<node name="rviz" pkg="rviz" type="rviz" required="true" />

I would expect these lines of code to load the .urdf description (which is correctly written, copied out of the tutorial) and publish the joints to /joint_states from where it goes to /tf and results in the display of the links.

I am pretty new to this so maybe i got something wrong. I can only tell that the joints never arrive at /tf or /tf_static, so i am guessing that something is missing, but i don't know what and can't seem to find anything.

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