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Canot change parent child relationship between base_link and base_footprint

I have changed a part of the code from

<joint name="base_footprint_joint" type="fixed">
    <parent link="base_link"/>
    <child link="base_footprint"/>
    <origin xyz="0 0 0" rpy="0 0 0"/>
</joint>
<link name="base_footprint">
</link>

to

 <joint name="base_footprint_joint" type="fixed">
    <parent link="base_footprint"/>
    <child link="base_link"/>
    <origin xyz="0 0 0" rpy="0 0 0"/>
</joint>
<link name="base_footprint">
</link>

this before changing to this after changing

but the basefootprint disappears instead of becoming parent to baselink what to do , please help. Thank you.

Asked by iamsdevaprasad on 2023-07-19 11:16:14 UTC

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Answers

This might be a stupid answer, but have you tried this?

<link name="base_footprint">
</link>
<joint name="base_footprint_joint" type="fixed">
    <parent link="base_footprint"/>
    <child link="base_link"/>
    <origin xyz="0 0 0" rpy="0 0 0"/>
</joint>

Although my spider sense tells me that you should modify your setup so that gazebo publishes the transform "odom -> base_footprint" instead of "odom -> base_link"

Asked by Martin Peris on 2023-07-19 20:52:41 UTC

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Thanks for the answer, but it didn't work. Any other tips ...

Asked by iamsdevaprasad on 2023-07-19 21:08:28 UTC

Although my spider sense tells me that you should modify your setup so that gazebo publishes the transform "odom -> base_footprint" instead of "odom -> base_link"

I know about it , but not sure how to do it...

Asked by iamsdevaprasad on 2023-07-19 21:21:35 UTC

I have found the answer to change the child link for odom frame it should be done in robot.gazebo file where you have added the differential drive plugin , not in robot.xacro file.

To be more precise what you have to do is 

<joint name="base_footprint_joint" type="fixed">
    <parent link="base_footprint"/>
    <child link="base_link"/>
    <origin xyz="0 0 0" rpy="0 0 0"/>
</joint>

<link name="base_footprint">
</link>

change this part of code in robot.xacro.

Then go to robot.gazebo and in diff drive plugin change.

<robotBaseFrame>base_footprint</robotBaseFrame>

now the tf graph goes as odom-->base_footprint-->base_link ...

Asked by iamsdevaprasad on 2023-07-20 12:15:29 UTC

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