update padFootprint() function

[Nisarg236]

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Basic Info

Info	Please fill out this column
Ticket(s) this addresses	(add tickets here #1)
Primary OS tested on	(Ubuntu, MacOS, Windows)
Robotic platform tested on	(Steve's Robot, gazebo simulation of Tally, hardware turtlebot)
Does this PR contain AI generated software?	(No; Yes and it is marked inline in the code)

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Description of contribution in a few bullet points

• Footprint gets distorted when the origin of the footprint is not at the centroid of the footprint.
• Negative values of padding will shrink the footprint

Case 1: (0,0), (0,2), (2,2), (2,0)

Case 2: (10,10), (10,12), (12,12) , (12,10)

Description of documentation updates required from your changes

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Future work that may be required in bullet points

For Maintainers:

• Check that any new parameters added are updated in docs.nav2.org
• Check that any significant change is added to the migration guide
• Check that any new features OR changes to existing behaviors are reflected in the tuning guide
• Check that any new functions have Doxygen added
• Check that any new features have test coverage
• Check that any new plugins is added to the plugins page
• If BT Node, Additionally: add to BT's XML index of nodes for groot, BT package's readme table, and BT library lists

[mergify]

@Nisarg236, your PR has failed to build. Please check CI outputs and resolve issues.
You may need to rebase or pull in main due to API changes (or your contribution genuinely fails).

[mergify]

@Nisarg236, your PR has failed to build. Please check CI outputs and resolve issues.
You may need to rebase or pull in main due to API changes (or your contribution genuinely fails).

[SteveMacenski]

Please fix build, linting, and DCO issues before we give this a review :-)

[SteveMacenski]

Please point out to me the error in the code here - I don't see any immediately.

Is the issue the case where you have a coordinate exactly at 0.0? 0.0 for the footprint would be the center of your robot, since that is the 0.0, 0.0 w.r.t. your base_link or base_footprint frame -- which is almost always the center of your robot or aligned with some axle that wouldn't then be a corner of a robot. That would point to me more an issue in your configuration

[SteveMacenski]

See https://docs.nav2.org/setup_guides/footprint/setup_footprint.html

[SteveMacenski]

@Nisarg236 should this be closed?