Is there any examples to use approximate constraint manifold in moveit?

Question

Hi all, I intend to do planning with approximated constraint manifold to make sure that the end effector can only rotate along the z_axis of the base link. Following the tutorial, I generated and loaded the database, but not sure know how to use it in move_group c++ interface.

Another question: Can I load two constraint databases when launching move_group? or Can I include two constraints in one database?

Thanks for any help!

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Originally posted by xibeisiber on ROS Answers with karma: 137 on 2021-11-03

Post score: 0

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Original comments

Comment by gvdhoorn on 2021-11-08:\

Another question: Can I load two constraint databases when launching move_group? or Can I include two constraints in one database?

Do not post follow-up questions as edits to questions which have already been answered.

Your follow-up question has almost 0 visibility.

You should post a new question.

Comment by v4hn on 2021-11-08:
Gijs is right, I would not have seen this without his comment. I edited the answer below.

Answer 1

as answered by @v4hn here: https://github.com/ros-planning/moveit/issues/2941.

The move_group node loads the database on startup and registers the name of the constraint that you defined when you generated the database. To use it for planning you just have to set a path constraint with the same constraint name. Make sure you also add the full constraint specification there as well though because this message is still used to check transitions between the stored states.

Edit for second question:

You configure the constraint database by setting the folder path as a ros parameter:

<param name="move_group/constraint_approximations_path" value="$(find package)/cadb"/>

I believe any constraint approximation database file you store in that folder will be considered at runtime.

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Originally posted by xibeisiber with karma: 137 on 2021-11-03

This answer was ACCEPTED on the original site

Post score: 0

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Original comments

Comment by xibeisiber on 2021-11-09:
Thanks for your answer. I managed to do this by setting the folder path and combining the manifest info of two databases into one manifest file.