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Extract just the path (in coordinates) instead of trajectories from MoveIt!

Hello all,

From what i know, when using OMPL.app (Graphical User Interface to OMPL), we can actually "print" a path to an output file by using 

 ompl::geometric::PathGeometric::printAsMatrix()

And from MoveIt!, movegroup pulls all the individual components together to provide "cmdvel" (geometrymsgs/Twist). My question is, is it possible to print only the path from movegroup and how?

Any help would be greatly appreciated. Thank you.

Asked by Wen Xin on 2017-02-23 22:15:38 UTC

Comments

MoveIt! does not produce Twist messages. It only generates RobotTrajectory instances, which are ultimately typically transformed into a JointTrajectory msg. Are you sure you're not confusing move_group with move_base? The latter is from the ROS Navigation stack.

Asked by gvdhoorn on 2017-02-24 01:41:53 UTC

@gvdhoorn Thanks for the explanation. If i were to extract just the path (in coordinates) instead of trajectories from MoveIt!, will it be possible?

Asked by Wen Xin on 2017-02-24 02:18:01 UTC

I don't know of any functionality (on the user side) in MoveIt that would let you print out trajectories like this.

What you could perhaps do is subscribe to the FollowJointTrajectory topic(s) or use rostopic echo .. > my_file.yaml.

Asked by gvdhoorn on 2017-02-24 02:48:27 UTC

Also, could I ask you to tell us what the status is of #q255217 and #q254927?

Asked by gvdhoorn on 2017-02-24 02:49:26 UTC

@gvdhoorn Alright, thanks for clearing up my doubts! and yes, i will update the status of #q255217 and #q254927 as soon as possible.

Asked by Wen Xin on 2017-02-24 03:38:53 UTC

Joint trajectories are composed of joint trajectory points, in which the joint positions for each point along the trajectory are provided. With this you can compute FK to obtain the Cartesian position for each joint trajectory point.

Asked by JoshMarino on 2017-02-24 08:34:05 UTC

Answers