Move It! polar robot configuration not moving second joint

Question

Hi all! I'm fighting to create a polar robot configuration with Move It.

The polar robot has 3 joints: rotational, rotational and prismatic.

Polar robot http://www.robotpark.com/academy/PG/Spherical-Robots-Robotpark.png

I have model it in a xacro file and can move it with problems in Rviz with fake controllers.

Rviz simulation

Here is the xacro file of the robot (be care to uncomment the lines for the joint with the world) link

And for launch it, this is the command:

roslaunch arm_description rviz.launch

Then I follow the MoveIt! tutorial for a custom robot (link) and generate all the files correctly, but as you can see in the next video, it only moves the first joint (rotational) and the third joint (prismatic), but not the second one (rotational). Video

And for launch it, this is the command:

roslaunch rrp_moveit demo.launch

I would apreciate some help in trying to fix this problem.

Kinds regards, Jorge

EDIT: This is the workspace for all the project.

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Originally posted by jdeleon on ROS Answers with karma: 133 on 2018-10-01

Post score: 0

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Original comments

Comment by gvdhoorn on 2018-10-02:
Cross-post of ros-planning/moveit#1074.

Answer 1

The solution is explained in ros answer #95626

The problem is that the arm needs to have, at least 6DOF for the solver to find the solution.

The solution is to add the next line in kinematics.yaml file:

position_only_ik: True

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Originally posted by jdeleon with karma: 133 on 2018-10-02

This answer was ACCEPTED on the original site

Post score: 0

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Original comments

Comment by nguyentuMTA on 2019-04-03:
I using position_only_ik: True for 3 dof custom arm but with that when I use the interactive marker only 1st 2nd joint can rotate the 3rd can't move so the robot can reach all the its own workspace Does anyone know about this