ROS Resources: Documentation | Support | Discussion Forum | Index | Service Status | Q&A
Ask Your Question

Move It! polar robot configuration not moving second joint

asked 2018-10-01 17:14:47 -0600

jdeleon gravatar image

updated 2018-10-01 17:18:01 -0600

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

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.

edit retag flag offensive close merge delete


gvdhoorn gravatar image gvdhoorn  ( 2018-10-02 02:55:58 -0600 )edit

1 Answer

Sort by ยป oldest newest most voted

answered 2018-10-02 11:13:48 -0600

jdeleon gravatar image

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
edit flag offensive delete link more


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

nguyentuMTA gravatar image nguyentuMTA  ( 2019-04-03 21:27:34 -0600 )edit

Your Answer

Please start posting anonymously - your entry will be published after you log in or create a new account.

Add Answer

Question Tools


Asked: 2018-10-01 17:14:47 -0600

Seen: 445 times

Last updated: Oct 02 '18