ROS Resources: Documentation | Support | Discussion Forum | Index | Service Status | ros @ Robotics Stack Exchange
Ask Your Question
0

How to setup planning group moveit for dual arm

asked 2021-08-21 02:45:03 -0500

peng cheng gravatar image

Hi all, I had a self-made dual arm system, want to set up the moveit configuration.

I follow the advice to configure it like this.

<group name="left_arm">
    <joint name="left_arm_base_joint" />
   ...
    <joint name="left_fake_end_joint" />
    <chain base_link="left_arm_base_link" tip_link="left_fake_end" />
</group>
<group name="right_arm">
    <joint name="right_arm_base_joint" />
    ...
    <joint name="right_fake_end_joint" />
    <chain base_link="right_arm_base_link" tip_link="right_fake_end" />
</group>
<group name="both_arms">
    <group name="left_arm" />
    <group name="right_arm" />

But I got this error

 [ERROR] []: Group 'both_arms' is not a chain
 [ERROR] []: Kinematics solver of type 'kdl_kinematics_plugin/KDLKinematicsPlugin' could not be initialized for group 'both_arms'
 [ERROR] []: Kinematics solver could not be instantiated for joint group both_arms.

And also I tried the below configuration, as pr2 set each arm as a chain, but also got the same error.

I did a test on pr2, when I choosing arms, it will show two interactive marker for both arms. But in my case, I don't have any, but if I choose right_arm or left_arm, there will be one interactive marker for each arm. This is my srdf, quite similar to the pr2's.

<group name="left_arm">
    <chain base_link="body_link" tip_link="left_arm_link4" />
</group>
<group name="right_arm">
    <chain base_link="body_link" tip_link="right_arm_link4" />
</group>
<group name="both_arms">
    <group name="left_arm" />
    <group name="right_arm" />
</group>

I don't know how pr2 setup arms plan group, it would be very appreciated that someone can help me, thanks!

edit retag flag offensive close merge delete

Comments

Is there nothing else that is different between your robot and the PR2? What if you add the joints to your two arm groups, like in the PR2 URDF?

fvd gravatar image fvd  ( 2021-08-25 19:56:06 -0500 )edit

Thanks! It is the same result when I change to joints. The Kinematic Solver for the "both_arms" group is set to None, pr2 also does this if I am correct. My question is how this None Kinematic Solver do the motion plan, or it does the motion plan for "left_arm" and "right_arm" subgroup separately instead? I have no idea now, quite confused to me.

peng cheng gravatar image peng cheng  ( 2021-08-28 06:45:21 -0500 )edit

1 Answer

Sort by ยป oldest newest most voted
0

answered 2021-09-08 08:18:11 -0500

peng cheng gravatar image

I don't know why, but after I added an end effector for each arm, two interactive markers appear. So problem solved.

edit flag offensive delete link more

Comments

Would you like to share your SRDF file?

ColorJ gravatar image ColorJ  ( 2022-06-12 22:00:56 -0500 )edit

Question Tools

2 followers

Stats

Asked: 2021-08-21 02:45:03 -0500

Seen: 220 times

Last updated: Sep 08 '21