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Manipulator with multiple tip_links in SRDF.

I have a robot manipulator with one effector and two tip links (tool0,tool1). My tool has 4 fingers mounted in 2 pairs in a 90-degree angle. So there is no actuated joint between those two tip links, both finger pairs are actuated by the same gripper.

What I want to achieve is to make planning to both tip links possible in MoveIt. I managed to get both displayed in RViz by specifying 2 end-effectors. However, I get some complaints on the console output.

[ WARN] [1571994439.576069188]: Could not identify parent group for end-effector 'gripper0'
[ WARN] [1571994439.576094887]: Could not identify parent group for end-effector 'gripper1'
[ERROR] [1571994439.576049115]: Group 'manipulator' was specified as parent group for end-effector 'gripper0' but it does not include the parent link 'tool0'
[ERROR] [1571994439.576085790]: Group 'manipulator' was specified as parent group for end-effector 'gripper1' but it does not include the parent link 'tool1'

My SRDF looks as follows.

<group name="manipulator">
<chain base_link="borunte_stand_link" tip_link="flange" />
</group>
<group name="gripper0">
<joint name="flange-tool0"/>
<link name="tool0" />
</group>
<group name="gripper1">
<joint name="flange-tool1"/>
<link name="tool1" />
</group>
<!--END EFFECTOR: Purpose: Represent information about an end effector.-->
<end_effector name="gripper0" parent_link="tool0" group="gripper0" parent_group="manipulator"/>
<!--<end_effector name="gripper0" parent_link="flange" group="gripper0" parent_group="manipulator" />-->
<end_effector name="gripper1" parent_link="tool1" group="gripper1" parent_group="manipulator" />

Here is how it looks in RViz

image description

Any ideas on how to make this work correctly?

Manipulator with multiple tip_links in SRDF.

I have a robot manipulator with one effector and two tip links (tool0,tool1). My tool has 4 fingers mounted in 2 pairs in a 90-degree angle. So there is no actuated joint between those two tip links, both finger pairs are actuated by the same gripper.

What I want to achieve is to make planning to both tip links possible in MoveIt. I managed to get both displayed in RViz by specifying 2 end-effectors. However, I get some complaints on the console output.

[ WARN] [1571994439.576069188]: Could not identify parent group for end-effector 'gripper0'
[ WARN] [1571994439.576094887]: Could not identify parent group for end-effector 'gripper1'
[ERROR] [1571994439.576049115]: Group 'manipulator' was specified as parent group for end-effector 'gripper0' but it does not include the parent link 'tool0'
[ERROR] [1571994439.576085790]: Group 'manipulator' was specified as parent group for end-effector 'gripper1' but it does not include the parent link 'tool1'

My SRDF looks as follows.

<group name="manipulator">
<chain base_link="borunte_stand_link" tip_link="flange" />
</group>
<group name="gripper0">
<joint name="flange-tool0"/>
<link name="tool0" />
</group>
<group name="gripper1">
<joint name="flange-tool1"/>
<link name="tool1" />
</group>
<!--END EFFECTOR: Purpose: Represent information about an end effector.-->
<end_effector name="gripper0" parent_link="tool0" group="gripper0" parent_group="manipulator"/>
<!--<end_effector name="gripper0" parent_link="flange" group="gripper0" parent_group="manipulator" />-->
<end_effector name="gripper1" parent_link="tool1" group="gripper1" parent_group="manipulator" />

Here is how it looks in RViz

image description

Any ideas on how to make this work correctly?

NOTE: I noticed that I can make one of the error messages go away by specifying tool0 as the tip_link in the manipulator chain. However, adding and the additional link tool1 or joint breaks the kinematic chain.