Gripper Grasp Planner Cluster - gripper model changes during grasp testing

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Hi all,

I'm testing pr2_gripper_grasp_planner_cluster, which plans grasps on PointClouds as part of the Tabletop Manipulation pipeline. This node requires a configuration file, specifying a model of your gripper & the grasping area.

I'm running the grasp planner configured for side-grasps only, & displaying the gripper model. It fails to find a valid grasp, so my model needs tweaking, but strangely the planner/Rviz is mangling the model!

Each time I run the planner, the gripper model is shown in Rviz but with the pieces of the gripper moved in relation to each other! So it's not going to find a solution if it's mangling the model. Or maybe this is just a problem with the visualization markers in Rviz.

Please see pictures & config file below.

Many thanks,
David.

As a reference, this is the grasping model of the PR2 gripper:
(Gripper is blue, grasp area is yellow)

I'm trying to simulate a simplified human hand.
Imagine your thumb points downwards, and you approach an object with your fingers pointing towards it (x-direction). Like grasping a book from a bookshelf.
(The gripper is shown in green, with the small "thumb" pointing out from the screen, and the "fingers" would point to the right if they were shown. The grasping area is blue.)

These pictures are 3 runs of the grasp planner. Each time the blocks of the gripper model are moved around in relation to each other.

Configuration file from cluster grasp planner:

# Gripper area
gripper_boxes: [ [[0.000, -0.020, -0.053], [0.120, 0.044, 0.03125]], [[0.000, -0.029, 0.001], [0.054, -0.020, 0.051]], [[0.0065, -0.059, 0.00875], [0.0415, -0.029, 0.03125]], [[0.040, -0.089, 0.00875], [0.080, -0.067, 0.03125]] ]

# Grasp area
space_boxes: [[ [[0.054, -0.067, 0.013], [0.120, -0.020, 0.023]] ]]

joint_names: 
  right_arm: ['hand_r_thumb_joint', 'hand_r_index_1_joint', 'hand_r_index_2_joint', 'hand_r_index_3_joint', 'hand_r_middle_1_joint', 'hand_r_middle_2_joint', 'hand_r_middle_3_joint']
  left_arm: ['hand_l_thumb_joint', 'hand_l_index_1_joint', 'hand_l_index_2_joint', 'hand_l_index_3_joint', 'hand_l_middle_1_joint', 'hand_l_middle_2_joint', 'hand_l_middle_3_joint']

# thumb is downwards
pregrasp_joint_angles:
  right_arm: [1.5, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0 ]
  left_arm: [1.5, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0 ]

# all closed
grasp_joint_angles: 
  right_arm: [1.5, 1.5, 1.5, 1.5, 1.5, 1.5, 1.5 ]
  left_arm: [1.5, 1.5, 1.5, 1.5, 1.5, 1.5, 1.5 ]

pregrasp_joint_efforts:
  right_arm: [100.0, 100.0, 100.0, 100.0, 100.0, 100.0, 100.0 ]
  left_arm: [100.0, 100.0, 100.0, 100.0, 100.0, 100.0, 100.0 ]

grasp_joint_efforts:
  right_arm: [50.0, 50.0, 50.0, 50.0, 50.0, 50.0, 50.0 ]
  left_arm: [50.0, 50.0, 50.0, 50.0, 50.0, 50.0, 50.0 ]