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Use the household_objects_database remotely from a Willow Garage server

Description: Shows how to use the household_object_database remotely, by using the services provided by a database wrapper node running on a Willow Garage server.

Tutorial Level: BEGINNER

All you have to do to use the household_objects_database remotely is to launch the following file on your local machine, after starting a ROS master:

roslaunch household_objects_database objects_database_remote_client.launch

This will tell your ROS master that the database services should be sent to a remote ROS master running on a server at Willow Garage. The following services get remapped:

• /objects_database_node/database_grasp_planning

• /objects_database_node/get_model_description

• /objects_database_node/get_model_list

• /objects_database_node/get_model_mesh

Testing and troubleshooting

To test that this is working, try the following command:

rosservice call /objects_database_node/get_model_list REDUCED_MODEL_SET

The reply should be along the lines of:

return_code: 
  code: -1
model_ids: [18800, 18798, 18665, 18685, 18802, 18746, 18766, 18783, 18765, 18791, 18799, 18693, 18744, 18807, 18808, 18699, 18691]

If instead you get an error like:

ERROR: Unable to communicate with service [/objects_database_node/get_model_description], address [rosrpc://grasp.willowgarage.com:15432]

this might mean that either your machine does not have access to the Internet, or the remote server is down. Please send an email to the ros-users list informing us of the problem.

To get all the objects use the following command:

rosservice call /objects_database_node/get_model_list ""

Advanced testing

To test that the grasp planning service is working, you can use the following command:

rosservice call /objects_database_node/database_grasp_planning "{arm_name: right_arm, target: {type: 1, model_pose:{model_id: 18744 } } }"

You should get back a long lists of grasps, all of them looking something like this:

    pre_grasp_posture: 
      header: 
        seq: 0
        stamp: 
          secs: 0
          nsecs: 0
        frame_id: ''
      name: ['r_gripper_l_finger_joint', 'r_gripper_r_finger_joint', 'r_gripper_r_finger_tip_joint', 'r_gripper_l_finger_tip_joint']
      position: [0.52359900000000004, 0.52359900000000004, 0.52359900000000004, 0.52359900000000004]
      velocity: []
      effort: []
    grasp_posture: 
      header: 
        seq: 0
        stamp: 
          secs: 0
          nsecs: 0
        frame_id: ''
      name: ['r_gripper_l_finger_joint', 'r_gripper_r_finger_joint', 'r_gripper_r_finger_tip_joint', 'r_gripper_l_finger_tip_joint']
      position: [0.39125900000000002, 0.39125900000000002, 0.39125900000000002, 0.39125900000000002]
      velocity: []
      effort: [10000.0, 10000.0, 10000.0, 10000.0]
    grasp_pose: 
      position: 
        x: -0.121641
        y: 0.09348
        z: 0.125899
      orientation: 
        x: -0.919996
        y: 0.336396
        z: 0.187844
        w: 0.0718267