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Calculating a NextBestView

Description: In this tutorial we will set the robot position and determine a NextBestView

Tutorial Level: BEGINNER

Description

In this tutorial we will set the robot position and determine a NextBestView

Setup

Do the previous tutorial (http://wiki.ros.org/asr_next_best_view/AsrNextBestViewSetPointCloud)

Tutorial

First we set the robot position with:

rostopic pub /initialpose geometry_msgs/PoseWithCovarianceStamped "header:
  seq: 0
  stamp:
    secs: 0
    nsecs: 0
  frame_id: 'map'
pose:
  pose:
    position: {x: -0.52, y: -0.39, z: 0.0}
    orientation: {x: 0.0, y: 0.0, z: 0.17919106, w: 0.98381429}
  covariance: [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0,
    0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0,
    0.0, 0.0, 0.0, 0.0, 0.0, 0.0]" --once

the position is the center of the robot base, while the orientation is the rotation of the robot base (in this case it's ~20 degree).

Then we send the current robot pose to the next_best_view node:

rosservice call /nbv/set_init_robot_state "robotState: {pan: 0.0, tilt: 0.0, rotation: 0.35, x: -0.52, y: -0.39}"

We didn't modify the ptu, so the ptu position is (0, 0)

Now we get our current camera pose by calling the robot model service to display the current camera frustum:

rosservice call /asr_robot_model_services/GetCameraPose "{}"

  pose:
    position:
      x: -0.505544160413
      y: -0.428367026231
      z: 1.47388
    orientation:
      x: 0.0
      y: 0.0
      z: 0.17919106061
      w: 0.983814293349

Now we send this pose back to the next_best_view node to visualize the frustum (keep in mind we didn't modify the PTU):

rosservice call /nbv/trigger_frustum_visualization "current_pose:
  position:
    x: -0.50
    y: -0.42
    z: 1.47
  orientation:
    x: 0.0
    y: 0.0
    z: 0.179
    w: 0.983"

Finally we do the GetNextBestView call using the camera pose

rosservice call /nbv/next_best_view "current_pose:
  position:
    x: -0.50
    y: -0.42
    z: 1.47
  orientation:
    x: 0.0
    y: 0.0
    z: 0.179
    w: 0.983"

found: True
object_type_name_list: ['Cup']
resulting_pose:
position:
  x: -0.5
  y: -0.585767805576
  z: 1.47000002861
orientation:
  x: -0.115216434002
  y: 0.243114843965
  z: 0.412469029427
  w: 0.870338857174
robot_state:
  pan: 0.331612557173
  tilt: -0.599535286427
  rotation: 0.553517401218
  x: -0.464413404465
  y: -0.59638440609
utility: 0.857888042927
utility_normalization: 0.857888042927
inverse_costs: 138.182449341
base_translation_inverse_costs: 0.998762726784
base_rotation_inverse_costs: 0.327448785305
ptu_movement_inverse_costs: 0.0749999880791
recognition_inverse_costs: 0.0

The result contains the camera pose and robot state of the NextBestView and some stats about the view rating. We can now display the found view using:

rosservice call /nbv/trigger_frustum_visualization "current_pose:
  position:
    x: -0.50
    y: -0.585
    z: 1.47
  orientation:
    x: -0.115
    y: 0.243
    z: 0.412
    w: 0.870"

the old view/start view can be shown using:

rosservice call /nbv/trigger_old_frustum_visualization "current_pose:
  position:
    x: -0.50
    y: -0.42
    z: 1.47
  orientation:
    x: 0.0
    y: 0.0
    z: 0.179
    w: 0.983"