Overview

This package contains many useful states and state machines for commanding a Care-O-bot.

State Machine Usage and Documentation

ApproachPoses

Approaches a pose or a list of poses and checks the accessibility for moving to these poses beforehand with the services provided by cob_map_accessibility_analysis. To use this state machine the map analysis has to be started first:

roslaunch cob_map_accessibility_analysis map_accessibility_analysis.launch

Input keys

goal_poses

Array of geometry_msgs/Pose2D objects, each describing a goal position of the robot.

goal_pose_application

Defines the mode of usage of the provided goal poses:

• 'visit_all_in_order' (commands the robot to all poses in the provided order),
  'visit_all_nearest' (commands the robot to all poses using the closest next pose each time),
  'use_as_alternatives' (visits the first pose of the list that is reachable).
  

Independent of the mode, this state machine always terminates once a goal position could be reached, so for the visit_all modes the state_machine has to be called until 'not_reached' is returned from 'SELECT_GOAL'. Internally, the remaining, not yet visited states, are stored in the list 'goal_poses_verified' for the visit_all modes.

new_computation_flag

If True, the provided list of poses is examined for accessibility, else the old list from userdata.goal_poses_verified is used again. This variable is used by the visit_all modes, which work on the already existing list of goal poses after the first call.

Output_keys

new_computation_flag

see above

ApproachPerimeter

Approaches a pose on the perimeter of a circle and checks the accessibility for moving to this pose beforehand with the services provided by cob_map_accessibility_analysis. To use this state machine the map analysis has to be started first:

roslaunch cob_map_accessibility_analysis map_accessibility_analysis.launch

Input keys

center

Pose2D defining the center point of the circle to be visited. You may provide an orientation angle as well, which defines the "viewing direction" of the target.

radius

Double value of the radius of the circle.

rotational_sampling_step

Double value of the angular sampling step with in [rad] of goal poses on the perimeter of the circle.

goal_pose_selection_strategy

Defines which of the possible poses on the circle shall be preferred:

• 'closest_to_target_gaze_direction' (commands the robot to the pose which is closest to the target's viewing direction, useful e.g. for living targets),
  'closest_to_robot' (commands the robot to the pose closest to the current robot position, useful e.g. for inspecting a location).
  

Independent of the mode, this state machine always terminates once a goal position could be reached, however, to visit multiple locations on the same circle the state_machine has to be called with 'new_computation_flag' set to False and an appropriate 'invalidate_other_poses_radius' until 'not_reached' is returned from 'SELECT_GOAL'. Internally, the remaining, not yet visited states, are stored in the list 'goal_poses_verified'.

invalidate_other_poses_radius

Within a circle of this radius (in [m]) around the current goal pose all other valid poses become deleted from userdata.goal_poses_verified so that the next accessible pose a a certain minimum distance from the current goal pose.

new_computation_flag

If True, the poses on the defined circle are examined for accessibility, else the old list from userdata.goal_poses_verified is used again. This variable is used to command the robot to different perspectives on the same goal, which are computed at the first call of this state machine.

Output_keys

new_computation_flag

see above

ApproachPolygon

Approaches one or multiple poses on the perimeter of an arbitrary polygon and checks the accessibility for moving to this pose beforehand with the services provided by cob_map_accessibility_analysis. To use this state machine the map analysis has to be started first:

roslaunch cob_map_accessibility_analysis map_accessibility_analysis.launch

Input keys

polygon

cob_3d_mapping_msgs/Shape defining the polygon whose perimeter is to be visited by the robot.

invalidate_other_poses_radius

Within a circle of this radius (in [m]) around the current goal pose all other valid poses become deleted from userdata.goal_poses_verified so that the next accessible pose a a certain minimum distance from the current goal pose.

new_computation_flag

If True, the poses on the defined circle are examined for accessibility, else the old list from userdata.goal_poses_verified is used again. This variable is used to command the robot to different perspectives on the same goal, which are computed at the first call of this state machine. This state machine always terminates once a goal position could be reached, however, to visit multiple locations around the same polygon the state_machine has to be called with 'new_computation_flag' set to False and an appropriate 'invalidate_other_poses_radius' until 'not_reached' is returned from 'SELECT_GOAL'. Internally, the remaining, not yet visited states, are stored in the list 'goal_poses_verified'.

Output_keys

new_computation_flag

see above