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Version: 9

objectives Values

Objectives and Behaviors Configuration​

example_robot_ws Checkpoint

If you are following this guide with example_robot_ws, your workspace should look like branch step6. We are now editing example_robot_mock config.yaml.

objectives​

Type: object (required)

Description: Configuration for MoveIt Pro Behaviors, Objectives, and waypoints.

objectives.behavior_loader_plugins​

Type: object (required)

Description: Dictionary mapping plugin names to lists of Behavior loader classes.

Common "core" behavior loaders include:

  • CoreBehaviorsLoader: Basic motion and control Behaviors
  • MTCCoreBehaviorsLoader: MoveIt Task Constructor Behaviors
  • VisionBehaviorsLoader: Computer vision and perception Behaviors
  • MPCBehaviorsLoader: MuJoCo Model Predictive Control (MPC) Behaviors
  • ConverterBehaviorsLoader: Packing, unpacking, and transforming messages via Behaviors
  • MujocoBehaviorsLoader: Interacting with the MuJoCo simulation via Behaviors
Add out-of-box Behaviors to your example_robot_mock/config/config.yaml behavior_loader_plugins
# Configuration for loading behaviors and objectives.
# [Required]
objectives:
  # List of plugins for loading custom behaviors.
  # [Required]
  behavior_loader_plugins:
    # This plugin will load the core MoveIt Pro Behaviors.
    # Add additional plugin loaders as needed.
    core:
      - "moveit_pro::behaviors::CoreBehaviorsLoader"
      - "moveit_pro::behaviors::MTCCoreBehaviorsLoader"
      - "moveit_pro::behaviors::VisionBehaviorsLoader"
      - "moveit_pro::behaviors::MPCBehaviorsLoader"
      - "moveit_pro::behaviors::ConverterBehaviorsLoader"
      - "moveit_pro::behaviors::MujocoBehaviorsLoader"

When you use the MoveIt Pro UI to generate custom Behavior boilerplate, it will also add "BehaviorsLoader" boilerplate that should be linked here.

objectives.objective_library_paths​

Type: object (required)

Description: Dictionary mapping library names to package locations containing Objective XML files.

Add out-of-box Objectives to your example_robot_mock/config/config.yaml objective_library_paths
objectives:
  ...
  # Specify source folder for objectives
  # [Required]
  objective_library_paths:
    core_objectives:
      package_name: "moveit_pro_objectives"
      relative_path: "objectives/core"
    motion_objectives:
      package_name: "moveit_pro_objectives"
      relative_path: "objectives/motion"
    perception_objectives:
      package_name: "moveit_pro_objectives"
      relative_path: "objectives/perception"
    mujoco_objectives:
      package_name: "moveit_pro_objectives"
      relative_path: "objectives/mujoco"
    visualization_objectives:
      package_name: "moveit_pro_objectives"
      relative_path: "objectives/visualization"

Each objective library entry requires:

  • package_name (string): ROS package containing objectives
  • relative_path (string): Path within the package to Objectives directory

Custom Objectives​

As motivated in our Robot Config Inheritance and Objective Package best practices, you should include objective_library_paths entries for

  1. Objectives that will be shared across robot configs, e.g. your applications.
  2. "Core" Objective overriding specific to a particular robot config, e.g. the specifics of how the simulator/driver handles gripper commands.
Add custom entries to your example_robot_mock/config/config.yaml objective_library_paths

In the interest of time, we will not be creating a separate repository and package for my_applications_package, so leave that entry commented out for now.

objectives:
  ...
  objective_library_paths:
    ...
    # my_applications:
    #   package_name: "my_applications_package"
    #   relative_path: "objectives"
    sim_overrides:
      package_name: "example_robot_mock"
      relative_path: "objectives"
note

The last entry in the objective_library_paths list will be the location newly created Objectives in the MoveIt Pro UI are saved to.

Overriding "Core" Objectives​

You can override an Objective by placing an Objective with the same name in a library lower in the objectives.objective_library_paths list.

Teleoperation Requirements​

The moveit_pro_objectives "core" definitions for Open Gripper and Close Gripper simply return "Success". You should implement these Objectives according to the expected behavior for your gripper type.

Create src/example_robot_mock/objectives/open_gripper.xml Objective
<?xml version="1.0" ?>
<root BTCPP_format="4" main_tree_to_execute="Open Gripper">
  <!--//////////-->
  <BehaviorTree
    ID="Open Gripper"
    _description="Open the gripper"
    _favorite="false"
  >
    <Control ID="Sequence" name="root">
      <Action
        ID="MoveGripperAction"
        gripper_command_action_name="/robotiq_gripper_controller/gripper_cmd"
        position="0.05"
        timeout="15.000000"
      />
    </Control>
  </BehaviorTree>
  <TreeNodesModel>
    <SubTree ID="Open Gripper">
      <MetadataFields>
        <Metadata subcategory="Grasping" />
      </MetadataFields>
    </SubTree>
  </TreeNodesModel>
</root>
Create src/example_robot_mock/objectives/close_gripper.xml Objective
<?xml version="1.0" encoding="UTF-8" ?>
<root BTCPP_format="4" main_tree_to_execute="Close Gripper">
  <BehaviorTree
    ID="Close Gripper"
    _description="Close the gripper"
    _favorite="false"
  >
    <Control ID="Sequence" name="root">
      <Action
        ID="MoveGripperAction"
        gripper_command_action_name="/robotiq_gripper_controller/gripper_cmd"
        position="0.7929"
        timeout="15.000000"
      />
    </Control>
  </BehaviorTree>
  <TreeNodesModel>
    <SubTree ID="Close Gripper">
      <MetadataFields>
        <Metadata subcategory="Grasping" />
      </MetadataFields>
    </SubTree>
  </TreeNodesModel>
</root>

objectives.waypoints_file​

Type: object (required)

Description: Location of the waypoints YAML file for named robot poses.

objectives:
  waypoints_file:
    package_name: "example_robot_mock"
    relative_path: "waypoints/waypoints.yaml"
  • package_name (string): ROS package containing waypoints file
  • relative_path (string): Path within package to waypoints file
step7 Checkpoint

Your example_robot_ws workspace should now look like branch step7.