The Planner Command

Table of Contents

• Input
  • Start and Goal Scenes
  • Task Domain
  • Domain Scripts
• Output
  • Plan Files
  • Visualization
• Examples
• Options Summary

This package provides a shell command to invoke the task-motion planner.

Input

Start and Goal Scenes

• Start and goal scenes may be specified as Amino Scene Files or as ROS URDF.
• The start scene includes the robot and all object in the environment.
• The goal scene defines target locations for (usually a subset of) environment objects.

Task Domain

• The task domain is specified in the Planning Domain Definition Language (PDDL).
• Task facts – PDDL Objects, start state, goal state, etc. – are inferred from the start and goal scenes.

Domain Scripts

• The domain-specific mapping from scenes to task state and task operators to motion planning problems is specified via functions defined in user-provided domain script files
• Scripts may be written in Python or Common Lisp. Note, however, that Python scripts cannot use extension modules.

• See also

  TMKit Domain Semantics API (Python)

Output

Plan Files

• Plans are recorded in as TMSMT in a plain-text, line-based format.

• See also

  Plan Files

Visualization

• When the planner is give the --gui flag, it will visualize the planning scene and the computed task-motion plan.
• Previously saved plan files can be later reloaded and visualized with the --load-plan=PLAN_FILE parameter.

Examples

The demo directory in the source distribution provides several example domains and use cases for the planner command. A few of these cases are described in detail here.

Pure Task Planning

When given only the task domain and facts, the planner command will compute a pure task plan. Using the blocksworld domain included in the source distribution, call the planner as:

tmsmt demo/domains/blocksworld/blocks-domain.pddl \
      demo/domains/blocksworld/sussman-anomaly.pddl

Task-Motion Planning

When loading scenes from URDF, it is necessary to set the ROS_PACKAGE_PATH environment variable because URDF external files such as meshes via ROS packages.

# Assuming you have install ROS indigo under /opt
export ROS_PACKAGE_PATH=/opt/ros/indigo/share

The following command will compute a task-motion plan for the Baxter robot and output the plan to baxter-sussman.tmp.

tmsmt package://baxter_description/urdf/baxter.urdf \
      sussman-0.robray \
      allowed-collision.robray \
      -g sussman-1.robray  \
      -d domain.pddl \
      -o baxter-sussman.tmp

The following command will load and visualize the previously computed task-motion plan from the file baxter-sussman.tmp.

tmsmt package://baxter_description/urdf/baxter.urdf \
      sussman-0.robray \
      allowed-collision.robray \
      -i baxter-sussman.tmp

Options Summary

See also

Man Page