MoveIt-PDDL: Task and Motion Planning in ROS 2

A ROS 2 package demonstrating task and motion planning (TAMP) on a Franka Emika Panda manipulator. The robot solves the Tower of Hanoi puzzle by combining symbolic task planning with geometric motion planning.

The symbolic planning problem is modeled in PDDL and solved using Fast Downward. Each action is then executed using MoveIt 2 and the MoveIt Task Constructor (MTC), which computes inverse kinematics, collision-free motion plans, and gripper actions.

Package Overview

This repository contains two primary ROS nodes:

• hanoi_planner – Generates a symbolic task plan by invoking the Fast Downward PDDL planner.
• hanoi_mtc_executor – Converts each symbolic action into a MoveIt Task Constructor task, computes IK and collision-free motion plans, and executes the resulting trajectory.

Pipeline

PDDL Problem
    ↓
Fast Downward
    ↓
Symbolic Plan
    ↓
MoveIt Task Constructor
    ↓
IK & Motion Planning
    ↓
Robot Execution

Requirements

1. MoveIt 2

This package requires a working MoveIt 2 installation. Build and source a MoveIt workspace before building this package. See the MoveIt 2 installation guide for setup instructions.

2. Trimesh

Used to generate the STL meshes for the Tower of Hanoi disks.

pip install trimesh

3. Fast Downward

Used to solve the PDDL task planning problem. Installing from source is recommended. The path to your Fast Downward installation must be provided as a ROS parameter when running the planner.

Usage

1. Generating Disk Meshes

The package uses procedurally generated STL meshes for the Hanoi disks. Before building the package, generate meshes for the desired number of disks:

python scripts/generate_disk_meshes.py --disks 4

The generated meshes will be written to the meshes/ directory.

2. Build the Workspace

Make sure your MoveIt 2 workspace has been sourced before building.

colcon build
source install/local_setup.bash

3. Launch MoveIt 2

Start RViz, move_group, and the required controllers:

ros2 launch moveit_hanoi demo.launch.py

4. Launching the MTC Executor

Start the MoveIt Task Constructor execution node:

ros2 launch moveit_hanoi hanoi_demo.launch.py

5. Generate a Task Plan

Run the PDDL planner, providing the path to your Fast Downward installation via the fast_downward_path ROS parameter.

ros2 run moveit_hanoi hanoi_planner.py --ros-args \
  -p fast_downward_path:=/path/to/fast-downward

Replace /path/to/fast-downward with the root directory of your Fast Downward installation.