🌹🌹🌹 WARDE 🌹🌹🌹

Wandering Autonomous Robot Donde Estas

The Great MCE550 Project

Warde is a fully-integrated ROS 2-based behavior tree demo that autonomously roams, finds beer cans, picks them up, and places them into a drop-box. It leverages Gazebo simulation, BehaviorTree.CPP, ROS 2 actions/services, and a simple tagging mechanism to avoid revisiting the same target.

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Quick Start

1. Prerequisites

• Ubuntu 22.04 LTS
• ROS 2 Humble Hawksbill (desktop)
• Docker & Docker Compose (optional, for containerized runs)
• colcon build tools

2. ROS 2 Installation

# Setup locale
sudo locale-gen en_US en_US.UTF-8
sudo update-locale LC_ALL=en_US.UTF-8 LANG=en_US.UTF-8

# Add ROS 2 repo and keys
sudo apt update && sudo apt install -y curl gnupg2 lsb-release
sudo curl -sSL https://raw.githubusercontent.com/ros/rosdistro/master/ros.asc   | sudo apt-key add -
sudo sh -c 'echo "deb http://packages.ros.org/ros2/ubuntu $(lsb_release -cs) main"   > /etc/apt/sources.list.d/ros2.list'
sudo apt update

# Install ROS 2 Humble (Desktop)
sudo apt install -y ros-humble-desktop

# Install build tools and dependencies
sudo apt install -y python3-colcon-common-extensions python3-rosdep

# Initialize rosdep
sudo rosdep init
rosdep update

Load ROS 2 environment in your ~/.bashrc:

echo "source /opt/ros/humble/setup.bash" >> ~/.bashrc
source ~/.bashrc

3. Clone & Build the Workspace

cd ~/Desktop/MCE550/warde
# Ensure 'src/' contains: robot_description, spawn_tools, warde_bt, etc.
rosdep install --from-paths src --ignore-src -r -y
colcon build --symlink-install
source install/setup.bash

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Launching the System

We provide a single launch file to start Gazebo + RViz, the nav server, both spawners, and the behavior tree:

ros2 launch warde_bt launch_all.launch.py   world:=$(ros2 pkg prefix robot_description)/models/myWorld/boxes_world.sdf   use_sim_time:=true   rviz_config_file:=$(ros2 pkg prefix robot_description)/rviz/sim.config.rviz

Behind the scenes, this does:

1. ros2 launch robot_description launch_sim.launch.py ...
2. ros2 run robot_nav navigate_node
3. ros2 run spawn_tools spawn_box_node
4. ros2 run spawn_tools spawn_beer_node
5. ros2 run warde_bt warde_bt_main

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Features & Workflow

1. Wandering mode: random exploration when no beer is found or after placement.
2. Beer detection: TF-listener scans /tf for frames named beer*.
3. Closest-beer selection: picks the nearest beer frame.
4. Tagged beers: once collected, beer frames get “tagged” and ignored on future loops.
5. Precise approach: robot stops 1 m from beer or from the front face of the box.
6. Behavior Tree: mission sequence built with BehaviorTree.CPP:
   • ConditionBoxPresent, ConditionBeerPresent
   • ActionGetClosestBeer, ActionNavigate, ActionManipulate
   • Fallback to wandering on any failure, loop indefinitely.

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Containerized Run (Docker)

1. Build the Docker image:

   docker build -t warde_ws:humble .

2. Run it (with X11 forwarding & host networking):

   xhost +local:root
   docker run -it --rm       --net=host       -e DISPLAY=$DISPLAY       -v /tmp/.X11-unix:/tmp/.X11-unix       warde_ws:humble

3. Alternatively, build and start all services with Docker Compose:

   xhost +local:root && docker-compose up --build

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Accessing Services

You can call any ROS 2 service running in the container directly from your host shell or by opening a shell inside the container.

From the Host Shell

Make sure you have sourced the workspace overlay on your host so ROS 2 recognizes your custom packages:

cd ~/Desktop/MCE550/warde
source install/setup.bash
ros2 service list
ros2 service call /spawn_beer spawn_tools/srv/SpawnBeer   "{entity_name: 'beer2', x: 2.0, y: 3.0, z: 0.25}"

From Inside the Container

docker exec -it warde_ws bash
source /ros2_ws/install/setup.bash
ros2 service list
ros2 service call /spawn_box spawn_tools/srv/SpawnBeer   "{entity_name: 'box1', x: 0.0, y: 0.0, z: 0.0}"

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Best Practices

• Keep ROS 2 packages minimal and declare all <depend> tags
• Use --symlink-install for faster dev cycles
• Lock Gazebo/ROS versions in Docker for reproducibility
• Write small, single-purpose Behavior Tree nodes
• Handle service timeouts and failures gracefully
• Version-control all your launch and config files

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Further Reading

• BehaviorTree.CPP Tutorial
• ROS 2 Navigation 2
• Gazebo SDF Documentation

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Enjoy building and wandering with WARDE!