ws24-multi-robot-task-distribution

Multi-Robot Task Distributions

Description

The project aims to migrate a multi-robot task distribution system, originally developed using ROS1 to ROS2. The system simulates robots working collaboratively in a warehouse to fetch items based on client requests. The migration ensures compatibility with ROS2’s improved communication features and long-term support. ROS2 provides enhanced multi-robot communication, security, and real-time control features. Thus, migration is required to ensure system sustainability and to benefit from ROS2’s advanced tools.

Features

1. The system will be able to run and simulate in ROS2, provinding a stable environment for multi-robot communication.

Scope

Tools/Software Used

1. Ubuntu 20.04
2. ROS Humble
3. Python
4. Git
5. DDS

Installation and Project setup.

You need ROS Humble version to use these packages.

• Please install ros humble using this link and instructions https://wiki.ros.org/noetic/Installation

Running Simulation

Prerequisites

Make sure you have the following installed on your system:

• ROS (Robot Operating System) - Installation Guide
• Git

1. Create a ROS Workspace

First, create a new ROS workspace and initialize it:

mkdir -p ~/ros_ws/src
cd ~/ros_ws/
colcon build

source install/setup.bash

Clone the Package Navigate to the src directory of your workspace and clone the repository:

cd ~/ros_ws/src
git clone [email protected]:HBRS-SDP/ss24-multi-robot-task-distribution.git

Build the Package After cloning the repository, go back to the root of your workspace and build it using

colcon build

Run the Nodes

You can now run the nodes provided by your package. Open a new terminal, source the workspace, and use rosrun or roslaunch to start your nodes:

# Source the workspace
source ~/ros_ws/install/setup.bash

# Launch the launchfiles

SM_Module

Shared Memory Module logs he robot activities and manages the Inventory. It integrates with ROS to handle real-time updates and communicate with robots.

Task Distribution Overview

Multi-Robot Task Distribution in ROS2

In our ROS2 migration, we replace the ZeroMQ-based broker with a ROS2-native solution DDS for distributing tasks among robots. The architecture consists of a Broker Node that assigns tasks to Worker Nodes (robots) based on availability and load balancing.

Architecture Overview

1. Broker Node:

   • Listens for task requests from Client Nodes via ROS2 services or actions.
   • Maintains a registry of Worker Nodes and their statuses (idle, busy, etc.).
   • Distributes tasks to available workers based on a custom load-balancing strategy.

2. Worker Nodes:

   • Publish their availability on a status topic (e.g., /worker_status).
   • Receive and execute tasks assigned by the Broker.
   • Update the Broker on task progress and completion using actions or services.

3. Client Nodes:

   • Send task requests to the Broker, which then routes them to appropriate Worker Nodes.

Implementation Notes

• ROS2 Services and Actions enable reliable task assignment and feedback.
• Quality of Service (QoS) settings ensure robust communication, even with varying network conditions.
• DDS Discovery allows dynamic scaling, enabling new Worker Nodes to register with the Broker automatically.

This ROS2 setup leverages DDS for fault tolerance, scalability, and efficient intra-process communication, making it ideal for multi-robot task distribution.