Multi-robot systems: Controlling a Swarm using Consensus Protocol

Multi-Robot systems course project

Faculty of Electrical Engineering and Computing in Zagreb

2023./2024.

Download Docker simulator

Start Docker Container

In one terminal copy/paste :

sudo  docker  start  -i  mrs_project_2

In other terminal copy/paste

sudo  docker  exec  -it  mrs_project_2  bash

your terminal prompt should change from

<your username>@<your hostname>

to

developer@<your  hostname>

This signals that you are currently "inside" the container.

Clone and build the project

• Clone this project in: ~/catkin_ws/src

git  clone  https://github.com/bornaparo/mrs_project2_simulation.git

• Build: $: ~/catkin_ws/

catkin  build

Modification

Delete everything from /home/developer/catkin_ws/src/sphero_simulation/sphero_stage/launch directory and paste into it everything from /home/developer/catkin_ws/src/mrs_project2_simulation/launch_for_sphero directory

Communication

Who can communicate with whom is defined as adjacency matrix in .txt file where elements in column are delimited by space, size of the matrix is NxN where N is the number of robots in the simulation. Row sends messages to column. For example, adjacency matrix:

0 1 0
0 0 1
1 0 0

Describes that first robot sends messages to the second, second sends messages to the third, and third sends messages to the first. This formation is shown in image below:

Formation

Formation is also defined in .txt file as matrix where columns are delimited by space. Size of the matrix is Nx2 where N is the number of robots in simulation, number of columns is 2 which corresponds to the x and y coordinate of the i-th robot.

For example:

0 0
1 0
0.5 1

Defines that first robots will go to coordinates (0,0), second to (1,0) and third to (0.5,1) and they will form triangle (in this formation). Robots will keep relative distance between each other as defined in formation file, if the matrix in formation file has all zeros, robots will perform rendezvous and they will collide with each other.

Note: number of robots N needs to be the same in adjacency matrix and formation matrix

Launch example

roslaunch mrs_project2_simulation empty_map_square_leader_launch.launch

If the leader exists (defined as parameter in launch file), you can set goal position which formation needs to achieve, for example:

rosservice call /set_goal_position "x: 3.0
y: -3.0"

Videos:

Simple Maze Map Consensus protocol square formation

Consensus-based rendevouz1

Consensus-based rendevouz2

Consensus-based line formation

Consensus-based square formation

Consensus-based triangle formation

Simple maze map consensus protocol triangle formation

Simple maze map consensus protocol line formation