Multi Hetero Agent Exploration by Unitree GOs

Author: Sayantani Bhattacharya

Project Overview

In times of disaster, every second counts, and reaching survivors in hazardous terrains poses significant challenges. Imagine a coordinated team of agile, four-legged robots, working together to navigate treacherous environments like dense forests or mines. These quadrupedal robots autonomously perform simultaneous localization and mapping (SLAM), creating real-time detailed maps of their surroundings. By employing decentralized collaborative system, these robots can share and merge their individual maps, creating a comprehensive understanding of the complete area without relying on a central system. This approach enhances the robustness and speed of search operations, as the failure of a single unit does not compromise the entire mission. Quadrupeds inherently work well in uneven terrains, and harnessing the strengths of SLAM to explore unmapped areas with LIDAR and Visual-Inertial sensor data, these robotic swarms represent a leap forward in disaster response, offering hope and assistance when it’s needed most. By all means this is just the first iteration and needs good work for being deployable onsite. </br> For more details about the project plese refer my Portfolio Post

Block diagram

1. Complete system:</br>

1. System Architecture of GO2:</br>

   

2. System Architecture of GO1:</br>

   

Tools and References:

Hardware:

• Unitree GO1 & GO2.
• Zed 2i Camera & On-board 4D Lidar.
• Jetson Orin Nano.
• buck-convertor (24V->12V).
• 3D print the mount for unitree.
• Display port adapters for Jetson.
• Ethernet cable for initial testing with unitree sdk.
• Micro SD cards.

Software :

• C++
• ROS2 Jazzy and Humble
• Python
• Unitree SDK - GO1 and GO2
• Zed SDK
• Slam, RTabMap, and Nav2 pkg

<!– ### Reference repositories:

• Unitree Package abstracted layer developed by Nick Morales, Marno Nel, and Katie Hughes: https://github.com/ngmor/unitree_nav
• Unitree ros2 wrapper: https://github.com/katie-hughes/unitree_ros2
• Visual slam route: https://github.com/GogiPuttar/Search-and-Rescue_Robot_Dog_Unitree_Go1
• Graph based slam route: https://roy2909.github.io/Exploration/

Reference papers for collaborative exploration:

• Awesome paper: https://arxiv.org/pdf/2108.08325

  Has a lot of references, inside: see the annotations.

• Paper of 12 drone c-slam, with github code: http://arxiv.org/pdf/2108.05756
• C-SLAM subproblems such as map merging (Lee et al., 2012), practical implementations (Kshirsagar et al., 2018), particle filter techniques.
• ICRA 2023: generalized back-end for c-slam https://www.youtube.com/watch?v=oypURkSuMc4

ROS2-SDK setup for Unitree GO1

ROS2 was set up by cloning and following the instructions for this repository.

ROS2 Packages

go1_description

Holds all the models for visualizing the Unitree Go1 in RViz and simulation in Gazebo.

go2_description

Holds all the models for visualizing the Unitree Go2 in RViz and simulation in Gazebo.

ros2_unitree_legged_msgs

Messages and services for controlling Unitree Go1.

unitree_exploration

Frontier Exploration with the Unitree Go1. Takes in the map, finds frontiers and commands 2-D goal poses to the Nav Stack accordingly.

unitree_kinematics

Library for kinematic calculations for controlling the Go1.

unitree_nav

Package for code and launch files for running the Unitree Go1 in high level mode with ROS 2 Humble.

unitree_legged_real

Holds the launch files for Zed 2i camera nodes, controlling, visualisation and exploration of Unitree Go1.