Gazebo Classic is the original, monolithic robot simulator created in 2002 at the University of Southern California (USC) by Andrew Howard and Nathan Koenig, later developed by Willow Garage and the Open Source Robotics Foundation (OSRF / Open Robotics). For almost two decades it was the de facto standard for simulation in the ROS 1 ecosystem — with ready-made worlds, plugins, and robot models (TurtleBot, PR2, Husky, Quadrotor, DARPA Atlas).
Gazebo Classic uses the ODE physics engine (by default), Bullet, Simbody, and DART, OGRE 1.9 rendering, and a client-server architecture with transport based on ZeroMQ and the ignition-transport library. Support for all popular sensors: RGB/depth cameras, IMU, GPS, 2D/3D LiDAR, force-torque. Integration with ROS 1 via the gazebo_ros_pkgs package and with ROS 2 via gazebo_ros2_control (up to and including the Foxy distribution).
In September 2025, OSRF officially ended support for Gazebo 11 Classic — discontinuing the line. All new projects should use Gazebo Harmonic (gz-sim) of the new generation. Gazebo Classic remains in use in tens of thousands of existing academic and educational repositories.
Simulation software is used for modelling, testing, and validating robot behaviours, sensor characteristics, environments, and algorithms without requiring physical hardware. It enables safe, repeatable, and cost-effective development cycles. Common robotics simulators include Gazebo, Isaac Sim (NVIDIA), MuJoCo, PyBullet, and Webots, each offering different trade-offs between physics accuracy, rendering fidelity, and integration with middleware frameworks such as ROS 2.
A Developer Tool is software designed to support the development workflow, including configuration, debugging, testing, monitoring, validation, and integration of robotic and embedded systems. Examples include IDE plugins, visual debuggers, log analysers, hardware-in-the-loop (HIL) test harnesses, and code-generation utilities specific to robotics platforms.
DARPA Robotics Challenge (2013–2015) — simulator for Atlas, Valkyrie, HUBO, and others. Toyota HSR, PAL TIAGo, Willow Garage PR2, Clearpath Husky/Jackal, TurtleBot 2/3. ROS-Industrial Consortium, IEEE Robotics Olympiad.
answers.gazebosim.org with thousands of questions, ROS Discourse > 50k users employing gazebo_ros_pkgs, ROSCon presentations 2013–2024. Main repo github.com/osrf/gazebo ~1.3k★.
Boston Dynamics bipedal humanoid robot. The fully electric generation unveiled in 2024 succeeds the hydraulic Atlas that was retired after more than a decade of research.
Tutor Intelligence industrial robot designed for palletizing, depalletizing and case-picking in warehouses and factories, offered as Robotics-as-a-Service from $14/hr.
Bipedal humanoid robot by Unitree Robotics, designed as a compact research, development, and developer platform.
Unitree H1 is a full-size general-purpose humanoid robot (~180 cm, ~47 kg). Bipedal, 5 DOF per leg + 4 DOF per arm, 3.3 m/s walking speed, 360° perception via 3D LiDAR + depth camera, Unitree M107 PMSM joint motors with ~360 N·m peak knee torque. Standard compute: Intel Core i5/i7; optional NVIDIA Jetson Orin NX.
Ubuntu 20.04 recommended as host. Support ended in September 2025.
License family: Permissive
Official OSRF end of support for Classic; migration to Gazebo Harmonic recommended.
Last significant fixes, preparing for EOL.
Stability update, last release in the 11.x branch focused mostly on fixes.
Final Classic release; Python 3, compatible with ROS Noetic.
Last LTS before Gazebo 11; supported until January 2023 alongside ROS Melodic.
