A MATLAB/Simulink-Based Sim2Real Control Framework for the Unitree G1 Using ROS 2 and MuJoCo

Abstract

Control research on humanoid robots requires environments where control strategies can be designed, tuned, debugged, validated, and transferred to real hardware with minimal friction. For commercial platforms such as the Unitree G1, this process is often fragmented across separate tools for modeling, simulation, communication, visualization, and deployment, slowing down controller development and experimental iteration. This work presents a MATLAB/Simulink-based Sim2Real framework for the Unitree G1 that integrates MuJoCo and ROS 2 into a unified workflow for control-oriented research. The framework is organized around a modular Variant Subsystem that switches between a MuJoCo simulation backend and a ROS 2 real-robot backend while preserving compatible interfaces, enabling reuse of high-level control logic, monitoring, and system instrumentation across both domains. This is especially valuable for robotics control, where rapid prototyping, closed-loop debugging, structured block based design, and repeatable validation are critical for moving from controller concept to hardware testing. As a representative example, a standard ankle motion command task was validated both in simulation and on the real robot. The proposed framework establishes a practical model-based environment for implementing and evaluating control strategies on the Unitree G1, while providing an extensible basis for future estimation, stabilization, perception, and humanoid control modules.