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arXiv · 2609.08010

mjorbit: A Simulation Framework for Space Robotics

John Z. Zhang·Joris Verhagen·Fausto Vega·Patrick McKeen·Zachary Manchester
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Abstract

This paper presents a general framework for simulating multi-body space robots with contact. We bring efficient, large-scale robot simulation to in-space servicing, assembly, and manufacturing applications. First, we perform an empirical trade study of methods for coupling orbit propagation with existing robotics simulation frameworks. Next, we present mjorbit, a general, flexible, and performant framework built on the MuJoCo engine widely used in robotics, to which we add key spacecraft dynamics, actuators, and sensors. We provide a low-latency C++ CPU backend and a high-throughput GPU backend behind a simple Python API. We demonstrate mjorbit by solving several realistic on-orbit case studies with both model-predictive control and reinforcement learning. Open-source code and examples are available at: https://johnzhang3.github.io/mjorbit/

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John Z. Zhang, Joris Verhagen, Fausto Vega, Patrick McKeen, Zachary Manchester. 2026-09-07. mjorbit: A Simulation Framework for Space Robotics. https://arxiv.org/abs/2609.08010

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