The iMETRO Dynamic Simulation: An Open-Source Simulator for Intravehicular Space Robotics Research

Abstract

We present the iMETRO Dynamic Simulation, the first open-source dynamic simulation environment for research in the use of robot manipulators inside space vehicles for maintenance and logistics tasks, or intravehicular robotics (IVR). IVR has great potential to facilitate science and exploration on the Moon by saving crew time, but there are limited open-source resources that would enable researchers to identify the next set of challenges in manipulation for IVR. We provide a full-featured, high-fidelity dynamic simulation of the real-world iMETRO IVR test facility, which includes mockups representative of the interior of a future space vehicle as well as an 8-DoF manipulator that serves as an example robot platform for this research. Our modular simulator enables new software, hardware, and operational paradigms to be tested in a reconfigurable mockup environment. To improve the accessibility and extensibility of this simulation environment, we also provide ROS 2 hardware control interfaces to MuJoCo as well as a model conversion tool such that the same models may be used with ROS 2 and MuJoCo. To evaluate the sim-to-real transfer capabilities of this simulation, we present an open-source example application demonstration developed in the simulation and transfer it to the real-world iMETRO facility in less than a day. Finally, we identify the challenges and opportunities in modeling a real-world facility to aid future simulation efforts. The open- source simulation and application can be found at https: //github.com/NASA-JSC-Robotics. The MuJoCo and ROS 2 integration tools have migrated to the ros-controls organization and can be found at https://github.com/ ros-controls/mujoco_ros2_control.