The National Renewable Energy Laboratory (NREL) is working with NASA and Lockheed Martin to provide a way to ensure that the Orion command module will remain upright between splash down and recovery.

NASA is gearing up for a return to the Moon with the launch of the Artemis I mission scheduled for 2021 where an uncrewed lunar test flight will happen. It will be the first flight of the new Space Launch System, a heavy-lift launch vehicle. Later, the Orion crew module will orbit the moon for multiple days before returning to Earth and landing in the Pacific Ocean.

NREL is using a wave energy converter simulator (WEC-Sim) to ensure that the command module uprights upon landing. When the command module is inverted or even sideways, hatch doors and the antenna can become submerged as well as impede recovery operations. Many Apollo missions suffered this outcome with the command module becoming inverted after splash down.

NASA plans to use a system called the Orion Crew Module Uprighting System (CMUS), which consists of five airbags intended to right the command module if it becomes inverted in an ocean landing.

The WEC-Sim tool models the forces of a floating object and calculates its behavior allowing NREL researchers to convert the motion of waves into usable energy. An improved understanding of how this works can help replace some of the would-be physical testing with computer modeling.

Unlike the Apollo uprighting system that came with previous moon missions, the CMUS will be subjected to a small number of tests instead of relying more heavily on modeling.

"WEC-Sim caught our attention as a viable option for modeling the dynamics of the CM in the open ocean since its size is similar to that of the wave energy converters that WEC-Sim was designed to simulate," said Tannen VanZwieten of the NASA Engineering and Safety Center. "Both require a fairly high-fidelity model of the interaction with the wave field to capture the motion of the system."

Essentially, WEC-Sim is helping NASA and Lockheed Martin to credibly model forces and the motion of the CM in the ocean.

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