Characterizing the Visual Experience of Astronauts at the South Pole – NASA

Humans are returning to the moon — this time, to stay. Because our presence will be more permanent, NASA has chosen a location that maximizes visible interactions with Earth, solar visibility, and access to water ice: the Lunar South Pole (LSP). . While the Sun is more consistently at the poles in the lunar sky, it never rises more than a few degrees above the horizon. In target landing areas, the maximum possible elevation is 7°. It offers a harsh light environment never experienced during the Apollo missions, or indeed, in any human spaceflight experience. Ambient light will adversely affect the ability of personnel to see hazards and perform simple tasks. This is because the human visual system, despite having a high dynamic range, cannot see well in bright light and cannot quickly adapt from light to dark or vice versa. Functional vision is required to perform tasks ranging from simple tasks (eg, walking, operating simple tools) through operating complex machines (eg, lander lifts, rovers). As such, the environment presents an engineering challenge to the agency: one that must be broadly understood before it can be effectively addressed.

In past NASA missions and programs, extravacuolar activity (EVA) or rover operations for lighting design and functional vision support systems have been managed at the lowest program level. This worked well for Apollo and low Earth orbit because the angle to the Sun was managed by mission planning and astronaut self-positioning. The design of the helmet itself solved all the vision challenges. The Artemis mission presents new challenges for active vision, as astronauts will not be able to avoid having the sun in their eyes most of the time on the lunar surface. This, combined with the need for artificial lighting in the extensive shading at LSP, means that new functional vision support systems must be developed into all projects and programs. The design of helmets, windows, and lighting systems should work in a complementary manner, within and across programs, to achieve a system of lighting and vision aids that enable the crew to see in the dark. While their eyes are light-adapted, in bright light. Still adapted to darkness, and protects their eyes from injury.

Many of the evaluation findings focused on the lack of specific requirements to prevent functional vision impairment due to sunlight (which is different from preventing eye injury), while keeping astronauts well enough to perform specific tasks. They were able to see. In particular, the tasks expected of astronauts in the LSP were not included in the system design requirements to enable the development of systems that ensure functional vision in predictable lighting environments. Consequently, spacesuits, for example, have flexibility requirements to allow astronauts to walk but not to ensure that they can see well enough to walk from bright sun into deep shadow and back. can and without the risk of tripping or falling. Importantly, gaps in the distribution of requirements across programs were identified to ensure that the role of the various programs was for everyone to understand the functional vision. NESC recommendations were introduced that made enabling active vision in harsh lighting environments a specific and new requirement for system designers. Recommendations also include coordinating lighting, window and visor designs.

The evaluation team recommended that a variety of simulation techniques, physical and virtual, need to be developed, each with different and well-defined capabilities with respect to functional vision. Some will address the blinding effects of sunlight on LSP (not easily captured by a virtual approach) to evaluate the performance of helmet shields and artificial lighting in the context of the environment and adaptation times. Can be. Other simulations will incorporate terrain features to identify hazards (e.g., walking, sample collection) and complex (e.g., equipment maintenance and operation). As different facilities have different strengths, they also have different weaknesses. These strengths and limitations should be characterized to enable verification of technical solutions and staff training.