The Interplay Between Space and Sea Technologies
6th Sep 2024Whether it’s the psychological effects of isolation, the physical demands of undertaking assignments in extreme conditions, or the mental challenge of navigating complex engineering obstacles, there are striking similarities between working at sea and in space. Here, we take a closer look at how these mutual experiences have led to shared technologies – and associated optical components – that bridge the gap between the deep blue and the great beyond.
From NASA and the ESA (European Space Agency) to the JAXA (Japan Aerospace Exploration Agency) and the CSA (Canadian Space Agency), agencies around the globe harness the parallels between the sea and space, and it all starts with training their astronauts. This development usually takes place in precision-designed venues, some of which are large enough to hold up to nine Olympic-sized swimming pools[1]. Two renowned examples are NASA’s Neutral Buoyancy Laboratory (NBL) and ESA’s Neutral Buoyancy Facility. As the names suggest, the neutral buoyancy within the complexes allows astronauts to simulate the closest possible experience to the microgravity domain of space – whether for Extravehicular Activities (EVAs) or teamwork exercises.
Cross-Disciplinary Tech
Alongside NASA’s and ESA’s facilities, other submersed training centres worldwide make use of leading instruments that overlap subsea and space fields. Whether it’s dedicated robotics, high-resolution imaging, or cutting-edge communication setups, these efforts enhance astronaut education and subsea initiatives, improving overall outcomes of task simulations and pre-mission preparation.
Let’s explore how a handful of these technologies typically integrate to bring together innovations across the two sectors:
Robotics
Intrinsically linked with organisations like NASA – which is deeply involved in both space and deep-sea discovery – the lines between submersible and spaceborne robotics are regularly blurred. They’re instrumental in reducing the dangers of operating in these adverse terrains for humans. As a case in point, in space, rovers, orbiters, and landers serve as safer alternatives throughout missions. Similarly, beneath the water’s surface, subsea robotics, such as remotely operated vehicles (ROVs), unmanned underwater vehicles (UUVs), and autonomous underwater vehicles (AUVs), operate in unfavourable conditions, venturing deeper than human divers can.
One illustration is Nauticus Robotics’ Aquanaut. Produced with expertise from NASA’s space robotics[2], this bot is a prime example of interdisciplinary skills converging. The robot operates autonomously under the water, performing jobs like inspections and servicing, thanks to sophisticated optics-integrated vision systems, robotic arms, and sensors – all primarily destined for space missions.
Another instance can be seen in the reassignment of the robotics that were once employed for skill building in centres like the ones we highlighted earlier. In 2015, the Eurobot Wet Model, initially developed by the ESA for teaching their astronauts, was repurposed to examine just how robotics for space preparation could be adapted for subaquatic duties like inspecting structures or conducting archaeological research[3].
Although there is some crossover between both markets and positions, the benefits of these astronaut-training submerged robots are evident, and they’re still deployed in testing locations today. At ESA’s Neutral Buoyancy Facility, a specially built robotic arm helps astronauts by simulating real-life space settings as accurately as possible. This assists the user with movement and positioning while carrying out tasks like hardware installation and maintenance, closely replicating what space explorers will actually encounter in genuine EVAs[4].
Watch the video here.
Optical Components for Subsea and Space Robotics
Optics are important for optimising the functionality of robots used in space, subsea, and cross-industry applications. The progress we’ve achieved in the 21st century – notably surrounding imaging, sensing, navigation, control, and data collection – are largely due to top-performing optical systems.
Each optic, from Lenses and Windows to Filters, plays a critical role, and every specification, including wavelength compatibility, application-specific coatings, and – especially for subsea and space industries – substrate durability must be carefully considered.
To make sure your optics fulfil the unique criteria of your application, we recommend partnering with an optical specialist early in the design process to help guarantee your components are tailored to your exact specifications, ensuring seamless integration with your robotic projects.
Underwater Imaging Systems
To successfully analyse underwater training scenarios and translate abilities to real-life space predicaments, high-definition imaging systems are brought in to provide in-depth assessments. The advanced configurations not only facilitate accurate evaluation of simulation drills but also showcase the progressive steps that the space sector has taken to the rest of the world. By recording high-quality images and videos, the systems play a key part in logging and sharing milestones with the public, inspiring the next generation of astronauts and highlighting technological advancements in space and, in this case, subsea investigation and evolution.
The NASA Extreme Environment Mission Operations (NEEMO) scheme is a notable example, where aquanauts and scientists are stationed in the Aquarius underwater research premises for up to three weeks[5]. Like NASA’s NBL and ESA’s Neutral Buoyancy Facility, Aquarius simulates the conditions of space missions to support training. In these space-like environments, sharp underwater visuals are key to documenting things like crew operations. The photos and videos captured by the systems are indispensable for assessing efficiencies and verifying the capabilities of systems intended for launch, bringing us to our upcoming point, system checks.
These imaging techniques are also pivotal in capturing detailed information during equipment tests, such as those for the ESA’s lunar rescue device, a pyramid structure fabricated for astronauts to rescue any out-of-action crewmates in lunar gravity. By using state-of-the-art cameras, the ESA was able to get a clear view of how the device performs underwater, which helped in analysing and fine-tuning it for final stage deployment[6].
Optical Components for Underwater Imaging
Briefly looping back to robotics, innovative imaging systems are frequently integrated into autonomous underwater vehicles such as ROVs, UUVs, and AUVs, allowing the system to capture shots from difficult-to-access spots and spaces that pose limitations for human divers. To enable full capabilities and protect internal components, devices are often shielded from the high-pressure underwater environment of the deep sea by a durable Optical Dome.
These Domes are a popular choice for such uses due to their adequate protection of imaging systems. This is due to their natural shape, which provides an optimal protective viewport for submersibles. Depending on the distinct requirements, including application, scale, and budget, Optical Domes are commonly specified in materials such as BK7 (or equivalent), Sapphire, or Acrylic, each selected to meet the necessities of exceptional imaging in underwater environments.
LiDAR (Light Detection and Ranging)
Shifting our focus ever so slightly from the ocean to the vast expanse of space, many spaceborne tech offers crucial observations into marine life and climate issues, such as polar ice melt data and coral reef degradation awareness. Floating above our heads as you read this, there are approximately 9000 active satellites in orbit[7]. In 2021, scientists used one of them, the ICESat-2, and its LiDAR data to assess the exact impact of sea level rise. By mapping land areas less than 2m above sea level, they could identify regions particularly vulnerable to the impacts of rising sea levels[8], giving us even greater insights into what’s happening here on Earth from up above.
Optical Components for Spaceborne LiDAR
A wide range of metrology-tested optics – including Beamsplitters, Collimators, Diffusers, Mirrors, Prisms, and Infrared (IR) Lenses – are essential for enhancing the effectiveness of today’s pioneering LiDAR systems. For spaceborne LiDAR, in particular, additional factors must be considered when specifying optics for peak efficiency. The extreme temperatures and radiation circumstances satellites are subjected to in space can significantly affect optical performance, and to address these challenges, specialised coatings and custom-made optical components are often required to ensure reliable operation.
For more details on custom-made optics, coatings, and optical components specifically designed for subsea and space applications, or to discuss your current project, please contact a member of the Knight Optical team.
FOOTNOTES:
[1] https://www.nasa.gov/podcasts/curious-universe/the-astronaut-training-pool/
[2] https://spinoff.nasa.gov/Space-Robotics-Take-a-Deep-Dive
[3] https://phys.org/news/2015-10-exploring-seas-space.html#google_vignette
[4] https://www.esa.int/ESA_Multimedia/Videos/2021/03/Underwater_spacewalk_training_with_Thomas_Pesquet#
[5] https://www.nasa.gov/mission/neemo/
[6] https://www.esa.int/ESA_Multimedia/Images/2019/06/Testing_LESA_at_NEEMO_23