04-06-2019 | | By Christian Cawley
The space race is no longer the province of nations or pan-continental unions. In the 21st century, corporations are investing in the vehicles and infrastructure needed to profit from alien resources and zero gravity manufacturing.
New materials and techniques are already being tested and developed thanks to on-orbit manufacturing.
Manufacturing beyond the environmental restrictions of our home planet isn’t as far fetched as it may seem. For decades experiments have been conducted into how heat, atmosphere, and gravity affect manufacturing.
In the age of the International Space Station, such experiments are now developing into small scale on-orbit manufacturing excursions, but many of the materials now being researched were first developed on-board the space shuttle or on parabolic flights through the upper atmosphere.
These materials, many of which could improve technology and human lifespan, include ZBLAN fibre optics, synthetic human organs, and the Liquidmetal alloy.
Space manufacturing in space requires a material that is worth money, in high demand, and light enough to transport. ZBLAN, a fibre optic originally developed on Earth, might be just the product to kickstart off-Earth manufacturing.
When manufactured on the surface, ZBLAN has a crystallised, tree-bark structured. This limits how fast data can be sent. But when created in microgravity, the crystals are less likely to occur.
Even better, the manufacturing process for ZBLAN is surprisingly compact. In December 2018, space manufacturing company Made In Space dispatched a microwave-sized machine to the International Space Station which was able to output 100 meters of ZBLAN fibre optic cable.
Organ replacement technology could prolong human life by decades but creating synthetic body parts has proved challenging. Although it is possible to build cellular structures using a rotating vessel on Earth, as soon as a cell meets a restrictive surface (such as a container wall), it stops growing as instructed.
Is off-Earth manufacturing the answer?
In space, cells can form larger tissues, and NASA is enthused by the technology enough to launch an initiative, the Vascular Tissue Challenge. To win the $500,000 prize, researchers must successfully grow vascularised (that is, with a blood supply) heart, lung, kidney, liver, and muscle tissues to over 1cm thick. Tissues must survive for 30 days, which is currently impossible with Earth-manufactured tissue.
With qualities like plastic yet stronger than titanium, Liquidmetal is an alloy developed using the microgravity conditions on the space shuttle, with experiments conducted during two microgravity flights in 1994 and 1997.
Leading research into Liquidmetal, Dr. Bill Johnson of Caltech has even used electrostatic levitation to further research, also creating a second alloy, Vitreloy. Possessing strength, elasticity, and the ability to handle stress without losing shape, Liquidmetal has a range of uses, from ruggedization of tech hardware to sports equipment and even military applications.
Success for these materials can only lead to more research and an increase in space manufacturing. The next step would seem to be space stations dedicated to manufacturing materials for processing on Earth, until such a time when it becomes feasible to manufacture and process on a single installation.
As the price of space travel decreases, this future is looking increasingly likely.