Moonshots

Printing Our Future

Rob Bell

Issue 14, August 2018

Will 3D printing become the standard of construction in the future?

There’s a huge inefficiency in construction today. With so many materials, there’s mining at one point, refinement in the next place, manufacturing in another, then construction onsite. Can in-situ fabrication provide the best economy, using materials available at the destination?

This isn’t an idea that is locked to Earth either. It can provide some huge efficiencies in construction if we’re to colonise Mars, or any other future adventure beyond our own planet.

INTERSTELLAR CONSTRUCTION

One of the massive challenges we have doing anything in Space is the massive amounts of energy it takes to launch objects to overcome the gravitational pull of Earth, and beyond. Of course, in space, the lack of persistent gravity changes the engineering approach to large objects that are going to stay in space. Indeed, for those destined for another planet will have to cater for the new planet’s gravity and perhaps atmospheric conditions.

Of course we can also create lattices and complex shapes which are structurally strong, but difficult to manufacture using traditional methods. At a hobby level, we think of plastics. However, printing with concrete, metals, and importantly - chocolate - are all possible and in use already.

Even using geo-dome style concept design, the tube-frames could potentially be printed from more space-efficient raw materials to save on space during transport.

OBJECT PRINTING

One circumstance we may encounter, is when a required base material isn’t available, or is too difficult to source or manufacture at the destination. If this is the case, sending the raw material with the ability to manufacture with it, is likely to be more efficient than a finished product.

One thing we don’t want to be transporting into space is space. By that, I mean large objects with little mass. Hollow tubes and such, which could make an easy frame, are horribly inefficient in terms of storage - due to all that unused space! It’s the same reason that even on Earth, couriers have a “cubic weight” component of their cost calculations for large but lightweight packages. They take up lots of room in the truck!

So, instead of creating objects in the shape we want them and shipping them to the job site (or planet), we simply send the raw materials to later be fabricated into whatever we need.

USING AVAILABLE MATERIALS

When we think about going to Mars, the Moon, or anywhere else, we often think about what we’ll need to take. Food, water, oxygen, perhaps some entertainment... But what about when we arrive? Or even our AI-driven advance-team which preceed our arrival by months, years, even centuries?

Even though there’s no breathable atmosphere on Mars, there’s loads of water stored as ice, and dirt. Oh my is there DIRT! Rusty, iron-laden dust (the cause of the reddish colouring) for miles! Perhaps it could be made into a crude form of mud-brick, and molten ice-caps to help slurry the combination together. That puts millions of tonnes of building materials already on-location on Mars - it’s one less thing we have to take with us.

Likewise, our Moon (a much closer target if we wanted to undertake some testing) has ultra-fine dust particles that could be compacted or bound together in some way.

CLOSER TO HOME

It’s important to consider however, that we can find ways to implement these valuable energy and time-saving methods in our own construction.

Just look at what Australian Fastbrick Robotics is doing with their robotic bricklayer. While it’s using robotics in a similar way to manual labour, laying delivered masonry bricks to create an entire house in just a few days. 3D printed houses are already being lived in around the world, and these experiments will ultimately yield some winners.

If these machines can be trained to adapt to a variety of different input media (or even bind different aggregates together with a standardised binder), we can reduce or eliminate the need to send anything but the machinery required for construction, and use the planet or Moon’s own resources on-site to create a habitable city ahead of our arrival!

THE TIMELINE

While we might not quite be there yet, many of the major hurdles we have are related to keeping ourselves alive. Sure, we don’t have automated house-building machines just yet either, but that’s probably not far off. Once we don’t need a human to run the machine, starting interplanetary construction becomes a much more viable reality.

After all, we’ve been sending unmanned machines to space for decades! Without the risk to human life, the only consequence of failure is a financial one.