The National Research Council has released a report, commissioned by NASA and the US Air Force, on 3D Printing in Space.
Although fairly positive about the long-term value of 3D printing in space, the study throws some cold water on its near-term prospects.
“Many of the claims made in the popular press about this technology have been exaggerated,” said Maj. Gen. Robert Latiff (USAF-ret.), chairman of the committee that wrote the report.
The report says that 3D printing could contribute to space missions by enabling on-orbit manufacturing of replacement parts and reducing logistics, but the specific benefits and scope of the technology’s use remain undetermined.
“For in-space use, the technology may provide new capabilities, but it will serve as one more tool in the toolbox, not a magic solution to tough space operations and manufacturing problems,” Latiff said. “However, right now NASA and the Air Force have a tremendous resource in the form of the International Space Station. Perfecting this technology in space will require human interaction, and the Space Station already provides the infrastructure and the skilled personnel who can enable that to happen.”
Of course, no one ever claimed that 3D printing was a magic solution to every space operations and manufacturing problem. General Latiff is fighting a strawman.
The committee’s analysis is limited by assumptions that tie 3D printing to the International Space Station, rather than the new commercial space architecture which is likely to emerge in the near future. Unfortunately, ISS may be more of a millstone than a “tremendous resource” Latiff believes.
The committee says that “a number of… obstacles need to be considered in the cost-benefit equation for [3D printing]…. Automation presents an unknown cost, because while it is often cheaper and more efficient to have human labor complete basic tasks, such as moving parts from one machine to the next, human labor in space is very expensive. At a minimum, further investments in human telepresence and robotics will be required.”
It’s not surprising that the committee considers human labor in space to be prohibitively expensive, given the study’s emphasis on the International Space Station.
The report acknowledges that several other free-flying platforms will likely be available within the next decade, including the SpaceX DragonLab, Orbital Science Cygnus, and Bigelow Aerospace space stations (which the report refers to as “structures,” rather than “stations”). The report says that these platforms could serve as “points of entry” or test beds for 3D printing but “have limitations that would preclude them being used for a permanent manufacturing facility.”
“While these vehicles have dynamic control systems, communications, and telemetry capability,” the report says, “The available volume is a concern. Their internal volumes are quite small. The size of a manufacturing facility in orbit is dependent on the scale of the products for manufacture. Whether a small vehicle free flyer or a Skylab-sized orbiting facility is necessary will be driven by satellite requirements. In addition, power needs will be a major factor, as will the level of automation needed to conduct the manufacturing process.”
Yet, there’s no reason why a Bigelow space station couldn’t be as large as Skylab or ISS (or even larger). Nor is there any reason why Bigelow couldn’t add additional solar arrays, if more power is required.
Rather than considering such solutions, the report assumes that ISS (which it refers to as the space station) will be a more useful platform.
“It might be possible to design free-flying experiments that could operate out of the space station,” the report says, “but that will add complexity to the ISS missions. In any event, the design, construction, and operation of any free-flyer platform for the support of an established manufacturing capability on orbit is a major undertaking.”
The annual operating costs of ISS exceed the expected development and deployment costs of a Bigelow space station, however. To put it another way, Bigelow could put up a new space station every year for less than what NASA spends to maintain ISS. As the late G. Harry Stine said, in a similar context, “An elephant is a mouse built to government specifications.”
A Bigelow space station may be a major undertaking by commercial space standards, but it would be a modest expenditure compared to what the US has spent on ISS (or what industry spends on major construction projects on Earth, such as large offshore oil platforms).
The report also fails to consider the development of new space transportation systems, which could radically reduce the cost of access to space. The report mentions the Sierra Nevada Dream Chaser and Boeing’s X-37B space plane, but there is no mention of fully reusable vehicles or any means of access to space other than expendable rockets.
Systems like the SpaceX Dragon, Sierra Nevada Dream Chaser, and Boeing X-37B are not the end of space-vehicle evolution, however. The Dragon capsule and Dream Chaser lifting body are designed to serve NASA’s (very limited) requirements for servicing the International Space Station. With a very low flight rate and large government budget, NASA does not see a need for reusable vehicles with low cost and high operability. As a result, NASA’s COTS and CCDev programs have fallen back on very conservative designs, using expendable launchers.
Commercial and military requirements will drive much higher flight rates. In the business world, transportation delays cost money. In the military world, delays cost lives. Whether you’re managing commercial logistics or trying to win a war, the strategy is the same: to “get there firstest with the mostest.” Whether the goal is to open the space frontier to commercial enterprise or ensure military superiority over that frontier, a new type of space-transportation system is needed: one that is capable of reliable, low-cost, fast-tempo operations.
Industry has been working on the development of such systems. Companies such as Blue Origin, Masten Space Systems, Virgin Galactic, and XCOR Aerospace, have been developing fully reusable suborbital spacecraft — the first step toward space. SpaceX has begun work to evolve its Falcon 9 expendable launcher into a partly reusable orbital system. And recently, the Defense Department has thrown its hat into the ring when DARPA announced three Phase 1 contracts for an Experimental Spaceplane capable of flying to Mach 10, launching a satellite into orbit, returning to the launch site.
The NRC report is right, in one respect. The future of 3D printing in space is exaggerated, if you look at it in isolation from other developments. Given the cost of existing space launch and operations, the market for and utility of 3D printing (and most other space applications) is quite limited. But frequent, cheap access to space will change the cost equation for 3D printing and space development in general.