As we further consider spacesuits we may find a question arising in many of our minds: Why build any new spacesuits at all? Why not just reuse previous designs, especially when the expense of space technology manufacture is considered?
The answer is that with man’s space exploration program being in many ways still in its infancy and the total number of future mission destinations potentially limitless, so in equal measure are the number of spacesuit designs that may be required. One reason of course for this is that although the micro-G environment in which many Space Age EVAs have been performed would rarely require a new suit design for operating within it again in the future, the comparatively different partial gravity environments such as on the planets, would. Ultimately exploring new terrain and atmospheric conditions in space demands new suit specifications, as was the case with Earth-orbit EVA’s compared to the Moonwalks.
Moreover, where the prize for improved design elements may be for the mission as a whole to yield only greater results, coupled with the fact that even the most complex and carefully made spacesuits of previous years eventually show signs of wear and tear, the manufacture of spacesuits will continue to be of critical importance for a long time yet. However where major improvements are the objective and with only a handful of mission-successful-spacesuits ever to provide concrete points of reference, each new design has the onerous responsibility of effectively being a prototype. Added to the knowledge that even the best test simulation environments on Earth often pale to the unforgiving and somewhat unpredictable harshness of the real one located a long and very expensive trip away, the manufacture of spacesuits is likely to always be a stimulating engineering challenge. So what spacesuits, if any, are next? Two of the main spacesuits in use today on the International Space Station are of course the American-designed Extra-Vehicular Mobility Unit and the Russian-designed Orlan, both used for spacewalks.
However since the most recent spacesuit configuration’s debut in space (the digitally computerised Orlan MK), in 2009, the suit’s manufacturers NPP Zvezda seem to have another project in motion. Plans appear to be underway for a new Orlan spacesuit called the MKS which could be available for use on the ISS as early as 2015. After many years of service, the Orlan’s outer layer which has been internally lined with rubber is at last to be replaced with Polyurethane. As a synthetic durable material that ‘heals’ itself if damaged a double layer is thought will enhance the occupant’s manoeuvring capabilities and extend the service lifespan of each new spacesuit to a total 20 EVAs. Moreover generations after its development, Sergei Pozdnyakov general director of NPP Zvezda believes a spacesuit based on the Orlan, a descendant of the previously lunar-designed Krechet spacesuit, will some day be adapted for future lunar extra-vehicular activities and so historically herald the first cosmonaut spacewalk. However what about the efforts of the Americans in regards to spacesuit progression? With Extra-Vehicular Mobility Units already serving astronauts effectively as mini-spacecraft, we may wonder what, design –wise is left to improve.
One major challenge NASA has taken on is the kitting-up procedure. Contrary to the Big Screen myth, ‘doffing’ and ‘donning’ spacesuits are not procedures that can be executed at the last minute. The 60-minute requirement of “Pre-breathing” pure oxygen to remove nitrogen dissolved in body fluids and for the body’s gradual acclimatisation to the different air pressures both before and after entering the vacuum of space has, for a long time, been a cumbersome, albeit essential aspect of space missions. Currently under production as a solution to this problem is the Z-1. Rather like hanging your favourite wardrobe outfits outside the windows of your house for all to see, this radical new NASA spacesuit will forever change the look of spaceships, space, and extra-vehicular activities. A type of rear-entry spacesuit, its official title is the ‘Z-1 Prototype Spacesuit and Portable Life Support System (PLSS)’ 2.0. Incorporating a long-employed spacesuit entry-method used in the one-piece Russian EVA Orlans on the ISS, the life-support pack on the astronaut’s back becomes the access hatch for entering this single-section suit.
However the prototype’s access hatch is only the tip of the iceberg. The suit’s backpack door also becomes the ‘suitport’ and will have the facility to ‘lock on’ to a rover, spacecraft, or habitat with its hatch. Just like a service module docking with the ISS, once docked the astronaut can do his/her “Houdini” and disappear from the spacesuit into the spaceship behind it. So the real breakthrough is in that where the air pressure is only 4.3 pounds of force per square inch inside the ‘balloon’ of an astronaut’s EMU, the Z-1’s 8.3psi, much closer to the air pressure inside the spacecraft, should abolish the ‘Pre-breathing’ procedure for crew leaving or returning to the ship. This guaranteed, the suit will have to match the pressure on board before the hatch will unlock and allow the EVA astronaut out. However not only will this engineering feat greatly expand the time-window available to the mission crew for exploring, studying, and working in their specific environment every day they are in space, but the Z-1 suitport approach will completely revolutionise lunar/planetary excursion and solve a problem that hampered all of the J-Missions of the Apollo Program.
Although not referring to some alien virus of the SF genre, the Moonwalk astronauts of the American Apollo missions complained about their lunar-soiled EVA spacesuits ‘contaminating’ the airlock section of the Lander Module when they came back into the carefully controlled atmosphere of the spacecraft. With the Moonwalkers’ coughing, mentioning a slight “gun-powder”-like smell on-board, and feeling some slight facial irritation, in a low-gravity soon to become zero-G flight compartment in space, the presence and potential circulation of notoriously-abrasive lunar dust throughout the cabin’s ventilation system was not an attractive prospect. Therefore as the Z-1 EVA spacesuits will, on future missions always remain on the outside of the spacecraft or rover, the potential for any celestial body surface contamination of the delicate instruments, equipment, and cabin respiratory systems on-board will also be diminished. The final Z-1 spacesuit configuration should be ready for service in 2015.
But finally to answer that big question we all have concerning Z-1: Was it designed with Buzz Lightyear’s spacesuit consciously in mind? Well to date there have been no official comments from NASA to quell the many whisperings about the prototype’s uncanny life-size resemblance to the space fashions of the celebrated PIXAR personality. However presuming that NASA’s complete innocence of said green-motifed spacesuit in contemporary CGI pop culture is the more unlikely of the two possible scenarios, it would seem that in NASA there must be at least one individual who is hoping that this next-generation spacesuit’s deep space exploits will see it go to infinity and beyond. However before we move on, might this final piece of evidence be a case clincher?
Very positively however, it appears that the job of creating new spacesuit technology for potential future deep space and planetary excursions is not simply being left to the same minds and hands that have built much of the space program gear for the last 50 years. Others are up and looking lively, more precisely Professor Dava Newman, Jeff Hoffman, and engineering students from the Massachusetts Institute of Technology along with design firm Trotti and Associates. Seeking to readdress the old-as-the-hills conundrum of safely facilitating a human’s freedom of motion while in the vacuum of space, these engineers are attempting to tackle the problem from an entirely new perspective. Having gone back to the foundational science drawing board of human-space concepts they have taken a different fork in the engineering road already. Rejecting the generally accepted NASA precept that a human being’s survival and operating ability in the hard vacuum of space are best served together from within a thick-skinned, body-shaped, pressurised-balloon, minds at MIT are pursuing a spacesuit concept which is shaping up to be, quite literally the antithesis of this. Currently called the BioSuit this sleek Spiderman-meets-‘the Stig’ skin-tight suit is revolutionary in the extreme. Leaving aside the location of the breathing apparatus in the suit design for another day, MIT engineers are currently concentrating on a pressure suit exoskeleton that will restore the full range of body motion in which the spacesuits that have been worn for the last 50 years, have at times been greatly lacking.
Already striding in the right direction the nylon and spandex BioSuit hopes to achieve its goal by applying an ergonomically consistent pressure around the occupant’s body by means of suit impregnated structural tension lines. Based on Paul Webb’s 50 year-old Space Activity Suit notion and Arthur S. Iberall’s non-extension postulation, these fixed-mesh lines that follow carefully observed multi-directional and overlapping body muscular plains are held to never extend, no matter what physical position or range of movement the subject is moving through. The theory therefore surmises that if ‘wires’ within a skin-tight body suit were positioned perfectly above these deduced naturally-occurring body surface paths of non-extension, while crucially, simultaneously allowing flexibility between these lines for the body to change shape, the effect would be to adequately protect the human inside from the bodily-fluid-boiling effects of space, without any need for a large and potentially obstructive air-pressurised spacesuit. If it works, in one fell swoop full-pressure spacesuits will change from the clichéd puffy air pressure kind to mechanical pressure suits. So at what stage are Newman/Hoffman’s team at with the BioSuit’s production and how soon might we see an astronaut wearing one? Further studies into the location of the non-extension lines through a range of other specific body movements are proceeding with the possibility of the non-extension wires also becoming a thermal heating network for the astronaut. It is hoped that the first space-worthy BioSuit will be ready in time to see the first manned mission to Mars.
(Article by Nick Parke, Education Support Officer)