SAN FRANCISCO — As NASA and Congress discuss potential destinations for future human spaceflight missions, engineers are developing a new generation of spacesuits that offer the type of protection and mobility astronauts would need to live and work in many different environments.
Although the future spacesuit design will be predicated on the precise destination chosen and exploration tasks planned, engineers are striving to develop spacesuits capable of meeting the anticipated requirements of potential missions, such as a journey to Mars. A Mars mission would pose many of the challenges astronauts may face during future exploration missions, including long-duration space travel, extreme weather and dust, said Amy Ross, advanced spacesuit assembly technology lead at NASA’s Johnson Space Center in Houston.
In April, NASA awarded a $4.4 million contract to ILC Dover of Frederica, Del., to design, manufacture and test the next-generation Z-2 spacesuit. Under an 18-month contract, ILC Dover plans to produce two versions of the suit for NASA Johnson. Both are designed to allow astronauts to perform tasks including walking, kneeling and picking up rock samples, but one features a hard composite shell covering the upper torso and the other features a Hybrid Upper Torso.
The Hybrid Upper Torso uses a metal composite frame covered with a special fabric designed to retain spacesuit pressure. The Hybrid Upper Torso will use replaceable components to achieve a custom fit to enhance comfort and mobility, said Phil Spampinato, ILC Dover director of technology development partnerships. ILC Dover plans to produce the Hybrid Upper Torso frame by melting successive layers of a metal composite, a process known as additive manufacturing.
Both versions of the ILC Dover Z-2 spacesuit are designed to operate at higher pressure than spacesuits currently used by international space station crews working outside the outpost. In contrast to current space station suits, which are designed to operate at 4.3 pounds per square inch, the Z-2 spacesuit will be designed for pressure of 8.3 pounds per square inch. That increased pressure will enable astronauts to work outside the space station without first spending hours breathing pure oxygen to remove nitrogen from their blood and prevent decompression sickness. Inside the space station, astronauts experience pressure of 14.7 pounds per square inch, the same level present at sea level on Earth.
NASA is scheduled to begin testing the Z-2 suit following its delivery in 2014. It will then be mated with a new portable life-support system being developed at NASA Johnson. With adequate funding and continued progress in the development and testing of the portable life-support system, NASA could begin testing a version of the Z-2 onboard the international space station as early as 2017, Ross said.
As the Z-2 proceeds through development and testing, a team comprising Draper Laboratory and the Massachusetts Institute of Technology (MIT) is working with NASA to identify technology that could offer continued improvement in spacesuit designs. Cambridge, Mass.-based Draper is using internal research funding to design a spacesuit that employs complex algorithms and control moment gyroscopes built into an external jetpack to help astronauts maintain stability while repairing spacecraft or exploring asteroids. The technology is designed to provide attitude control to offset the various torques and forces produced when astronauts turn wrenches or strike objects with hammers. Without the counterbalancing force of gravity, those simple actions can push astronauts away from their work.
While astronauts currently use tethers and jetpacks to return to their desired location, the new suit is designed to reduce the need for tethers, give astronauts greater range of motion and preserve jetpack fuel. If, for example, astronauts planned to spend several hours exploring an asteroid, they probably would not want to be tethered to a spacecraft, said Bobby Cohanim, Draper’s Mission Design Group leader.
Draper and MIT plan to test a prototype of the new extra-vehicular activity suit this summer in NASA Johnson’s Virtual Reality Laboratory.
In addition to the new extra-vehicular activity suit, Draper is looking for ways to improve the health and performance of astronauts working inside their spacecraft. In September 2012, Draper received $500,000 from NASA’s Innovative Advanced Concepts program for the second phase of a study of technology that could be integrated in an astronaut’s clothing to improve his or her ability to adapt quickly to a weightless environment without suffering from common side effects such as motion sickness and disorientation.
The two-year project, called Variable Vector Countermeasure Suit, seeks to create small sensors and actuators that could be incorporated in an astronaut’s clothing to simulate gravitational resistance. Draper plans to house inertial measurement units and control moment gyroscopes in modules slightly larger than a deck of cards that could be placed on an astronaut’s arms and legs. The components in each module would monitor velocity and orientation with respect to whatever direction an astronaut specifies and to produce counteracting forces.
By simulating the effects of gravity, the Variable Vector Countermeasure Suit could help astronauts adapt to new gravity environments and prevent the type of muscle and bone loss that often occurs during prolonged periods of weightlessness, said Kevin Duda, Draper’s principal investigator on the Variable Vector Countermeasure Suit.