Synthetic muscle developed with PPPL scientists' help launches
Lenore Rasmussen’s dream of developing a synthetic muscle that could be used to make better prosthetic limbs and more responsive robots literally became airborne on Tuesday, April 14 at 4:10 p.m. when her experiment rocketed off to the International Space Station from Cape Canaveral in Florida.
Rasmussen developed the material at RAS Labs and has worked closely with researchers and engineers at the U.S. Department of Energy’s Princeton Plasma Physics Laboratory (PPPL) to develop the material’s ability to adhere to metal. The Synthetic Muscle™ could be used in robotics in deep space travel such as travel to Mars because of its radiation resistance.
“Based on the good results we had on planet Earth, the next step is to see how it behaves in a space environment,” said Charles Gentile, an engineer at PPPL who has worked closely with Rasmussen. “From there the next step might be to use it on a mission to Mars.”
Early Connection with PPPL
Rasmussen began working with PPPL in 2007 just four years after she started Ras Labs. She received her first patent for a synthetic muscle in 1998. It is a gel-like material called an electroactive polymer that can potentially mimic human movement because it can expand and contract to simulate the movement of muscles in humans. That ability would make it very useful in robotics and in developing better prosthetic limbs.
“We can’t explore space without robots,” Rasmussen said. “Humans can only withstand a certain amount of radiation so that limits the time that people can be in space, whereas robots particularly if they’re radiation-resistant can be up there for long periods of time without being replaced.”
Lew Meixler, the long-time head of Technology Transfer at PPPL, who retired in March, said he has enjoyed helping Rasmussen follow her quest. “That’s what entrepreneurs are,” he said. “They’re the dreamers who devote all their time, energy and resources to following their dreams.”
Rasmussen credits PPPL with providing help and support during critical points in her project. “It was and continues to be a wonderful resource not just because of the plasma physics but the people,” she said. “Charlie and Lew found ways to make things happen.”
At PPPL, Rasmussen solved a crucial problem: getting the gel, which can be as soft as jelly or as hard as rubber, to adhere to the metal electrodes. Initially working with Lew Meixler on a federal Cooperative Research and Development Agreement in the Plasma Surface Laboratory, she solved the problem by treating the metal (steel or titanium) with a plasma. This changed the metal’s surface and made the gel adhere more closely to the metal
PPPL was also involved with tests of the material last summer, when the material was exposed to over 300,000 RADs of gamma radiation. That is 20 times the amount that would be lethal to a human and was equivalent to a trip from earth to Mars and back. A second test of 45 hours was enough to be equivalent to a trip to Jupiter and beyond
Rasmussen and Gentile found that there was no change in the strength, electroacivity, or durability of the material due to the radiation, although there was a slight change in color. Tests on selected samples of the material found it was not affected by extreme temperatures down to -271 degrees Celsius, which is close to absolute zero, the coldest temperature possible in the universe.
Preparing for launch
Since then, PPPL staff members have been involved in planning for the launch. This involves mapping out each detail with military precision. Several PPPL staff members, along with Rasmussen and her staff, signed the back of the metal container or coupon holding the material. “All of the people who worked on the lab signed it and the coupon will go into space,” said Gentile. “So I’ll be up there with Gene Roddenberry.”
The Synthetic Muscle™ material was launched on the Falcon 9, a rocket carrying the Dragon spacecraft, both produced by Space X, which carried 4,300 pounds of supplies and payloads, including material for research experiments, to the International Space Station's U.S. National Laboratory. The nine-engine rocket propelled the Dragon into orbit where it met with the Space Station three and a half days later. Astronauts used the station’s 57-foot arm to reach out and capture Dragon at 7:10 a.m. on Friday, April 17. Additional information about the launch is available at http://www.nasa.gov/press/2015/april/research-for-one-year-space-station-mission-among-nasa-cargo-launched-aboard-spacex.
The material will be kept in a zero gravity storage rack in the U.S. National Laboratory on the space station for 90 days. The astronauts will photograph the materials every three weeks. When the material returns to Earth in July, it will be tested and compared with identical materials that remained on Earth.
The International Space Station is an international science laboratory in low Earth orbit where astronauts conduct scientific research in biology, human biology, astronomy, meteorology and other fields in a gravity-free environment. It has operated since November of 2000 with the cooperation of the U.S., Russia, many European nations, Japan, Canada, and Brazil. It is currently staffed by two astronauts from NASA, three cosmonauts from Russia and an astronaut from the European Space Agency.
Use as a prosthetic
Rasmussen is also exploring whether Synthetic Muscle™ could be used as a prosthetic liner. The vestigial limbs of amputees can expand and contract during the day and the Ras Labs material is designed to expand and contract so it could make prosthetics more comfortable. She recently received a grant from the Pediatric Medical Device Consortium at the Children’s Hospital of Philadelphia to research this possibility.
Ras Labs is a high tech woman-owned small business. Visit http://www.raslabs.com.
Princeton Plasma Physics Laboratory is a U.S. Department of Energy national laboratory managed by Princeton University.
© 2016 Princeton Plasma Physics Laboratory. All rights reserved.