A Penn State research team was one of eight chosen to receive funding from NASA as part of the agency's University SmallSat Technology Partnerships (USTP) initiative within NASA's Small Spacecraft Technology program.
According to a NASA press release, teams were selected by the USTP initiative to mature new systems and capabilities in collaboration with NASA centers. At present, small spacecraft, or SmallSats, operate in low Earth orbit. In order to be used in other missions, SmallSats must be developed to operate within tight mass and power constraints. NASA's goal is that - in part through these collaborative partnerships - technological advancements will expand the potential of SmallSats and extend their capabilities to more complex Earth, lunar and deep space science and exploration missions.
The Penn State project is titled "Passive thermally deployed shape-memory alloy heat-pipe radiators for high-intensity small spacecraft."
Alexander Rattner, associate professor of mechanical engineering at Penn State, serves as principal investigator (PI) on the project. Penn State co-PIs on the project are Christopher Greer, assistant research professor of mechanical engineering; Sven Bilén, professor of engineering design, electrical engineering and aerospace engineering and director of the doctor of engineering in engineering program at Penn State; and Reginald Hamilton, associate professor of engineering science and mechanics. The team is closely collaborating with engineers at NASA's Glenn Research Center in Cleveland, Ohio.
"We are seeking to develop resilient, mass-efficient, passively self-deploying radiators with embedded phase-change heat pipe networks to enable emerging small spacecraft missions operating at high power levels of hundreds of Watts," Rattner said.
The team plans to produce thermal control radiators with embedded branching heat pipes that are additively manufactured in a nickel-titanium shape memory alloy, known as Nitinol. This specialty material has the ability to change shape as it is warmed above a transition temperature, which is called the shape memory effect. The shape memory alloy allows the radiators to be stored in a small, collapsed form. After the spacecraft launches and enters orbit, the heat from the spacecraft would warm the radiator and trigger the shape memory effect. This would cause the radiator to passively unfurl to a large, deployed footprint for effective heat rejection.
According to the research team, this new thermal control technology could advance the capabilities of small scientific and communications satellites operating in Earth's orbit and other domains.
"We are very excited to take on this research project," Rattner said. "This is an exciting opportunity to apply advances in materials technologies, additive manufacturing and thermal engineering to support new capabilities for Earth orbiting spacecraft and future cislunar and deep space missions."
