There have been many great inventions over the last 50 years, and it’s hard to say what the greatest has been, but one invention that is at least up there on the list is the CubeSat. Invented in 1999 by California Polytechnic State University, San Luis Obispo and Stanford University’s Space Systems Development Lab, the small cube-shaped satellites have opened up access to space to anyone, from students to small companies to any individual or group with an idea for an outer space experiment. CubeSats are also being used by major space agencies, but the oft-3D printed cubes were originally designed as a way for students to send projects to space, and they still remain largely the domain of students of all ages.
NASA encourages students to develop and launch CubeSats with its CubeSat Launch Initiative, which selects CubeSat-based projects from high schools, universities and nonprofits to be sent into space. In March, NASA selected 11 research groups from around the country to partake in the initiative, two of which were from Cornell University’s Space Systems Design Studio. The two projects are called Pathfinder for Autonomous Navigation and Alpha CubeSat.
Aslan and his team used 3D printing along with off-the-shelf hardware to construct the CubeSat. The 3D printed propulsion system the team created has never been successfully implemented in the construction of a satellite before, so the launch of the CubeSat could potentially have major implications for 3D printing in satellite construction. The 3D printed propulsion system dramatically drove down costs for the team, Aslan said, and has the potential to do so for other satellites.
“Our goal for the Pathfinder for Autonomous Navigation project is to break down barriers that prevent small groups like university labs with limited funding from accomplishing complex space missions,” said student Stewart Aslan, the project lead of Pathfinder for Autonomous Navigation.
“Other small satellite attitude control systems with similar capabilities to ours generally cost close to $100,000 or more,” he said. “We have driven that cost down to $2,500 for our mission.”
3D printing was also used by the Alpha CubeSat team, whose satellite also has a 1 x 1 m light-sail that will automatically unfold in space. The sail is made from an extremely thin layer of Kapton, a thermally stable film, that can be pushed through space by radiation pressure generated by electromagnetic radiation. The light-sail will have four chip-satellites, or ChipSats, one on each corner. ChipSats are even smaller satellites than CubeSats.
“Our chip-satellites are the smallest free-flying spacecraft in the world,” said student Liam Crotty, the project lead for Alpha CubeSat. “Each is about the size of a cracker, weighs less than a nickel, and carries a suite of sensors for characterizing its environment. Our chip-satellites allow for [localized] sensing of a very large region of space, since they can be distributed over a wide area. Furthermore, they are so cheap that they can be used more recklessly…This is a new paradigm in space exploration.”
The deadline for the CubeSat project is early 2019. For the Pathfinder for Autonomous Navigation team, the priority is to prepare the CubeSat for a variety of launch conditions.
“Every component must be tested over and over in many different situations to make sure that no matter what happens after launch, the spacecraft will function as intended,” said Aslan.
The Alpha CubeSat team is still working on communications systems for the ChipSats.
“We simply don’t have much room for solar cells, so it’s hard to generate much power,” said Crotty. “As a result, our radio transmissions are very weak and it takes a lot of processing power on the part of the receiver to hear the signal. The team is working on technologies for improving the data rate by doing more sophisticated signal processing in the receiver stations.”
This is the ninth round of the NASA CubeSat Launch Initiative, and the satellites will be launching in 2019, 2020 and 2021. You can find the full list of teams selected to participate in this round here.
Discuss this and other 3D printing topics at 3DPrintBoard.com or share your thoughts below.[Source: Cornell Daily Sun]