Asteria Project Updates
The goal of this project is to produce a solid-fuel adamantane plasma thruster to be implemented on a satellite design. The overview of this project can be divided into four main stages of modeling and hardware testing . A small plasma thruster will be constructed and placed in a vacuum chamber to produce a plasma bloom. We hope to run a numerical study to increase the efficiency of the thruster, research the effectiveness of adamantane as a fuel source, and eventually produce a full-scale working propulsion device.
Initial Thruster Built
Two simplistic experimental thruster designs were created using two metal washers and clear plastic tubing. We attempted to minimize the output orifice to the best degree to ensure a plasma bloom could be seen. The plastic tubing is used to house a small amount of adamantane to limit contamination in the chamber.
We have Plasma!
The image to the right is the first test of the smaller thruster design. There was a large amount of outgassing from the wires and our office is still too large to clearly see the plasma bloom produced by the adamantane. We believe the chamber should be pumped down to 50mTorr to better our results.
By repositioning the wires inside the chamber and pumping down to 50mTorr we have been able to limit some of the outgassing. Additionally, we have further shrunk the output orifice for a more defined plasma bloom. To test for thrust we have positioned a small piece of aluminum foil strung from a protractor to measure displacement. Due to the small size of the thruster, the displacement is currently too small to measure with our current setup. Efforts are being made to devise a way to measure the pixel displacement in the videos collected from each test.
We have successfully measured the thrust created by our prototype by attaching a piece of reflective aluminum to the end of our pendulum, allowing a laser to be deflected when plasma is being emitted. After running a number of tests, the displacement indicates that our thruster is outputting 18 ± 4 μN of thrust. The next steps for a more accurate measurement are to construct a test stand with the thruster mounted on the pendulum.
Presentation at GEC
We had the opportunity to send two undergraduate students to give a talk at the Gaseous Electronics Conference. Here we were able to present our thrust results, discuss our plans for Cubsat integration, and get advice from numerous people in the field. We are thankful for this opportunity and hope to continue to attend these conferences.
Exploring CubeSat Integration and Redesigning our Thruster
As we plan to move to a new facility to improve our vacuum we have begun experimenting with various forms of steel plugs and membranes to ensure no propellant loss during spin-up. In addition, we have begun constructing a new thruster design with the help of 3D modeling and finalized the electronics for our new inverse pendulum thrust stand.
We plan to move to a new vacuum facility in January 2024 where we plan on taking direct thrust measurements using the stage 2 thruster design and an inverse pendulum thrust stand. From here we will characterize the effects of voltage and current change on our thrust measurements. A new team will also begin production of a Langmuir probe to characterize electron density.
In addition, we have recently submitted an abstract to the IEPC 2024 conference. We hope to present our current findings and discuss more about the benefits of our design for CubeSats.