USC Viterbi students placed 2nd in this year’s AIAA Region VI Student Conference. The award, which included a 275 dollar cash prize, came in the team category for research highlighted in the paper entitled Design and Construction of a Low-Voltage Bradbury-Nielsen Gate. Team members included USC Viterbi astronautical engineering seniors Brandon Dillon, Kevin Sampson and David Torre, and mechanical engineering senior Lorenzo Laxamana.
The paper discussed how precise measurements could pave the way for more cost effective, reliable and accessible methods of improving spacecraft propulsion development. Electric thrusters are small, electrically powered propulsion devices that move spacecraft around in space. For most rockets or thrusters, the most direct way to measure their thrust is by putting them on a thrust stand, which is a seesaw-like instrument that uses torque to calculate force (from the device at the end of the stand). But what if the thrust is so small that the seesaw won’t move enough for accurate measurements?
With some fairly basic physics concepts, the students built a device that can help calculate thrust indirectly. Since charged particles (ions) are what come out of the thruster, the students are able to implement their device, a Bradbury-Nielsen Gate (BNG)— a type of electrical gate— to deflect them. By turning the device on and off periodically, the team can also periodically deflect the particles. Keeping a record of when the device is switched on and off offers the information necessary for the team to figure out how fast these particles travel from the thruster to a pre-determined point. This ultimately allowed them to back-calculate a measurement for thrust.
While this theory of calculation has existed for some time, this team differentiated itself by innovating the design and construction of the BNG by using simple machinery and relative few materials compared to a process usually described by much more elaborate machining techniques.
The conference was ultimately cancelled due to the coronavirus pandemic, so judging focused solely on the reports submitted by student teams.