PolySat, Cal Poly’s satellite launching organization, is writing a NASA proposal to launch its seventh cube satellite into space since 2008.
Sponsored by aerospace company Northrop Grumman, the seventh satellite is known as CP7. It also goes by DAVE, short for Damping And Vibrations Experiment.
Render courtesy of Polysat
Though PolySat’s 10th satellite was launched last January, CP7 wasn’t originally given a deadline, putting it on the back burner as other projects with stricter deadlines were given more focus.
Mechanical engineering senior David Baker is the project lead and mission manager of CP7.
“It’s a collaboration of a lot of undergraduate students working toward a common goal of getting a functional satellite around an experiment from an aerospace company,” Baker said.
Northrop Grumman tasked PolySat with creating an experiment inside of a one-unit cube satellite that tests particle damping in a micro-gravity environment.
“Damping in general is just limiting the vibration of an object,” Baker said. “So particle damping is a special type of damping and how that’s achieved is, in this case, putting tungsten powder particles at the end of a cavity of a cantilever beam.”
Inside CP7, three cantilever beams are fixed to the side of the satellite on one end, with the other end free to vibrate with a cavity at the end of each beam.
One of the beams acts as a control, with no particles inside of its cavity. The second beam’s cavity is filled 95 percent full with tungsten powder and the third is 99 percent filled. The three beams will be compared based on their accelerometer readings to see how effectively the particles inside can dampen the vibration in those beams.
“So when we vibrate these beams, in theory, the particles inside the cavities at the end should limit that vibration,” Baker said. “And based on that data, we can apply that to bigger scales, bigger satellites which are more expensive.”
Baker said limiting vibration is important in all satellites.
“In this case we’re just testing the effect of it, but satellites up there that have imaging equipment and stuff like that, you don’t want them to be vibrating at all,” Baker said. “So testing how effective this is, a lot of aerospace companies want that kind of data.”
Most importantly, Baker and his team are writing a proposal for Educational Launch of Nanosatellites (ELaNa) in the hopes of getting CP7 launched with NASA.
“So that’s what we’re in the process of writing right now, and that determines if this satellite will go up within the next few years,” Baker said. “So it’s a really big step in the process.”
CP7 is still in development mode and will undergo more testing.
“Vibes testing has already been done for it, which is vibration testing, testing if the structure holds up during flight conditions,” Baker said. “That’s pretty much where it sees the most force, is when it’s going up on the rocket.”
The next phase will be testing the satellite’s hardware with its software.
Electrical engineering senior Marshall “Maci” Miri started working on the electronic components of CP7 in spring of 2015.
“I started working on the layout of the board, so actually connecting all of the components when you put it on a circuit board and making sure a lot of the radio components were together,” Miri said.
While CP7 is close to completion, it isn’t fully built and prototyped yet. The current focus is on writing the proposal for ELaNA.
“What I’m most looking forward to is if we get accepted for the ELaNa launch,” Baker said, “because that would be a huge step in the process of getting this up into space.”