Students from on-campus organization PolySat successfully designed, built and integrated CubeSat DAVE, launched into orbit September 15 from Vandenberg Air Force Base. The student-run organization and research laboratory has been working on the launched satellite DAVE (Damping And Vibrations Experiment) since 2008.
A CubeSat is a miniaturized satellite made up of one or multiple 10cm x 10cm x 10cm cubes. Through the ELaNa (Educational Launch of Nanosatellites) program, Cal Poly, along with UCLA and University of Central Florida, were able to have their CubeSats attached to the Delta II rocket. This rocket also launched ICESat-2, a satellite mission part of NASA’s Earth Observing System, which will measure Earth’s changing ice sheets for climate change purposes.
3-2-1… and we have liftoff of @NASA_ICE’s #ICESat2 atop @ULAlaunch’s #DeltaII rocket 🚀. Tune in as we broadcast live from Vandenberg Air Force Base in California: https://t.co/MIVnfneKo2 pic.twitter.com/xLRiCVcfrK
— NASA (@NASA) September 15, 2018
Many students who worked on DAVE traveled to Lompoc for the launch and were able to watch from a VIP viewing area. Stavros Diamantopoulos, aerospace engineering senior, helped the base team monitor the launch while in Los Angeles, were he was was able to see the rocket traveling across the sky. Diamantopoulos, integration lead for DAVE, said he was particularly proud of PolySat for having a satellite orbiting space during Week of Welcome.
“There was a lot of adrenaline watching — we knew we had something on the rocket that was ours,” Diamantopoulos said. “It is really amazing to know something you helped made, something you have touched, is right now orbiting our planet. It works and was launched successfully.”
What is DAVE?
DAVE is a CubeSat, a miniaturized satellite made up of one or multiple 10cm x 10cm x 10cm cubes. DAVE is a 1U (one cube) CubeSat, roughly the size of a softball.
All satellites are comprised of two parts: the bus and the payload. The bus is the body and features of the spacecraft which protect and support the payload. The payload — the object of interest — is the part of the satellite that carries its purpose. DAVE’s payload is an experiment that will test the effects of particle damping in microgravity conditions.
Particle damping is a technique that stabilizes sensitive scientific instruments. The strategy is used successfully on Earth, but has never been tested in space. Particles are used to minimize or “dampen” vibrations in order to steady instruments — think cameras or telescopes — that need to be stable for precision.
Michael Fernandez, a physics junior who assisted in integration for DAVE, explains particle damping by comparing it to a McDonald’s ball pit. If someone were to directly shake you outside the ball pit, you would get the full effect of the force. However, if someone were to shake the ball pit with you in it, the balls would create a cushion, absorb some energy and cause you to move around less.
To test this principle in microgravity, DAVE’s experiment consists of three aluminum beams, small bars that each have a cavity filled with particles on one end. The amount of particles (a very fine tungsten metal dust) on each beam differs. The control beam has no tungsten, the other two have slightly different amounts of tungsten. Each beam vibrates and collects vibration data to send down to laboratory. If vibrations are weaker on the beams with tungsten, particle damping will be taking place.
Cal Poly students not only designed and built DAVE’s payload and bus, they also integrated DAVE and built DAVE’s depolyer. Integration is a process of check-ups to insure a satellite will be healthy and functional once in orbit. This is done through a series of tests and simulations. It also includes putting a CubeSat into its deployer — a small, spring-loaded box which is attached to the side of a rocket. A deployer holds the CubeSat inside and pushes it out into orbit once in space. PolySat designs and builds their own deployers known as P-PODs (Poly Picosatellite Orbital Deployers). While other colleges build their own CubeSats, deployer building is unique to Cal Poly’s program.
Even after DAVE is successfully in orbit, there is more work to be done. Students were in the CubeSat lab as early as 5 a.m. the day after DAVE’s launch in order to locate and communicate with it. Chris Gerdom, PolySat member and electrical engineering graduate student, believes communicating with spacecrafts in orbit is a crucial component of the CubeSat program.
“The big thing is this is all student-run, all of these satellites are managed and designed and built by students,” Gerdom said. “DAVE is one of our first in a while, which gives us a chance to start talking to a spacecraft again and get a whole new generation of students used to talking to spacecraft that are actually flying in space.”
PolySat members are primarily focused on locating DAVE at this time, which is difficult given DAVE is traveling at 7 kilometers a second. Students will only be able to communicate with DAVE when they know its exact location and there’s a good “pass,” which means DAVE needs to be unobstructed from the lab’s view of space. This only happens for a couple minutes every day.
Once communication is made, students will check the health of DAVE and be able to download and analyze vibration data, which will be compared to the control beam and particle damping ground tests. Downloading data is the primary mission objective, but once complete, students will move on to secondary mission objectives such as taking photos of Earth.
Cal Poly’s PolySat
PolySat is a student-run organization that works to develop CubeSats. PolySat has an on-campus laboratory located in building 196, room 101. Anyone interested in seeing the lab or hearing more about the organization can stop by for a tour. There is also an exact replica of DAVE in the lab available for viewing.
Fernandez hopes more students will be inspired by what PolySat is doing and show interest in joining.
“We want people who are motivated and curious. People who do well in here spend a lot of time in here, lots and lots of hours, and ask a lot of questions,” Fernandez said. “The opportunity is here for people, it’s accessible and it’s a hell of a good time. We’re here, we love space — come talk to us.”