EQUiSat has now been in orbit for 29 months and deorbited in December 2020. Since launching EQUISat, BSE has been envisioning its next challenge.
In Fall 2019, we finally introduced the concept for our next satellite.

PVDX: Perovskite Visuals and Degradation eXperiment

Overview

Primary:
To perform an in-orbit test a novel type of solar technology, Perovskite Solar Cells (PSCs), for the first time. This involves characterizing the solar cells with electrical measurements and visual imaging.

Secondary:
To serve as a platform for direct interaction with space and lower the barriers of entry to the aerospace industry by increasing the accessibility of satellite design and construction.

The primary payload of PVDX is the Perovskite Solar Cells (PSCs). Through a collaboration with Dr. Nitin Padture of Brown University’s Materials science Department, BSE will 1) test these cells in space as an integrated member of PVDX’s power system and 2) monitor any degradation that occurs with electrical data and a visible light camera. Although electrical data can distinguish between multiple causes of degradation, it cannot distinguish between chemical degradation of the perovskite crystal and non-chemical factors such as microcracks or encapsulant failure. Since chemical degradation of the PSCs is associated with a change in color (from brown to yellow) of the cells, visible light imaging can be used.

The secondary, interactivity-based mission will be enabled by a dot-matrix display mounted on a side of the satellite, to create the ‘interactive’ component of our mission. BSE will enable anyone to upload and run their own sequences of commands on PVDX to control its arm, display, and camera. After their “program” is uploaded and run, the camera will capture and send down an image showing the results of their program. The image could show what’s on the display, an image of Earth, or any other view that was programmed!

An example program might move the arm such that the camera views the display, perform some computations on the satellite’s sensor readings, print the result on the display, and finally take a photo once the earth is in the background.

In December 2020, we submitted our application to NASA’s Educational Launch of Nanosatellites (ELaNa program. We found out that we were accepted in Spring 2021! We will launch PVDX in mid-2024. To that end, based on our experience with EQUiSat’s integration and testing process, we hope to have a minimum viable satellite by mid-2022.

PVDX

3U

6 Li-ion batteries

1 S-band and 1 UHF radio

2 processors, with one dedicated to camera data

EQUiSat

1U

2 Li-ion and 4 LiFePO4 batteries

1 UHF radio

1 processor

Progress

PVDX is undergoing a series of design reviews by experts and advisors in academia and industry. All NASA CubeSats participating in ElaNa go through the System Requirements Review, Preliminary Design Review, Critical Design Review,  Testing Readiness Review, and System Verification Review prior to launch. As of February 2022, PVDX is undergoing its Preliminary Design Review. PVDX’s Critical Design Review is scheduled for April 2022. All our reviews and review presentations are open-sourced and are available in the below Google Drive.

 

Our Structures team finished their first version of a flight chassis. It’s an especially modular design that splits the satellite into two halves about 15 cm long, and gives us easy access to satellite components.

They’re not done though! As we iterate on our other subsystems, changes to the chassis will be necessary. Additionally, Structures team is working to develop deployment mechanisms for the camera-holding arm and developing an attitude control method for pointing our satellite’s antenna towards the Earth.

Our Avionics team has a detailed block diagram of PVDX subsystems ready. Now, they’re working on prototyping their PCBs.

Our Software team is hard at work, readying themselves to face PVDX’s many technical challenges. Stay tuned for updates!

Our Ground Software team is hard at work, designing the PVDX app and the user interface that will allow us to send anyone’s message to our display and show it in space. Stay tuned for updates!