Session
Frank J. Redd Student Competition 2021
Location
Utah State University, Logan, UT
Abstract
This paper details the design and implementation of the communications system for the Drag De-OrbitDevice (D3) CubeSat mission. The D3 mission aims to validate the effectiveness of a novel approach to aerodynamically-based orbital maneuvering and controlled re-entry. Using four deployable tape-spring booms that can be retracted to any intermediate length, the D3 can accurately modulate the ballistic coefficient profile of the CubeSat in low Earth orbit (LEO). To compute the necessary boom deployment and reproduce a desired trajectory, the guidance profile of the CubeSat must be actively generated, which itself is a very computationally intensive process. The guidance will therefore be generated in a local computer, condensed into a transmittable file, and uplinked to the D3 CubeSat.
In order to enable the transmission of telecommands, the execution of telecommands, and the collection of the CubeSat’s telemetry, robust radio libraries and protocols were developed to run on both the CubeSat’s onboard computer and the ground station. The ground station program, written in Python, interfaces with a terminal node controller (TNC), which itself interfaces with the ICOM9100 transceiver. The onboard radiolibrary runs was developed in C++ and built to be compatible with Linux. It interprets, executes, and responds to inbound telecommands when invoked using a single line of code. Both programs were developed using the same architecture and design principles, which can easily be ported over for other missions and applications. When fully tested, the software will become available for use by hobbyists, amateurs, and professionals for use in future CubeSat missions.
A Versatile and Open-Source Radio Framework for the D3 CubeSat Mission
Utah State University, Logan, UT
This paper details the design and implementation of the communications system for the Drag De-OrbitDevice (D3) CubeSat mission. The D3 mission aims to validate the effectiveness of a novel approach to aerodynamically-based orbital maneuvering and controlled re-entry. Using four deployable tape-spring booms that can be retracted to any intermediate length, the D3 can accurately modulate the ballistic coefficient profile of the CubeSat in low Earth orbit (LEO). To compute the necessary boom deployment and reproduce a desired trajectory, the guidance profile of the CubeSat must be actively generated, which itself is a very computationally intensive process. The guidance will therefore be generated in a local computer, condensed into a transmittable file, and uplinked to the D3 CubeSat.
In order to enable the transmission of telecommands, the execution of telecommands, and the collection of the CubeSat’s telemetry, robust radio libraries and protocols were developed to run on both the CubeSat’s onboard computer and the ground station. The ground station program, written in Python, interfaces with a terminal node controller (TNC), which itself interfaces with the ICOM9100 transceiver. The onboard radiolibrary runs was developed in C++ and built to be compatible with Linux. It interprets, executes, and responds to inbound telecommands when invoked using a single line of code. Both programs were developed using the same architecture and design principles, which can easily be ported over for other missions and applications. When fully tested, the software will become available for use by hobbyists, amateurs, and professionals for use in future CubeSat missions.
