Organizational Unit:

Space Systems Design Laboratory (SSDL)

Permanent Link

https://hdl.handle.net/1853/70747

Parent Organization

Organizational Unit

Daniel Guggenheim School of Aerospace Engineering

The Daniel Guggenheim School of Aeronautics was established in 1931, with a name change in 1962 to the School of Aerospace Engineering

ArchiveSpace Name Record

https://finding-aids.library.gatech.edu/agents/corporate_entities/1138

Full item page

Publication Search Results

Now showing 1 - 10 of 628

A Progress Report on the Pre-Phase A Design of HyperSat

(Georgia Institute of Technology, 2024-08) Lammens, Robert

The Georgia Tech Space Systems Design Laboratory is currently in the process of developing HyperSat. It is a 12U CubeSat designed to maneuver into a highly eccentric orbit with its periapsis inside the Earth’s upper atmosphere. This will allow the CubeSat to perform its primary function of traveling through the Earth’s upper atmosphere and collecting hypersonic CFD data. This paper details the design progress of the mission as of the end of the Summer 2024 academic semester, including a general overview of the spacecraft’s budgets for mass, volume, and data generation. The communications architecture is laid out with design decisions for the onboard comms hardware, the ground station availability, and the available time to beam down scientific data. Lastly, some brief observations on how the design of the CubeSat may affect the post-launch spacecraft operations procedures are provided.
Proposal for a Space Systems Design Lab Multi-Mission Operations Center

(Georgia Institute of Technology, 2024-08) Merrell, Bryn H.

This paper outlines the difficulties of building an integrated multi-mission operations center for Georgia Institute of Technology’s Space Systems Design Lab (SSDL) and provides recommendations for future growth. The two main categories to address are human and technical factors. For human factors, changes in documentation and social structure are proposed to reduce the loss of knowledge as students graduate, and changes to onboarding and networking are proposed to quicken student growth. On the technical side, Ground Data Systems (GDS) and cybersecurity optimizations can be adapted to work on multiple missions. Also, from previous work on Lunar Flashlight and VISORS, general lessons learned in each catagory can improve the MOC workflow. The SSDL has had great success in Mission Ops and has the potential to transition into multi-mission operations.
Optimizing the Time Between Reaction Wheel Desaturation Maneuvers

(Georgia Institute of Technology, 2024-06) Mayfield, Malachi ; Romero-Calvo, Àlvaro

Spacecraft equipped with reaction wheels require momentum management as part of nominal on-orbit operations. When chemical thrusters are used for dumping momentum, the maneuver may disturb sensitive payload operations. This paper presents an angular momentum management algorithm for planning the optimal desaturation strategy that maximizes the time between maneuvers. The algorithm is derived by applying solutions to the minimum enclosing disk problem to reaction wheel arrays. The algorithm provides a general technique for planning desaturation maneuvers, in contrast to current methods which are either too complex or too mission-specific. Simulation results show that its application can nearly double the time between maneuvers with respect to percentage based desaturation techniques.
Preliminary Assessment of a Pendulum Analogy to Model Low-Gravity Liquid Sloshing

(Georgia Institute of Technology, 2024-05) Feneche, Mathilde

The Apollo Command and Service Module is, along with the Saturn V rocket and the Apollo Lunar Module, one of the three major components of the Apollo program developed by the American space agency, NASA, which took place between 1961 and 1975 and which allowed the United States to send men to the Moon for the first time. The dynamics of the spacecraft’s rigid body and the motion of the propellant, or sloshing, in an ellipsoid tank, are coupled due to the large amount of liquid propellant. The interaction between the spacecraft’s rigid-body dynamics resulting with the sloshing motion leads to an anomalous flight path of the Service Module. This paper seeks to replicate the dynamics of the Service and Command Module separation. It also aims to present a simplified model of the fluid motion in the tank, as a simple pendulum. This analogy provides satisfying results for a certain range of propellant mass values. As the mass increases, model becomes more chaotic and results differ from what should be expected.
Operational Development of Rotating Propulsive Maneuvers for NASA’s Lunar Flashlight Mission

(Georgia Institute of Technology, 2024-05) Jordan, Graham ; Lightsey, E. Glenn

This paper details the processes used for developing rotating propulsive maneuvers for JPL’s Lunar Flashlight cubesat mission as told from the perspective of the mission operations team. The timeline of the Lunar Flashlight mission after launch as well as the early anomalies that spurred work on the rotating maneuver concept are detailed first. An overview of the cumulative progression of implementing the rotating maneuver concept on the spacecraft is further explored. Finally, the operational software, hardware, and procedural tools that were created and utilized to make this development possible are described in-depth, concluding with a detailed description of the implementation of ground-in-the-loop maneuvers.
VISORS Assembly, Integration, and Test Plan

(Georgia Institute of Technology, 2023-12) Krahn, Grace

The VISORS mission utilizes two 6U CubeSats to form a distributed telescope with a 40-meter focal length to study energy release regions in the solar corona. VISORS is an NSF-funded collaborative effort between a large number of universities, commercial suppliers, and institutions that is often challenging to manage, especially in a dynamic environment like AI&T. An AI&T plan can help give mission-level clarity on what must happen to assure spacecraft readiness and hardware robustness before delivery. This process is best visualized with an AI&T flow diagram, which can show sequential progression through the project objectives and event dependencies in an easily trackable manner. This paper describes a highlevel nominal sequence of events to provide a big picture understanding of the AI&T flow. Breaking down each block further, each subsystem’s progression from individual component development to integrated systems testing is visualized through colors and arrows. Different categories of testing are described and included on a subsystem and system level in the AI&T plan with objectives for each test outlined. Finally, lessons learned from AI&T are given to help the VISORS project planners to better estimate the time and personnel needed to plan for, write, and conduct procedures.
Space Object Tracking from CubeSats utilizing Low-Cost Software Defined Radios

(Georgia Institute of Technology, 2023-12) Mealey, Alex
VISORS Mission Orbit & Dynamics Simulation Using a Realtime Dynamics Processor

(Georgia Institute of Technology, 2023-12-01) Kimmel, Elizabeth

VIrtual Super-resolution Optics using Reconfigurable Swarms (VISORS) is a precision formation-flying mission which uses two 6U CubeSats with a Science Mode separation distance of 40 meters to emulate a 40-meter focal length diffractive optic telescope. Due to the novelty of the technology used to achieve the stringent relative positioning requirements, the dynamics of these orbits must be simulated to verify the concept of operations (ConOps), the commercial spacecraft bus flight software (FSW), the guidance, navigation, and control (GNC) formation-keeping algorithm, and the attitude determination and control system (ADCS) performance, among others. Verifying these aspects helps ensure that issues such as reaction wheel saturation, pointing errors, or collision risks, among others, do not arise during the mission. This paper describes the work done in simulating the spacecraft dynamics during the mission’s Science Operations using COSMOS to interface with the Realtime Dynamics Processor (RDP) and spacecraft bus Engineering Design Unit (EDU) provided by Blue Canyon Technologies (BCT).
The Orbital Calibration 2 (OrCa2) CubeSat Mission

(Georgia Institute of Technology, 2023-08) Gunter, Brian C. ; Gregoire, Alaric ; Badura, Gregory ; Valenta, Christopher

The Georgia Institute of Technology (Georgia Tech), in collaboration with the Georgia Tech Research Institute (GTRI), has developed the Orbital Calibration 2 (OrCa2) mission in an effort to improve space domain awareness. OrCa2’s external panels have precise and well-characterized reflective properties that will permit various calibration activities from ground-based optical sensors, with the goal of improving the tracking and detection of resident space objects (RSOs). OrCa2 is a 12U CubeSat designed, fabricated, assembled, and tested almost entirely in-house using GT/GTRI facilities. It will be regularly observed using Georgia Tech’s Space Object Research Telescope (GT-SORT). A number of experiments can be conducted with these measurements, such as pose estimation, validation of RSO trajectory propagations with complementary ground-based laser ranging data, multi-spectral analysis, low-light detection algorithms, and validation of atmospheric scattering models. An onboard imager will serve as both a low-accuracy star camera, as well as an on-orbit optical tracking system capable of RSO streak detection, with a mission goal of gathering simultaneous ground-based and space-borne tracking data of one or more RSOs. Additionally, the OrCa2 spacecraft will host an experimental radiation dosimeter, an experimental software defined radio (SDR) receiver, and an experimental power system. OrCa2 is currently manifested to launch in Q1 2024. An overview of the design, concept of operations, and expected outcomes of the mission will be presented.
Design to Delivery of Additively Manufactured Propulsion Systems for the SWARM-EX Mission

(Georgia Institute of Technology, 2023-08) Tong, Kevin ; Hart, Samuel T. ; Glaser, Mackenzie ; Wood, Samuel ; Hartigan, Mark C. ; Lightsey, E. Glenn

Recent progress in miniaturized spacecraft propulsion technology has allowed for the development of complex, multi-vehicle missions which enable the cost-effective realization of science goals that would previously have been prohibitively expensive. The upcoming NSF-funded Space Weather Atmospheric Reconfigurable Multiscale EXperiment (SWARM-EX) mission leverages these swarm techniques to demonstrate novel autonomous formation flying capabilities while characterizing the spatial and temporal variability of ion-neutral interactions in the Equatorial Ionization Anomaly and Equatorial Thermospheric Anomaly. SWARM-EX will fly a trio of 3U CubeSats in a variety of relative orbits with along-track separations ranging from 3 km to 1300 km. To achieve the required orbital variability, the mission uses a novel hybrid approach of differential drag and an onboard cold gas propulsion system. Mission requirements necessitate a propulsion system that provides each spacecraft with 15 m/s of ΔV and a maximum thrust greater than 5 mN in a volume of roughly 0.7U (7 cm x 10 cm x 10 cm). Unlike many other CubeSat-scale cold gas propulsion systems which are used to provide attitude control and perform reaction wheel desaturation burns, the primary objective of the SWARM-EX propulsion system (SEPS) is to provide ΔV during maneuvers. The Georgia Institute of Technology Space Systems Design Laboratory (SSDL) is conducting the design, assembly, and testing of three identical SEPS. By leveraging additive manufacturing technology, the propellant tanks, nozzle, and tubing are combined into a single structure that efficiently utilizes the allocated volume. The propulsion system uses two-phase R-236fa refrigerant as a propellant, which allows for the storage of the majority of propellant mass as a liquid to maximize volumetric efficiency. The final design allows for 17 m/s of total ΔV per spacecraft and a measured maximum thrust of approximately 35 mN for short pulse lengths at room temperature. Each individual propulsion system has a volume under 0.5U (489 cm3), making them among the smallest formation-flying CubeSat-scale propulsion systems developed thus far. Owing to their two-phase propellant storage and single nozzle, the SEPS have a high impulse density (total impulse provided per unit of system volume) of 176 N-s/L. Additionally, process improvements to mitigate known failure modes such as propellant leaks and foreign object debris are implemented. This paper describes the entire design-to-delivery life cycle of the SWARM-EX propulsion units, including pertinent mission requirements, propulsion system design methodologies, assembly, and testing. Major lessons learned for future small satellite propulsive endeavors are also detailed.