Digital Commons Network^™

Observing And Tracking The Great Pacific Garbage Patch, Chris Greenly, Hannah Gray, Hueson Wong, Samuel Chinn, James Passmore, Prisilla Johnson, Yaseen Zaidi

Small Satellite Conference

The subtropical waters between Hawaii and California are currently infested with an accumulation of plastic estimated to be twice the area of Texas, otherwise known as the Great Pacific Garbage Patch (GPGP). This paper presents a novel CubeSat mission to monitor the size, growth and position of the GPGP. At 1.6 million square kilometres, the GPGP is by far the largest and most serious accumulation of garbage out of the five patches littered across the world’s oceans. If we are to prevent further damage to the marine ecosystems, it is imperative we act with the utmost urgency. Leveraging recent technological …

The Mini Astrophysical Mev Background Observatory (Mambo) Cubesat Mission, Peter F. Bloser, W. Thomas Vestrand, Markus P. Hehlen, Lucas P. Parker, Darrel T. Beckman, Justin M. Mcglown, Lee Holguin, Kimberly K. Katko, James D. Sedillo, Anthony E. Nelson, Gregory K. Lee

Small Satellite Conference

The origin of the cosmic diffuse gamma-ray (CDG) background in the 0.3 – 30 MeV energy range is a mystery that has persisted for over 40 years. The Mini Astrophysical MeV Background Observatory (MAMBO) is a CubeSat mission concept motivated by the fact that, since the MeV CDG is relatively bright, only a small detector is required to make high-quality measurements of it. Indeed, the sensitivity of space-based gamma-ray instruments to the CDG is limited not by size, but by the locally generated instrumental background produced by interactions of energetic particles in spacecraft materials. Comparatively tiny CubeSat platforms provide a …

How Satellites Are Moving Beyond The Class System: Class Agnostic Development And Operations Approaches For Constraints-Driven Missions, Barbara Braun, Lee Jasper

Small Satellite Conference

Should we abolish the Class System? The Class A/B/C/D mission assurance and risk posture designations familiar to most satellite developers were established in 1986. They are used by both the Department of Defense (DoD) and National Aeronautics and Space Administration (NASA) to define risk and risk mitigation requirements for flight missions. However, many of today’s satellites are different – smaller, digitally engineered, designed for production, and increasingly destined for proliferated architectures. The rate of development is increasing while the uniqueness of the systems being built is decreasing.

The need to move faster and the ability to utilize, for the first …

5g Nb-Iot Via Low Density Leo Constellations, René Brandborg Sørensen, Henrik Krogh Møller, Per Koch

Small Satellite Conference

5G NB-IoT is seen as a key technology for providing truly ubiquitous, global 5G coverage (1.000.000 devices/km2) for machine type communications in the internet of things. A non-terrestrial network (NTN) variant of NB-IoT is being standardized in the 3GPP, which along with inexpensive and non-complex chip-sets enables the production of competitively priced IoT devices with truly global coverage. NB-IoT allows for narrowband single carrier transmissions in the uplink, which improves the uplink link-budget by as much as 16.8 dB over the 180 [kHz] downlink. This allows for a long range sufficient for ground to low earth orbit (LEO) communication without …

Rf Cables: The Overlooked Satellite Component, Andrew Kurzrok, Maria Calia

Small Satellite Conference

In comparison to the difficult work of payload design and system integration, specifying the correct RF cables seems all-too simple. A passive microwave component, the purpose of an RF cable is simply to transport an analog signal from one physical location on the satellite to another.

However, RF cabling design decisions can mean the difference between mission success and failure. RF cables can represent a potential weak link in overall system design because they are mechanically and electrically exposed. All too often, we find engineers have specified RF cables that either do not optimize for system performance or create mission …

Secure Space Mesh Networking, David Andaleon, Assi Friedman, Jonathan Wolff, Jeff Janicik

Small Satellite Conference

Innoflight’s Secure Space Mesh Networking development and prototyping efforts started at its incorporation over 15 years ago with a vision of establishing end-to-end Internet Protocol (IP) connectivity in and through space. A number of space industry trends have accelerated the demand for space networking: (a) the widespread adoption of enterprise-grade and cloud-based, IP-centric ground system architectures; (b) the accelerated growth of both commercial and government proliferated Low Earth Orbit (pLEO) constellations leveraging small satellites (SmallSats); (c) the maturation, miniaturization and commoditization of high-speed Radio Frequency (RF), Free Space Optical (FSO) Inter-Satellite Links (ISLs), and high-performance flight processors for aforementioned SmallSats; …

Globalstar Stx3 To Stx4/Spotx: An Evolution From Global Simplex To Global Duplex Communications For 1u Cubesats And Larger Vehicles, Andrew Santangelo

Small Satellite Conference

The STX3 module is used in devices from the LinkStar-TRK satellite radio system to SPOT locators used on the ground providing global beaconing services for a range of systems and applications such as cubesats, aircraft, ships at sea, and pipeline monitoring systems to name a few. For cubesats and small satellites the STX3 and the STX3 based LinkStar-TRK provides an invaluable low cost global data communications system. However a key drawback is the module only provides one-way “simplex” communications–there is not a mechanism to send messages and commands globally up to the satellite via the STX3 module. Per FCC regulations …

Non Data-Aided Carrier Tracking Techniques For Continuous-Phase Frequency-Shift Keyed Signals, Brendan Hill, Nazia Mozaffar, Salwan Damman

Small Satellite Conference

Communications between ground stations and nanosats in low earth orbit (LEO) require acquisition and tracking of large Doppler frequency offsets due to the relative velocity between the transmitter and the receiver. The Doppler frequency shift varies with time, reaching its fastest rate of change as the small satellite reaches its closest approach to the ground station. For phase modulated signals, a frequency offset estimate extracted from the band edge filters is used to correct for the Doppler shift. This approach encounters difficulties when it’s used to correct for frequency offset in continuous phase frequency shift keyed (CPFSK) signals. Optimized band …

Payload Testing Of A Weak Coherent Pulse Quantum Key Distribution Module For The Responsive Operations On Key Services (Roks) Mission, Cassandra Mercury, Sonali Mohapatra, Craig Colquhoun, Steve Greenland, Mikulas Cebecauer, Philippos Karagiannakis, Ahren Mctaggart, David Lowndes, Milan Stefko, John Rarity

Small Satellite Conference

Quantum Key Distribution (QKD) missions currently in development for space are expanding in number due to the increasing need for more secure means of encryption combined with the range limitations of terrestrial QKD. Most of these new missions are using smaller satellites to test their payloads. The ROKS (Responsive Operations for Key Services) mission is one such mission. It will utilize a 6U CubeSat bus and is set to launch in Q4 2022. A breadboard model of a 785nm weak coherent pulse quantum source module designed for ROKS, named JADE, was tested within a lab testbench environment with the mission’s …

Result Of Space Particle Monitor (Spm) On-Orbit Demonstration, Yasunari Koumoto, Kazuo Tanimoto, Yasuo Terakado, Tsutomu Ueno, Yoko Suzuki, Noriaki Oka, Masahiro Umesato

Small Satellite Conference

Space Particle Monitor (SPM) is a compact, lightweight and low-cost radiation measurement device that applies two PIN silicon semiconductor detectors. SPM was developed in the SERVIS (Space Environment Reliability Verification Integrated System) project under the Ministry of Economy, Trade and Industry (METI), and is mounted on JAXA RAPid Innovative payload demonstration Satellite 1 (RAPIS-1) launched in January 2019. We achieved the full success that the discrimination and energy content of electrons, protons, and heavy ions could be observed. This paper reports on-orbit demonstration results of SPM.

Improved Orbital Propagator Integrated With Sgp4 And Machine Learning, Zac Yung-Chun Liu, Scott Tarlow, Mohammad Akbar, Quentin Donnellan, Darek Senkow

Small Satellite Conference

The current industry standard orbital propagator, the Simplified General Perturbation Model-4 (SPG4), relies completely on physics-based orbital mechanics, can only provide accurate orbital predictions ~12 hours in advance. We developed a novel hybrid model, combining the SGP4 baseline with two machine learning estimators, autoencoder and random forest, in order to reduce the errors of the SGP4 propagator. The sources of errors in SGP4 propagators come from incomplete perturbation calculations and low-order of series expansions. The time-series nature of these error patterns are modeled by our machine learning estimators and then are used to make corrections to the SGP4 propagation, which …

Advanced Technologies: 7 Degrees Of Freedom Robotic Arm On Archinaut One, Kevin French

Small Satellite Conference

In Space Manufacturing (ISM) combined with robotic In Space Assembly (ISA) enables autonomous construction of space structures including spin gravity habitation rings, precision synthetic aperture radar (SAR) structures, and trusses for kilometer scale solar sails. Archinaut One (AO), designated as OSAM-2 by NASA, will demonstrate ISM and ISA through the ability to 3D print and robotically manipulate meter scale structures in orbit all from an Evolved Expendable Launch Vehicle (EELV) Secondary Payload Adapter (ESPA) class satellite. This work focuses on challenges associated with autonomous robotic ISA and ISM operations. Limited computational resources, robot satellite coupled dynamics, contact dynamics, and short …

Development Of A Cots-Based Propulsion System Controller For Nasa’S Lunar Flashlight Cubesat Mission, Nathan Cheek, Nathan Daniel, E. Glenn Lightsey, Sterling Peet, Celeste Smith, Daniel Cavender

Small Satellite Conference

The Lunar Flashlight mission is designed to send a 6U CubeSat into lunar orbit with the aim of finding water-ice deposits on the lunar south pole. The Glenn Lightsey Research Group (GLRG) within Georgia Tech’s Space Systems Design Laboratory (SSDL) is developing a low-cost propulsion system controller for this satellite using commercial-off-the-shelf (COTS) parts, with an emphasis on overcoming the harsh environment of lunar orbit through careful architecture and testing. This paper provides in-depth coverage of the Lunar Flashlight Propulsion System (LFPS) controller development and testing processes, showing how an embedded system based on COTS parts can be designed for …

Simulating The Storm Environment Responsible For Nepal's First Observed Tornado, Jonathan David Douglas Meyer, Binod Pokharel, Robert R. Gillies

Plants, Soils, and Climate Faculty Publications

A high-resolution numerical forecast model was used to simulate the meteorological conditions leading up to the March 31st, 2019 severe weather event that produced Nepal's first-ever observed tornado. The sparse meteorologic observations in the region capturing the storm environment limit the ability to anticipate another similar situation should the particular set of conditions present themselves again. This study presents a multifaced view of the storm environment through 1) a synoptic perspective provided by the Global Data Assimilation System (GDAS) reanalysis dataset and 2) a trio of progressively higher resolution one-way nested simulations (12 km–4km–1km) driven by GDAS boundary conditions to …

A Look Into User's Privacy Perceptions And Data Practices Of Iot Devices, Mahdi Nasrullah Al-Ameen, Apoorva Chauhan, M.A. Manazir Ahsan, Huzeyfe Kocabas

Computer Science Student Research

Purpose: With the rapid deployment of Internet of Things (IoT) technologies, it has been essential to address the security and privacy issues through maintaining transparency in data practices. The prior research focused on identifying people’s privacy preferences in different contexts of IoT usage, and their mental models of security threats. However, there is a dearth in existing literature to understand the mismatch between user’s perceptions and the actual data practices of IoT devices. Such mismatches could lead users unknowingly sharing their private information, exposing themselves to unanticipated privacy risks. We aim to identify these mismatched privacy perceptions in our work. …

A Versatile And Open-Source Radio Framework For The D3 Cubesat Mission, Carlos Carrasquillo

Small Satellite Conference

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 …

Ground Testing Of A Chip-Scale Atomic Clock For Maxwell Cubesat Flight Experiment, Luciana Schement, Caroline Dixon

Small Satellite Conference

This paper provides an overview of a flight experiment to observe the performance of a chip-scale atomic clock (CSAC) on a LEO cubesat. The results of this experiment will provide the basis for a realistic evaluation of the utility of the CSAC to support onboard position, navigation, and timing (PNT) applications for small satellites. The paper focuses on the goals and outcomes of ground testing performed on a CSAC in preparation for flight onboard the UNP-9 cubesat mission MAXWELL. The ground testing includes live sky testing, RF/GNSS simulator testing, and electromagnetic field testing.

Spacecraft Attitude Control Using Variable Inertia Reaction Wheels, Narottama Esser

Small Satellite Conference

This paper examines the usefulness of variable inertia reaction wheels (VIRWs) for spacecraft attitude control as compared to traditional fixed inertia reaction wheels (FIRWs). The equations of motion were derived for a spacecraft with FIRWs and VIRWs. Quaternions were used to represent the spacecraft’s orientation. A Lyapunov-based controller was derived and used to control the attitude quaternion and angular velocity of the spacecraft with the two control variables being the reaction wheels’ inertia and angular acceleration. A Simulink/MATLAB simulation was created to test the response of the FIRWs and the VIRWs to spacecraft reorientation maneuvers and detumble maneuvers. The results …

A Cubesat Power System Implementing A Zero Voltage Switching Resonant Buck Converter Design With Low Electronic & Radio Frequency Noise, Christine L. Page

Small Satellite Conference

Noise from power systems can be a limiting factor in how well scientific instruments on CubeSats can perform. Instruments such as microwave radiometers which are on TROPICS, TEMPEST-D, and IceCube, or wide-band software defined radios such as those used on AERO/VISTA for Earth auroral hiss observations, or precipitation instruments used on RainCube are all affected by electronic and radio frequency (RF) noise. Current hybrid DC/DC converter technologies can also be prone to failure and anomalies during flight. The GRACE mission had the converter fail due to high temperatures, which caused a reduction in switching frequency. This research project will provide …

An Analytical Approach To Modeling Spacecraft Potentials In Spice, Jason Powell

Small Satellite Conference

As the use of Langmuir probes on small satellites increases, so does the need to understand how spacecraft charging affects Langmuir Probe measurements. This paper explores the important relationship between probe and spacecraft surface area, and how it relates to the floating potential (or charge) on the spacecraft. Further, this paper discusses how a charged body’s interaction with the ionosphere can be modeled using custom circuit elements designed in SPICE. The SPICE models introduced are demonstrated with the SPORT spacecraft, a 6U mission that makes Langmuir probe measurements in concert with two electric field probes used to account for the …

Effects Of Gravitational Time Dilation In Short-Duration Balloon Satellite Flights, George Zhang, Aaron Flowers, Saleem Ali

Small Satellite Conference

The theory of general relativity stipulates that clocks located in a stronger gravitational field run more slowly than clocks located in a weaker gravitational field. This time dilation is often small and hard to detect. Its measurement requires precisely synchronized clocks accurate to the nanosecond level. An experiment aimed at detecting gravitational time dilation should last long enough to allow for detectable time drift to accumulate within the two clocks. This amount of time depends on the precision of the clocks used in the experiment. We describe the procedures followed to accomplish the task of measuring gravitational time dilation relying …

Constellation Forecasting Tools For Autonomous Operations, Alexander Dunn, Joe Miceli, Michael Reher

Small Satellite Conference

Large constellations are quickly becoming the norm in small satellite missions. These constellations are being designed and developed faster than ever before through the utilization of smaller, heterogeneous spacecraft. Often, these constellations provide increased resiliency and capabilities over their heritage, highly tailored counterparts. The ability to replace on-orbit assets quickly and with lower costs is an advantageous feature of these large smallsat constellations. With the advent of these new architectures, though, come increased complexity in mission operations. The management and monitoring of potentially hundreds of heterogeneous space assets can be extremely challenging and negate much of the cost savings using …

Automated Fleet Commissioning Workflows At Planet, Jose Angel Gutierrez Ahumada, Kelsey Doerksen, Stefan Zeller

Small Satellite Conference

In order to maintain the world’s largest Earth Observation satellite constellation and its goal of providing daily Earth coverage, Planet procures regular launch opportunities, each including up to several dozens of new satellites. Commissioning these batches of satellites, known at Planet as “flocks”, from deployment until imaging is done by a small team of operators and depends heavily on a number of automated workflows developed at Planet. Bringing all satellites to production in a safe and timely manner has a direct link to the productivity of the entire fleet. The main bottleneck during commissioning is ground station access time with …

Toward A Cohesive Management Of Earth’S Orbital Environment: Applying Policy And Collaboration To A Design For The Present And Future, Charles Lee Mudd Jr.

Small Satellite Conference

The response to Starlink solar reflectivity by some industry leaders, scientists, and other interested actors demonstrates the ability for diverse space actors to collaborate through dialogue and innovation to solve nuanced technological problems. These efforts should be encouraged and modeled to implement a response to and prevention of future dynamics that affect Earth’s orbital environment. In a separate but related context, the Federal Communications Commission (“FCC”) proposed and implemented new regulations regarding orbital debris. In 2021, the final regulations on orbital debris mitigation should be adopted, published, and implemented. This context suggests that the policy climate within the FCC should …

Design And Validation Of An Autonomous Mission Manager Towards Coordinated Multi-Spacecraft Missions, Antony Gillette, Alan George, J. Patrick Castle

Small Satellite Conference

For ambitious upcoming aerospace missions, autonomy will play a crucial role in achieving complex mission goals and reducing the burden for ground operations. Standalone spacecraft can leverage autonomy concepts to optimize data collection and ensure robust operation. For spacecraft clusters, autonomy can additionally provide a feasible method of ensuring coordination through onboard peer-to-peer scheduling. However, in exchange for providing flexible mission capabilities and operational convenience, autonomy introduces additional uncertainty and software complexity, which complicates the mission assurance process. This research presents a framework for designing and testing schedules consisting of heavily constrained tasks.

The core of this framework, the Schedule …

Arctic Weather Satellite, A Microsatellite Constellation For Improved Weather Forecasting In Arctic And Globally, Bastiaan Lagaune, Sten Berge, Anders Emrich

Small Satellite Conference

A consortium led by OHB Sweden has started the implementation of a prototype satellite for a possible constellation mission called Arctic Weather Satellite (AWS). This constellation of small satellites in low polar orbits would provide frequent coverage of the polar regions to support improved nowcasting and Numerical Weather Prediction (NWP) of the Arctic and Antarctic regions. The AWS mission is designed to be complementary to the existing polar-orbiting, meteorological satellites (e.g. MetOp and MetOp Second Generation (SG)), providing additional atmospheric sounding information to improve NWP on a global scale. The 120 kg AWS prototype satellite will fly in a ~600km …

The Autonomous System Architecture Of The Small Sar Satellite Operation System And On-Orbit Autonomous Operation Experiences, Toshihiro Obata, Motoyuki Arai, Shoichiro Asada, Tomoyuki Imaizumi, Yutaka Suzuki

Small Satellite Conference

We are developing a small SAR (Synthetic Aperture Radar) satellite for our commercial solution business. Our goal is to deploy at least 30 small SAR satellites in orbit and enable frequent and persistent observations until the Mid 2020s. We launched the satellite on 15th December 2020 by Rocket Lab's Electron. We waited for a month until we took the first image to confirm the complete evacuation of the residual air and contaminations to prevent any hazardous electrical discharge. We took the first image on 8th February. The satellite is now operating in a fine state and acquiring images requested by …

Satellite Constellations - 2021 Industry Survey And Trends, Erik Kulu

Small Satellite Conference

Large satellite constellations are becoming reality. Starlink has launched over 1600 spacecraft in 2 years since the launch of the first batch, Planet has launched over 450 in total, OneWeb over 200 and counting. Every month new constellation projects are announced, some for novel applications.

First part of the paper focuses on the industry survey of 251 commercial satellite constellations. Statistical overview of applications, form factors, statuses, manufacturers, founding years is presented including early stage and cancelled projects. Large number of commercial entities have launched at least one demonstrator satellite, but operational constellations have been much slower to follow than …

The Aero-Vista Interactive Spectrogram Display: An Original Software Solution For Scientific Operations Of Twin 6u Cubesats, Andrew Langford, Mary Knapp, John Swoboda, Ryan Volz, Phil Erickson, Frank Lind

Small Satellite Conference

Led by MIT Haystack Observatory, the AERO and VISTA twin 6U CubeSats launching in 2022 will study the auroral regions of the Earth in the medium and high radio frequency bands. Novel vector sensors, developed by MIT Lincoln Laboratory, will produce hundreds of gigabytes each day while conducting independent and joint (interferometric) observations of auroral phenomena such as auroral kilometric radiation. With a limited number of downlink opportunities and volumes on the order of gigabytes, mission operations require a tool to guide scientific processing and downlink decisions. The AERO-VISTA Interactive Spectro-gram (AVIS) Display, developed through open-source Dash Python and Digital …

Developing A Prototype Ground Station For The Processing, Exploitation, And Dissemination Of Pleo Sensor Data, Jennifer Wilbur, David Simenc, Eric Principato, Travis Williams, Jason Hamant, Matthew Mchugh, Sander Malmquist, John Maloney, Debi Rose, Dan Rossiter, Paul Wood

Small Satellite Conference

The Air Force’s Space and Missile Systems Center (SMC) recently executed a quick-turnaround (16 month) effort through the Defense Innovation Unit to develop a prototype ground architecture demonstrating low-latency processing, exploitation, and dissemination of data collected by notional multi-phenomenology sensors hosted on small satellites in a proliferated LEO constellation. This effort, led by the Southwest Research Institute and supported by teammates, Amazon Web Services, SpaceX, and SciTec, Inc., involved the modeling and simulation of a variety of different OPIR, EO/IR, and SAR data streams; transporting these data via space and ground networks; processing the data in the AWS cloud environment; …