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HERMES: A Satellite Surrogate Communication Testbed for Ground-Station Validation Using Software Defined Radio and OpenC3 COSMOS
No full textPoster presented during the 2025 SmallSat Conference
Navigation Signal Generator for LEO-PNT on CubeSat Platforms
No full textPoster presented during the 2025 SmallSat Conference
Experimental Validation of Omnidirectional Interferometry for Space-Based Radio Source Localization
Get PDFPoster presented during the 2025 SmallSat Conference
Sustainable Satellite Servicing With 12U CubeSats: A Policy-Aware and Cost-Optimized Approach
No full textPoster presented during the 2025 SmallSat Conference
An Intelligent Tasking and Processing Chain for Generating Climate Resilience Insights Onboard
No full textPoster presented during the 2025 SmallSat Conference
Accommodating a Very Large Aperture Antenna on a Small Satellite: The Global L-Band Observatory for Water Cycle Studies (GLOWS)
No full textThe NASA Instrument Incubator Program funded the initial development of the Global L-band active/passive Observatory for Water cycle Studies (GLOWS) as a NASA Soil Moisture Active Passive (SMAP) data continuity mission. SMAP, launched in 2015, collected L-band radiometer and radar measurements over land and ocean using a large aperture reflector antenna [1,2]. SMAP observations have demonstrated utility in measuring sea surface salinity and ocean vector winds over the ocean, as well as sea ice thickness. While the SMAP quad-polarization radar failed soon after launch, the SMAP polarimetric radiometer continues to provide high quality radiometer measurements to the present.
To address the need for L-band radiometer data continuity and to provide radar measurements to support improved soil moisture estimates and L-band wind speed measurements, we have developed GLOWS which continues the science observations of SMAP at substantially lower cost [3].
SMAP employed a complicated 6 m diameter, offset-fed reflector antenna that rotated at 14 rpm. To reduce the cost of GLOWS, we use a newly-developed deployable membrane meta-material lens antenna [4]. This flat antenna is lightweight and rotationally symmetric. At launch the antenna is densely packed into a small volume. These features simplify accommodation issues to enable a much smaller support spacecraft. Advancements in electronics further enable us to minimize the size, weight, and power (SWaP) of the radar and radiometer components.
GLOWS measurements will support critical ocean measurements such as sea surface salinity (SSS), sea ice, and ocean vector winds. L-band wind speed measurements are much less affected by rain than higher frequency measurements, which makes them particularly valuable for wind measurement in tropical cyclones and hurricanes [4]
Development of the Optical Deep-Space Instrument for Navigation (ODIN)
Get PDFThe Optical Deep-space Instrument for Navigation (ODIN) is a customizable, multiple camera, multiple field-of view (FOV) software and hardware sensor package. The instrument and software design are intended to make optical navigation (OpNav) methods more widely available to small satellite missions.
The ODIN flight software will have autonomous functionalities such as target determination, attitude estimation, and horizon-based position estimation, while still offering the option for manual modes to ease mission operation constraints. The flight software is built in core Flight System (cFS) and is designed to be agnostic to camera selection and placement.
Currently, ODIN is in its second year of development under NASA’s University Small Sat Technology Partnership (USTP) program and has already passed multiple testing benchmarks, with a final goal of advancing the technology to TRL 6 (validation in a relevant environment). To demonstrate one potential ODIN instrument configuration at a reasonable size for a small satellite mission, a 2U prototype with two very wide-angle cameras and two narrow angle cameras was designed
EEETester – Reliable CubeSat Platform for In-Orbit Testing of the Space Heritage of Korean-Made EEE Parts
No full textPoster presented during the 2025 SmallSat Conference
Attitude Determination and Control System Development of ARICA-2
No full textARICA-2 (AGU Remote Innovative CubeSat Alert System - 2) is a 2U CubeSat designed to demonstrate a real-time alert system for transient astronomical events using commercial satellite networks. Astronomical transient events are difficult to predict when and where they happen and typically have short durations. Therefore, it is important to alert other observational equipments in real time about the occurrence of such events so that observers can perform follow-up observations.ARICA-2 satellite surveys the feasibility of commercial satellite communications, such as Iridium and Globalstar, at various locations in orbit to demonstrate the real-time alert system. We investigated the relationship between the communication success rate and the antenna direction by identifying the orientation in which ARICA-2\u27s antenna surface faces during commercial satellite communication. Based on this study, we concluded that the rotation speed of a satellite needs to be around 1-2 degrees/s to achieve a high success rate of communications for the Iridium satellite network. Therefore, we decided to perform detumbling of the satellite using three-axis magnetorquers to improve the success rate of commercial satellite communications. In addition, we determine the attitude on the ground by downlinking the data obtained from the gyro, magnetic, optical, infrared sensors, and GPS to understand the direction between the ARICA-2’s patch antenna and the commercial satellites
Aquatic Habitat Representation for Robust Water Resources Management and Fish Conservation Decision-Making
No full textWe rely on rivers to provide water supply, flood control, and hydroelectricity for people and to sustain aquatic ecosystems. The development of dams and reservoirs to provide water for people did not consider environmental impacts to rivers, leading to widespread decline of freshwater species and habitat. Improving environmental outcomes of water management is needed to protect and restore aquatic ecosystems. However, rivers are complex and variable, making them difficult to represent as objectives for water management. This dissertation explores approaches to improve aquatic habitat representation and environmental objectives for water resources management and river conservation and restoration.
Chapter 2 uses economic and environmental modeling to evaluate tradeoffs in Utah’s Bear River Basin between water supply for people, impacts to stream habitat for fish, and changes to Great Salt Lake with proposed water diversions and reservoirs. New diversions and reservoirs reduced summer stream habitat for threatened Bonneville Cutthroat Trout, and water diversions to the metropolitan Wasatch Front decreased Great Salt Lake level by over 4 m (11 ft) between 2000 and 2020. I demonstrate that conflicting economic and environmental objectives for the Bear River exacerbate current threats to Bonneville Cutthroat Trout and pose significant economic, environmental, and human health risks from a declining Great Salt Lake.
Chapter 3 evaluates how barrier removals reconnecting stream reaches for Bonneville Cutthroat Trout perform under uncertain stream temperature conditions in Utah’s Weber River Basin. Barrier removals were sensitive to stream temperature data uncertainty for reconnecting summer coldwater stream habitats, and few barrier removals were also selected for reconnecting streams with suitable temperatures for fish growth. I demonstrate that uncertainty stream temperature conditions influence barrier removal selection and should be considered for restoring river connectivity.
Chapter 4 compares methods to predict fish passage at road-stream crossings for measuring connectivity in river systems. My methods for predicting road-crossing passability produced similar river connectivity estimates but vary considerably predicting fish passage for individual barriers. I demonstrate that simple methods for predicting fish passage at road crossings are sufficient to characterize river connectivity and highlight limitations for predicting fish passage to support barrier removal and river restoration