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A Focus on Student Education: Determining Student Attitudes Towards Transparent Autograding and Developing Artificially Intelligent Tools to Help Students Succeed
Get PDFThis thesis is composed of two parts both relating to helping students succeed. First, the focus is on determining how we can help students feel more comfortable using an AI tool that can provide them immediate feedback. Second, machine learning algorithms are explored in relation to tracking student tasks to encourage healthy study habits.
The development of effective autograders is key for scaling assessment and feedback. While AI based autograding systems for open-ended response questions have been found to be beneficial for providing immediate feedback, autograders are not always liked, understood, or trusted by students. Our research tested the effect of informing students about key aspects of the autograder on their attitudes towards those autograders. Providing more transparent information about the autograders increased students\u27 perceptions of how effective the autograder was at grading their work, but did not improve other related attitudes—such as willingness to be graded by them on a test—relative to the control group which was not given extra information about the autograder. However, this lack of impact may be due to higher measured student trust towards autograders in this study than in prior work in the field. We briefly discuss possible reasons for this trend.
The second chapter of this thesis addresses the issue of students struggling to maintain focus on tasks. This chapter\u27s research explains the development process of a tool aimed to help teach students to focus by providing them with scaffolds so they can practice focusing. Prior research has used keyboard and mouse data to track user affective states and intentions, but task tracking software primarily has used application information for accurate classification. Using the Behacom dataset, this paper explores the training of various machine learning models on keyboard, mouse, and system data. Through feature selection and training machine learning models, this research is successful in developing a model to accurately classify user application usage. This information can then be used to determine if a user is on or off task in a way that maximizes user privacy
Still The Last Best Place ?: Concentrated Ownership, Amenity Migration, and Community Change in Southwest Montana
Get PDFAcross the American West, amenity rich areas have been grappling with population growth, economic shifts, and associated community impacts. Amenity migration, the movement of wealthy suburban and urban individuals to rural areas for the natural amenities and slower paced life, has contributed to much of the change in amenity rich rural places. However, recently, a new process has begun occurring simultaneously with amenity migration. New high net worth (HNW) individuals have been purchasing large parcels of land, often through the acquisition of multiple ranches that are thousands of acres. Little is known about how these new HNW owners impact the places they purchase land in. This dissertation uses four empirical chapters to explore how residents of a rural county in Southwest Montana are perceiving, experiencing, and responding to increased HNW ownership in their county.
Chapter 2 describes the modified drop-off/pick-up (DOPU) survey method used to collect data in Beaverhead County. The modified method included no contact drop offs, hand-written notes, and the option to complete the survey via Qualtrics. Results indicate that a modified DOPU maintains a relatively high response rate while lowering survey costs. Chapter 3 uses data from the modified DOPU survey to explore how residents of Beaverhead County are perceiving and experiencing increased HNW ownership and how that contributes to their view of the future of Beaverhead County. Results show that the HNW ownership has similar community level implications to amenity migration, but scaled up, and residents remain concerned and uncertain about how new owners will impact the landscape. Chapter 4 uses open-ended responses to the survey question “how do you define a Montanan?” to understand how place identity is changing due to amenity migration and increased HNW ownership. In Beaverhead County, the identity markers of a Montanan are shifting away from being based on time spent in Montana and towards the values that a person holds. Chapter 5 suggests that rural sociologists need to expand their view of rural places to account for hope by providing evidence of collective work towards a shared future in Beaverhead County
Mission Highlights From Deep Purple and the Pathfinder Technology Demonstrator-R
Get PDFDeep Purple is a satellite payload equipped with co-boresighted Ultraviolet (UV) and Short-Wave Infrared (SWIR) telescopes. The payload is hosted on the 6U Pathfinder Technology Demonstrator-R (PTD-R) CubeSat. PTD-R launched on August 16, 2024, into a Sun-synchronous orbit with an altitude of 520km. After successfully exercising basic inertial and Earth-based imaging with Deep Purple, more sophisticated modes that involve tracking Resident Space Objects (RSOs) were demonstrated. This paper highlights the unique sensing capabilities of PTD-R and outlines some of the mission successes achieved over its 10-month campaign. The latter include follow-on imaging campaigns coordinated with LLNL’s other on-orbit SDA demonstration satellite, GEOstare SV2
Telemetry Handling & Extensible Satellite Environment for a Unified System (THESEUS) for the Operation of ONGLAISAT
Get PDFThe recent increase in small satellites and diverse satellite missions has heightened the need for flexible and highly reliable ground station software. However, most existing open-source ground station software is implemented with the entire system in mind, making it difficult to accommodate diverse missions. Even when accommodating diverse missions, it is necessary to edit configuration files with a wide range of descriptions or make internal service modifications. Furthermore, as the number of available ground station services increases, there is an urgent need for systems that can support a wider range of interfaces. In addition, modern satellite development requires flexible support for diverse use cases, such as ground testing, software-in-the-loop simulation (SILS), and hardware-in-the-loop simulation (HILS). To address these needs, the proposed system THESEUS (Telemetry Handling & Extensible Satellite Environment for a Unified System) is highly modularized, with functions such as database logs and user interfaces divided into small, independent components. The proposed THESEUS system adopts a highly modularized design that divides functions such as database logs and user interfaces into small independent components. This design allows for easy reconfiguration in response to changing requirements from the development stage to the operational stage (ground testing, SILS, HILS, and production operations). In this presentation, we will introduce open-source ground station operation software that has been redesigned from a system already in use at our laboratory. This system adopts a scalable, distributed architecture that automatically establishes connections with available ground stations based on satellite orbit information and can switch operations as needed. Furthermore, a versatile API and cache server enable flexible changes to operational sequences. Furthermore, the distributed architecture, in which each component is independent yet interconnected, makes it easy to reconfigure modules according to operational requirements. For example, new data logging and convenience features can be developed as independent modules and seamlessly integrated into the overall system. This system has been applied to the operation of the ONGLAISAT satellite and has achieved good results in terms of both real-time performance and stability. Compared to conventional monolithic systems, the addition of new functions is simplified, secure connections with multiple ground stations are guaranteed, and rapid adaptation to operational scenarios involving different ground station facilities is possible. With its excellent scalability, the system can be seamlessly utilized in SILS, ground testing, in-orbit operation, and HILS phases. This paper discusses the main design and implementation points of the system, the results obtained from in-orbit operation, and prospects for future improvements
An Inter-Satellite Link Experiment on PEARL-1A and PEARL-1B CubeSats
No full textPEARL (Propagation Experiment using kurz-Above-band radio in Low earth orbit) -1A and PEARL-1B are two 6U XL CubeSats integrated by National Central University (NCU) are designed to perform space-to-earth and inter-satellite radio propagation channel experiments over Taiwan for educational training and scientific research. Both CubSats have the same structures and configurations. Each CubeSat will carry three payloads, an Inter-Satellite Link (ISL) payload, a Compact Ionospheric Probe (CIP), and a Perovskite Solar Cell (PSC) payload. The ISL enables over-the-horizon radio communication experiments, utilizing the Ka-band for both inter-satellite communication and space-to-ground communications. The CIP is an all-in-one in-situ ion sensor developed by NCU to measure global ionospheric ion concentration, velocity, and temperature especially to monitor ionospheric plasma irregularities resulted in radio scintillations. The PSC consists of perovskite solar cells designed to verify power efficiency by measuring their characteristics of I-V curves in space. Additionally, the CubeSats will be equipped with camera modules, which have been successfully tested on PEARL-1C and PEARL-1H missions. These two CubeSats are planned to deploy one by one almost in the same launch and are scheduled for Q1 2026, the Transporter-16 rideshare mission
Microgravity Testing of a Thermal Start Basket for Propellant Repositioning
No full textCubeSat cold-gas propulsion increasingly relies on two-phase propellants stored in conformal tanks. However, state-of-the-art propellant management strategies for these systems result in significant portions of the tank being occupied by vapor, reducing the amount of storable propellant. They also require high power input for vapor expulsion, increasing mission complexity and limiting operational lifetime. These challenges highlight the need for a more robust propellant management approach. The VAporization for PrOpellant Repositioning (VAPOR) experiment investigates the feasibility of repositioning an ullage gas bubble of R-236fa using thermally-induced phase change in various propellant management devices (PMD). These devices utilize a heat source to vaporize propellant near the outlet, inducing pressure-driven bubble condensation in colder regions of the tank. Capillary structures are integrated to retain vapor near the heater and promote bubble coalescence, facilitating extraction and routing to thrusters. The effectiveness of three PMD designs, each equipped with a patch or cartridge heater, is evaluated in low-gravity conditions through parabolic flight tests. Results confirm the effectiveness of the thermocapillary PMDs in generating and retaining an ullage gas bubble, paving the way for a more reliable and efficient propellant management approach for future CubeSat missions
Sol3 - A Level 5 Self Driving System for Spacecraft
No full textPoster presented during the 2025 SmallSat Conference
Tracking the Unseen: Identifying LEO Satellite Interference for Radio Astronomy
No full textPoster presented during the 2025 SmallSat Conference
Extended Testing of a Steam-Powered Propulsion System for Rapid-Orbit Corrections: A Viable Alternative to Chemical Propulsion
No full textThe Steam Thruster One is an electro-thermal propulsion system capable of delivering a thrust level up to 20 mN, using 20 W of power and reaching a total impulse of about 1200 Ns in its 2U configuration. The system operates solely on low-pressure water, ensuring complete safety for integration and operations both on the ground and in space. The propulsion cycle involves converting liquid water into superheated steam, which is then expanded through a nozzle to generate thrust.
The propulsion system was tested in space in Q3 2023 and Q2 2024, where it successfully demonstrated short propulsion manoeuvres. However, for extended thrust applications, a dedicated ground functional test campaign was conducted to simulate a bigger orbit correction, and specifically a perigee-raising burn.
This manoeuvre scenario is directly relevant to the upcoming Artemis II mission, in which SteamJet’s propulsion system will be integrated aboard K-RadCube, a 12U CubeSat developed by Nara Space Technology. The satellite will be deployed into a highly elliptical orbit, where insufficient thrust capability would result in atmospheric re-entry, making timely and efficient orbit-raising manoeuvres essential for mission success. Electric propulsion despite being efficient, would lack the required thrust-to-time ratio for this application, while cold gas systems suffer from low specific impulse, making both impractical. Typically, such manoeuvres would rely on chemical propulsion for rapid orbital adjustments. However, this test demonstrated that the Steam Thruster One, operating on superheated steam from low-pressure water, can achieve the same objective. Providing an average thrust of 17.4 mN for 11 hours and 30 minutes, the system successfully generated the required delta-V to raise the perigee within the designated timeframe, confirming water-based propulsion as a viable and efficient alternative to chemical systems for time-sensitive orbit corrections.
This paper provides a detailed analysis of the functional testing performed, including the experimental setup, results, and lessons learned. The findings contribute to the advancement of water-based propulsion systems and their role in efficient, sustainable, and rapid-response manoeuvres for Small Satellites
Sardonyx: A Building Block Towards In-Space Assembly
No full textIn-space assembly and manufacturing (ISAM) is an enabling capability for future space missions, and one where small satellites can play an essential role. Of the many technologies needed for ISAM, the Sardonyx mission will demonstrate two: capture of noncooperative resident space objects and close-proximity, agile maneuvering. Sardonyx is a partnership between Saint Louis University, Cambrian Works and Bennett Research Technologies.
The baseline design consists of a single 12U-scale spacecraft carrying multiple deployable Objectives. Each Objective will expand to at least a meter in diameter and be gently released. The Sardonyx spacecraft will detect the target, maneuver to within a few millimeters and capture the target using a novel electrostatic adhesion technology. Through repeated experimentation across a range of closing velocities, angles and materials, the performance of the maneuvering system and adhesion system will be characterized.
This paper outlines the Sardonyx mission, including the concept of operations, mission architecture and key technologies. Particular emphasis is placed on the mission design process, and how the Saint Louis University team intentionally structured the mission objectives to match the capabilities and constraints of a university student-led program. Key technologies include close-range sensing, cold-gas thrusters, navigation algorithms, inflation and release and force measurement. Prototype development and ground testing will be highlighted, culminating in a schedule and plan for launch readiness in 2028