Digital Commons Network^™

Mine Water Storage In Deep Strata: Temperature Responses And The Quantitative Identification Of Primary Permeable Intervals, Xue Jiankun, Wang Shuangming, Zhang Pingsong, Wang Xiaodong, Han Le, Wang Zhizhou, Wang Yutong, Wang Zhibo

Coal Geology & Exploration

Background Storage in deep strata represents an effective approach to treating high-salinity mine water in mining areas of western China. For this technology, the use of directional wells can significantly enhance water injection efficiency, while selecting primary permeable intervals with high injectivity as drilling targets is key to its successful implementation. However, the accurate identification of these intervals in deep strata remains challenging. Methods By analyzing the wellbore temperature variations in the injection well during water injection, a qualitative model was developed to evaluate primary permeable intervals based on wellbore temperature curves. Following the principles of momentum and energy conservation, …

Field Tests On The Capillary Barrier Effect Of Covers For Comprehensive Utilization Of Solid Waste In Waste Dumps, Duan Xu, Chen Chuangchuang, Qiu Xun, Wang Bo, Shi Luyu, Yan Hanyang, Zou Yu, Qu Jin, Hu Zhaojiang

Coal Geology & Exploration

Background In the arid and semi-arid regions of northwestern China, the open-pit waste dumps of mining areas suffer from severe water erosion and the limited water-holding capacities of shallow cover soils. This restricts the ecological restoration of abandoned mine lands. Capillary barrier covers can enhance the water-holding capacities of water storage layers due to the differential hydraulic properties at the interface between fine- and coarse-grained layers. However, both the feasibility of constructing layered covers by mixing solid waste slags from waste dumps with clay and the water regulation performance of the covers are yet to be verified in the field. …

An Experimental Study On The Compressive Shear Failure Characteristics Of Mining-Induced Fractured Rock Blocks In The Absence Of Lateral Confinement And Under Unilateral Confinement, Wang Wenxue, Zhang Shicheng, Li Linyang, Zhang Ruochen, Liang Yankun, Chang Jian, Pan Xuwei, Zhao Guizhang

Coal Geology & Exploration

Objective Rock bridges exert a controlling influence on the deformation, fracture field evolution, and structural stability of mining-induced fractured rock masses. Therefore, it is necessary to investigate their deformation and failure characteristics, as well as the underlying controlling mechanisms, under different confinement conditions. Such investigations will provide theoretical support for the safe mining of underground coal seams and the prevention and control of mining-induced disasters. Methods Mechanical models of fractured rock blocks containing rock bridges were established. Specimens with different fracture dip angles, rock bridge widths, and material strengths were prepared using rock-like materials. Furthermore, an independently developed compressive shear …

An Image Recognition And Multi-Parameter Quantitative Characterization System For Fractures In Roadway Rocks, Xiong Yu, Jiang Lichun, Kong Dezhong, Li Jinzhu

Coal Geology & Exploration

Objective Conventional measurement methods for rock fractures suffer from low efficiency and high subjectivity. On the other hand, simple image recognition techniques struggle to achieve high-precision multi-parameter integrated analysis of rock fractures in complex roadway environments. To address these challenges, this study aims to develop an image recognition and multi-parameter quantitative characterization system for rock fractures. Methods At the core of the system is the formulation of a combined image preprocessing strategy. Specifically, fracture segmentation is conducted based on adaptive threshold binarization, isolated noise points are removed using morphological opening, and median filtering is introduced to perform the refined polishing …

A Method Of Reflected In-Seam Wave Imaging Based On The Structural Similarity Index Of Adjacent Gathers, Wang Ji, Wei Zhongli, Ye Hongxing, Wu Guoqing, Liu Shuo, Niu Huan, Su Xiaoyun

Coal Geology & Exploration

Background Reflected in-seam wave detection represents a major method for exploring geological anomalies in underground coal mines. This method is well suited to detecting concealed structures (e.g., faults and collapse columns) within coal seams in the tunneling direction of roadways or along their side walls. In recent years, to meet the safety requirements of green mine construction, explosive sources have been substituted with mechanical hammer impacts in increasing reflected in-seam wave detection. However, compared to conventional explosive sources, hammer impacts exhibit significantly lower instantaneous energy intensity and consistency. These limitations lead to reduced quality of reflected in-seam wave imaging, thus …

A Seismic Prediction Technology For Coalbed Methane Sweet Spots And Its Engineering Application In The Ordos Basin, Zhang Mengbo, Li Fei, Zhang Dong, Peng Jiankang, Cui Xiaojie, Ni Na, Long Shengfang, Tao Yu, Zhu Jun

Coal Geology & Exploration

Objective Deep coalbed methane (CBM) reservoirs tend to exhibit significant tuning effects of thin interbeds, leading to challenging localization of actual coal seam boundaries, limited identification accuracy of micro-amplitude structures in the coal seam roof, and poor stability of the seismic responses of the reservoirs' gas-bearing properties. To address these challenges, this study investigated the No. 8 coal seam of the Benxi Formation in the Mizhi area, Ordos Basin. Accordingly, a method with the prediction of gas-bearing properties as the primary controlling factor was developed for the seismic prediction and comprehensive evaluation of CBM sweet spots. Methods First, the actual …

Optimizing Ball‐Milled Composites For Fast Energy Release Under Shock Compression, Siva Valluri, Edward Dreizin, Dana Dlott

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Microparticle additives containing both Al fuel and oxidizer, fabricated by arrested reactive milling (ARM), could potentially increase the power of energetic materials such as HMX because they contain premixed fuel and oxidizer. Optimizing shock reactivity requires exploring a vast parametric space encompassing composition, milling parameters that govern microstructural features such as intraparticle voids and fuel-oxidizer mixing, and the resulting inhomogeneous shock reactivity of individual particles. To present our approach, we used a model composition 8Al⋅3CuO, previously optimized for combustion. We milled powders and prescreened different prepared batches using differential scanning calorimetry (DSC) to rule out batches with significant pre-reaction. Then …

The Quantum Cubesat: A Perspective For Quantum Technology In Orbit, Natalie Pearson, Andrew Kelly, Curtis Talbot, Colin Aitken, Kevin Quillen, Sandy Provan

Small Satellite Conference

Motivation

The ability to measure, control and exploit quantum effects has shown significant potential to outperform classical devices across a variety of applications in computing, sensing and communication. However, quantum devices today typically depend equipment that is large, heavy, expensive and delicate. Bringing quantum capability to space requires a relentless focus on miniaturisation, ruggedisation and applicability. Focusing engineering efforts on the most promising technologies to realise their benefits in orbit is a crucial step in this process.

Systems Progress Overview Of Rosisat: The Radiation Orbital Shielding Investigation Satellite, Chase Patterson, Jacob Blanton, Jayden Mcdonald, Kylie Nager, Colson Walker, Francisco Crespo Cutillas

Small Satellite Conference

Exposure to space weather in the Low Earth Orbit (LEO) space weather environment poses significant challenges to both the integrity and longevity of orbital hardware, as well as the health of astronauts, driving the necessity for improved means of radiation shielding for future manned and unmanned missions. With a 1U CubeSat formfactor, ROSISat is a planned LEO mission that aims to characterize the radiation shielding capabilities of seven candidate materials. By comparing the shielding performance of each composite and constituent material, ROSISat will place a specific focus on correlating how molecular structure influences radiation shielding. Further, current simulations lack the …

Experimental Investigation Of "Structured Radio Wave" Propagation Using A Deployable Parabolic Reflector With A Uniform Circular Array, Makoto Ito, Tsukasa Funane, Yosuke Tanabe, Miki Yonehara, Hisatoshi Kimura, Keigo Nakamura, Yasuyuki Miyazaki, Satoshi Ikari, Shinichi Nakasuka, Ayako Torisaka, Koichi Watanabe

Small Satellite Conference

Poster presented at the 2026 Small Satellite Conference

Lego®-Based Cubesats For Space Outreach, Stefan Brandle, Joshua Brown, Evan Smith, Drew Nye, Sydney Reddy, Twidy Kwae, Kaiya Grzesiak, Matthew Roderer, John Hetz

Small Satellite Conference

Taylor University Computer Science and Engineering is building a satellite having a LEGO®-robotics-based payload.

Mission Goals

• Have university students build a novel ELEO satellite
• Demonstrate viability of LEGO robotics electronics in space for short-term low-altitude missions
• Enhance space awareness by capturing the public's imagination through integral use of LEGO in an actual satellite
• Identify partners willing to provide advice and promote this project
• Create additional pathways for K-12 and university student participation in building satellites and satellite-related projects
• Support other space-education organizations through a high-visibility satellite project
• Continue space outreach efforts in the spirit of the ThinSat project
• ThinSat was …

Reacquiring Satellites After Unknown Maneuvers In Sensor Blind Spots: A Physics-Informed Behavioral Framework For Closed-Loop Custody Recovery, Naushad Rahman, Niha Agarwalla, Hardik Patel

Small Satellite Conference

Operational problem

After a maneuver during a sensor blind spot, a pre­-gap catalog state may no longer be operationally sufficient. A null look at GS2 must become evidence for where the object could be­ – and where to task next – before access expires.

Validation Of Steering Law For A 4-Variable-Speed Single-Gimbal Control Moment Gyroscope Pyramid Cluster Via Spherical Air-Bearing Testbed, Kai Kuo Liao, Chih Ta Wu, Jen Hao Cheng, Po Hsun Yen, Shang Jung Lee

Small Satellite Conference

• VSCMG: wheel speed is commanded with gimbal rate — the extra DOF lets the cluster slide past singularities.
• HIL: a Helmholtz cage replays the on-orbit field and a solar simulator sets the Sun line.
• This work: HIL validation of a weighted-pseudoinverse steering law, 4-unit pyramid.

A Comprehensive Review Of Perovskite Materials For Electronic Device Applications, Md Abdul Kuddus Sheikh, Md Shazarul Islam, Daniel Drane, Hasina Huq

Electrical and Computer Engineering Faculty Publications

Perovskite materials have gained remarkable attention as promising candidates for next-generation electronic and optoelectronic devices owing to their outstanding optical absorption, high carrier mobility, tunable bandgap, and cost-effective fabrication. This review explores the recent progress and future potential of perovskite materials across different categories, including organic-inorganic hybrid perovskites, oxide perovskites, and all-inorganic perovskites, emphasizing their structural diversity and electronic tunability. Special consideration is given to various dimensional perovskites (3D, 2D, 1D, and 0D), where reduced dimensionality provides enhanced stability and unique quantum confinement effects advantageous for device performance. The rapid development of lead-free perovskites is also discussed as an environmentally …

Development Of Wavelength-Division-Multiplexed All-Optical Relays For Low-Earth Orbit Free-Space Optical Communication Networks, Travis Jones, Justin Cook, Chris Krush, Doruk Engin, Keith G. Petrillo

Small Satellite Conference

In this work, we designed, built, and tested an all-optical relay amplifier to enable a space-based all-optical backbone for laser communications networks. The design sought to optimize links for LEO-based networks incorporating appropriate span lengths and optical terminal specifications. We incorporate an add-drop multiplexer for rerouting signals and designed the system to be flexible over span lengths with a nominal range of 1,800 km. We performed several tests of the nominally 60 dB gain amplifier to assess link dynamics unique to free space optical communications (FSOC) including the impact of pointing jitter, nonlinearities, gain flattening, and wide-band filters on an …

Demonstration Of Bidirectional Tracking And Data Transfer With The Cubeisl Optical Communication Terminal, Jan Hildebrand, Hannes Zeihsel, René Rüddenklau, Jorge Rosano Nonay, Lukas Rodeck, Olman Quiros Jimenez

Small Satellite Conference

This paper presents the experimental results of a free-space optical link validating the capabilities of two integrated CubeISL terminals. The campaign serves as a verification of the tracking, pointing and acquisition of the terminals before launch of the CubeISL mission. The link was conducted over a distance of 6600 m between the rooftop of the DLR Institute of Communication and Navigation in Oberpfaffenhofen and a 80 m high radio tower in Schöngeising. To ensure robust link establishment, the system employed a Pointing, Acquisition, and Tracking scheme utilizing both a 10 kHz modulated beacon for initial acquisition and a Continuous Wave …

Recovery Of Grus-1e From Magnetic Torquer Loss Using Data-Driven Open-Loop Attitude Steering, Nader Ganaba, Takanori Iwata, Minoru Kurata

Small Satellite Conference

In typical low Earth orbit (LEO) operations, the inability to remove excess angular momentum often leads to the decommissioning of a satellite. This paper presents the on-orbit recovery of GRUS-1E, a hundred kg class Earth observation satellite in Axelspace Corporation’s GRUS-1 constellation. The recovery followed the permanent loss of magnetic torquer commanding capability, which in turn disabled the satellite’s nominal reaction wheel momentum unloading. In addition, the satellite experienced persistent disturbance torques that significantly exceeded the combined contributions predicted by standard models, including gravity gradient, solar radiation pressure, aerodynamic drag, and the estimated residual magnetic dipole moment. The magnitude of …

Spatial Reconstructability Analysis: Information-Theoretic Modeling Of Categorical Raster Data, David Percy

Dissertations and Theses

This research focuses on the application of Reconstructability Analysis (RA), an information-theoretic machine learning (ML) methodology, to categorical spatial data in Geographic Information Systems (GIS). RA was developed in the systems community with applications including classification, prediction, pattern recognition, and decision analysis. RA is implemented in OCCAM (Organizational Complexity Computation and Modeling), a software suite developed at Portland State University that analyzes discrete data in tabular form, with observations in rows and variables in columns. While RA has been successfully applied to a variety of domains, no systematic application to georeferenced raster data arranged in regular grids has been previously …

Comparison Of Cubesat And Pocketqube Mission Timelines And Costs, Benjamin Skinner, Brian Damitz, Nathan Ford, Brian Iverson, David Long

Small Satellite Conference

PocketQube missions promise to reduce costs, speed up development timelines, and increase pedagogical value. We compared this mission format to CubeSat mission to compare relative strengths and weaknesses.

Advanced Ai Deployment On Smallsats: A Mixed Precision Approach To Onboard Perception And Fpga-Gated Inference, Margaret Michelsen, Jackson Gardner, Shawn Jones, Jackson Kulik, Mario Harper

Small Satellite Conference

MOTIVATION:

SmallSats are asked to make time-sensitive calls (vessel detection, cloud filtering, debris tracking) but CubeSat-class compute is starved for power, memory, and radiation-tolerant silicon.

Most missions still downlink raw imagery for ground processing, costing hours-to-days of latency and scarce bandwidth. Running inference onboard means solving two separate problems:

• When to run inference: compute and power budgets can’t tolerate a neural network firing on every frame.
• Whether it fits when it does run: the model has to live inside a memory and compute envelope measured in megabytes, not gigabytes.

Tracking Assembly For The Pulse-A Optical Ground Station, Rodrigo Spinola E Castro, Ashley Ashiku, Elizabeth Rosario, Juan Ignacio Prieto Asbun, Robert Pitu, Tian Zhong

Small Satellite Conference

PULSE-A is the University of Chicago’s student-led 3U CubeSat mission to demonstrate a space-to-ground optical downlink at a data rate of 1 to 10 Mbps using circular polarization shift keying (CPolSK).

A Cubesat-Based Data Collection Architecture For The Catarina Constellation: Complementing Legacy Brazilian Data Collection System With Lora, Vitória Beatriz Bianchin, Carlos Augusto Porto Freitas, João Cláudio Elsen Barcellos, Gabriel Mariano Marcelino, Talita Sauter Possamai, Eduardo Augusto Bezerra

Small Satellite Conference

• The Catarina Constellation is a Brazilian CubeSat initiative created to enhance environmental monitoring and satellite-based environmental data collection across Brazil.
• The project was named after Hurricane Catarina (2004), the first recorded hurricane in the South Atlantic, which exposed the need for improved space-based monitoring of extreme weather events.
• The constellation aims to expand the Brazilian Satellite Data Collection System (SBCD) by evaluating new communication technologies, enabling a gradual modernization of the country’s environmental monitoring infrastructure.

Cubesats For Climate Change Monitoring (C3m): Demonstrating Interferometric Ir Payloads Scalable To Constellations, Miguel Nunes, Paul Lucey, Noah Thompson, Jharrell Sim, Samantha Mallari, Dennis Sarsozo Jr., Junjie Huang, Jaycee Hasegawa, Mari Murillo

Small Satellite Conference

• Project Objective: Develop a compact, low-power IR spectrometer for a modular 1U CubeSat.
• Mission Motivation: Enable timely monitoring of climate hazards, wildfires, volcanic activity, and greenhouse gases.
• Core Demonstration: Validated end-to-end integration and operation of a thermal IR payload on the Artemis CubeSat Kit.
• Constellation Vision: Establish a scalable, low-cost architecture for high-revisit climate monitoring.

Power Simulation Framework For Korucusat-2 Using Freeflyer, Sahil Singh, Annabel Rong, Mukund Karthikeyan

Small Satellite Conference

A FreeFlyer-based power simulation was developed for KORUCUSAT-2, a low Earth orbit CubeSat designed to monitor silicon-anode battery behavior in space. The spacecraft model uses body-mounted solar panels with five modules on each of the +X, -X, +Y, and -Y faces. The simulation integrates orbital propagation, Earth shadowing, Sun-incidence angle, ground-station visibility, mode-dependent subsystem loads, and battery-state propagation to estimate electrical margin. Battery watt-hours and normalized state of charge are updated at each 30 s step so that critical, low-power, operations, and transmission modes can be evaluated against stored-energy limits. The framework provides a traceable prelaunch test bench for power-system …

Toward Plug-And-Play Sensor Integration: A Multi-Protocol Hardware Bridge For Nanosatellites, Pawan Kumar, Moritz P. Heimbach, Shayarrn Khatiwada, Jiten Thapa, Marco Schmidt

Small Satellite Conference

COTS sensors speak many protocols; but the satellite bus understands only a few. An FPGA hardware bridge board reroutes heterogeneous sensor protocols (UART, SPI, RS-422, RS-485) to the single communication channel with minimum latency supporting plug-and-play with no bus redesign.

A Proposed Development Process For A Hardware-In-The-Loop Testing System For Cubesat Components, Vahini N. Patel, Victoria Coverstone

Small Satellite Conference

Hardware-in-the-loop testing systems, commonly known as FlatSats, are testbed systems in which spacecraft subsystems, such as the onboard computer (OBC), power system, attitude determination and control system (ADCS), and communications, are laid flat and interconnected as they would be in an actual spacecraft. This arrangement gives easy access to each subsystem, enabling hardware and software testing and troubleshooting without risking fully assembled flight hardware.

FlatSats are widely used throughout the aerospace industry, from government agencies like ESA and NASA to private companies and university research labs, due to their versatility in enabling parallel development. This accelerates timelines and reduces …

Helio: Ai Solar Weather Forecasting For Proactive Small Satellite Constellation Response, Kylie Nager, James Kirk, Cagri Kilic

Small Satellite Conference

Challenge:

Small satellite constellations in Low Earth Orbit (LEO) operate in an environment directly exposed to space weather while providing communications, remote sensing, positioning, and other critical services. Geomagnetic storms heat and expand the thermosphere, increasing neutral density, atmospheric drag, and orbital decay. These effects are especially hazardous during post-deployment and orbit-raising operations when satellites remain at low altitude with limited propulsion and recovery margins.

Operational Gap:

NOAA Space Weather Prediction Center products provide essential situational awareness, but satellite operators must still translate environmental forecasts into spacecraft-specific decisions. This translation can introduce operational delay particularly when protective actions must be …

Measuring Space Weather Through Nitrogen-Vacancy Diamond Quantum Magnetometry: A Cubesat Mission Exploration, Patrick Bailey, Alberto Diaz, Jacob Boutin, Austin Downey, Wout De Backer

Small Satellite Conference

1. The Challenge

• Solar weather is constantly changing with adverse effects on earth and the space around it
• Solar flares cause communication blackouts
• Coronal mass ejections can damage satellite hardware, and cause geomagnetic induced currents that can damage the power grid
• Difficult to measure these effects in real-time

Micro-Servicer Swarms For Responsive Smallsat Sustainment: The Sdaw Mothership Architecture, Wanjiku Chebet Kanjumba

Small Satellite Conference

The Challenge:

Sustaining The Mega-Constellation Era: LEO has shifted from a sparse domain into critical global infrastructure. With thousands of satellites on-orbit and tens of thousands more planned, sustainability is no longer guaranteed by launch activity alone; it depends on the ability to service, repair, and responsibly dispose of assets at scale.

• 7,500+ operational satellites in LEO (2024); 50,000+ projected within a decade
• 1,500+ trackable fragments from the 2021 Russian ASAT test; 1,700+ Starlink avoidance maneuvers followed
• ≥ 5 / yr large debris objects removed from LEO yearly to stabilize it (Liou & Johnson)

The Servicing Gap: MEV, OSAM-1, and …

Minimum Variable Speed Control Moment Gyros (Vscmg) Cluster Sizing For Full Three-Axis Smallsat Attitude Control: A Numerical Study, Khang Nguyen, Christopher Damaren

Small Satellite Conference

Small satellites demand high-resolution imaging, optical inter-satellite links, precision science — demand agile, accurate attitude control under tight mass, volume, and power.

Momentum-exchange actuators are the standard propellant-free solution:

• Reaction wheels: precise, but low torque authority
• CMGs: high torque, but singularity-prone
• VSCMGs: variable wheel speed and gimbal angle → high torque, added DOFs for singularity avoidance, dual RW/CMG operation

The gap: VSCMG research has focused on 4-unit pyramid clusters, whose redundancy costs actuator count, volume, and power — resources SmallSats can least afford. The minimum cluster size for practical three-axis control is not well established.