Engineering Commons^™

A Bevel Gear Root Bending Stress Model, Edward E. Osakue, Rasoul Saneifard

Faculty Publications

A reversed Lewis root bending stress capacity model for bevel gears is presented. The model is developed from first principle based on the Tredgold’s approximation of a bevel gear. The approximation conceptually transforms a bevel gear into a spur gear. The load distribution of the bevel gear facewidth is assumed to be triangular so that the stress at the gear is constant over the facewidth. Six design cases of root bending stress computations from different references are done using the new and AGMA models. The stress estimates from the new and AGMA models were compared. The stress deviations associated with …

Investigations Of Conjugate Heat Transfer And Fluid Flow In Partitioned Porous Cavity Using Darcy-Forchheimer Model: Finite Element-Based Computations, Nasir Yasin, Shafee Ahmad, Muhammad Umair, Zahir Shah, Narcisa Vrinceanu, Ghadah Alhawael

Mathematics & Statistics Faculty Publications

The conjugate heat transfer and fluid flow has vast applications in thermal engineering, particularly for cooling in thermal devices, and automobile engines. This study investigates conjugate heat transfer in 2D enclosures, featuring thin solid fins attached to a porous bottom wall. The porous medium is considered isotropic and homogeneous by the Darcy-Forchheimer model, with fluid phases in local thermal equilibrium. The boundary conditions at the porous fluid interface ensure continuity of the velocities, stresses, temperature, and heat flux. The phenomenon is mathematically modelled by obtaining a set of partial differential equations. The finite element method (FEM) is used to perform …

Effect Of Manufacturing Process On Mechanical Properties Of Polyetheretherketone (Peek) Cranial Implants Produced By Single-Point Incremental Forming (Spif), Elizabeth M. Mamros, Ihab Ragai, Brian Young

Faculty Conference Papers and Presentations

Polyetheretherketone (PEEK) is one of the most commonly used materials for cranioplasty due to its biocompatibility, relatively high strength, and light weight. Cranial implants manufactured from PEEK sheets using the same manufacturing process, e.g., single point incremental forming (SPIF), will have differing part properties based on the selected polymer forming process. Three fabrication methods for PEEK sheets were investigated: extrusion, modified hot pressing, and injection molding. Material characterization specimens were extracted for tensile, impact, and differential scanning calorimetry (DSC) experiments. The PEEK sheets were also subjected to formability tests at room temperature using SPIF. Slight differences in ultimate tensile strength …

Investigation Using Single Point Incremental Forming (Spif) To Fabricate Patient-Specific, Titanium Orbital Floor Implants, Elizabeth M. Mamros, Lauren E. Blaha Md, Christian A. Kauffman Md

Faculty Conference Papers and Presentations

The floor of the human orbit is composed of thin bone that is prone to traumatic fracture. This leads to a loss of support for the eye, which can cause vision changes. Therefore, fractures may need surgical reconstruction using a thin, sheet-like implant. Titanium implants are available off-the-shelf in standard sizes, but fitting to each patient’s unique anatomy requires surgeons to cut, file, and bend these plates. This can be time-consuming and imprecise. To both save time and ensure a perfect fit for the patient, a custom plate can be created prior to surgery. This investigation focuses on single-point incremental …

Scalable Machine Learning Framework For Adaptive Irrigation Management Of Maize And Soybean In The U.S. Midwest, Precious N. Amori, Derek M. Heeren, Yeyin Shi, Eric Wilkening, Ivo Z. Goncalves, Guillermo R. Balboa, Daran R. Rudnick, Abia Katimbo, Randall S. Ritzema

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Conventional soil water balance (SWB) irrigation scheduling tools, such as FAO-56-based Spreadsheets and the Spatial Evapotranspiration Modeling Interface (SETMI), rely heavily on manual inputs and periodic field measurements, leading to delayed recommendations and missed opportunities to prevent crop stress. More critically, these tools lack the computational scalability and adaptability to leverage the high-frequency, high-volume datasets now available through modern sensing technologies. As precision irrigation increasingly depends on integrating spatially and temporally nuanced field information, there is a pressing need for decision-support systems that can process Big Data efficiently and respond in real-time. To overcome these limitations, we developed and validated …

Software, Utah State University Space Dynamics Laboratory

Space Dynamics Laboratory Publications

Agenda

• Workflow
• Version Control
• Reviews
• Testing
• Constraints
• Concepts
• Assurance

Test And Integration Facilities And Equipment Eat, Utah State University Space Dynamics Laboratory

Space Dynamics Laboratory Publications

Agenda

• Hardware Protection

• Why, When and How

• Hardware protection breakdown

• ESD

• Cleanrooms

• Procedures

• Training

• Hardware Handling

• School Equipment Guidance

• Training References

Defense In Depth Exercise (Didex) 25: Technology Quad Chart, Kori Moore, Troy Johnson

Space Dynamics Laboratory Publications

SDL poster for DiDEX 25

Assembly, Integration And Test, Utah State University Space Dynamics Laboratory

Space Dynamics Laboratory Publications

What is “AI&T”

• A continuous, iterative process of turning low level components into the system of hardware, software and ground tools that meet YOUR mission

• Teaching the engineering team to UNDERSTAND the system they’ve built

• It does exactly what it was designed to do, now figure out what that was…

• Verifying mechanical, electrical, data and software interfaces

• Does it fit?
• Does it talk?
• Is it on?

Advanced Doppler Wind And Temperature Sounder, Trent Newswander, Scott Bailey, Mark Hervig, Phillip Scott, Zack Hatfield

Space Dynamics Laboratory Publications

Introduction

• An advanced Doppler Wind and Temperature Sounder (DWTS) is being developed for flight on NASA’s Dynamical Neutral Atmosphere-Ionosphere Coupling (DYNAMIC) satellite

– Will provide the first comprehensive global dataset of winds and temperature in the mesosphere and thermosphere (40–250 km altitude)

– Designed and built by Space Dynamics Lab (SDL)

• The DYNAMIC mission aims to characterize the energy transfer between the ionosphere, thermosphere, and mesosphere

– Led by Scott Bailey from Virginia Polytechnic Institute and Sate University

– See his HELIOTECH DYNAMIC poster for more details

• DWTS observes the Doppler shift of atmospheric NO and ^{13 …}

Electrical Power System (Eps) Overview, Utah State University Space Dynamics Laboratory

Space Dynamics Laboratory Publications

UNP Presentation on Electrical Power Systems

F-Layer Parameters Derived By Airglow Emissions At Pituffik Sb, Greenland, Jessica Norrell, Ivana Molina, Michael Negale, Jeffrey Holmes

Space Dynamics Laboratory Publications

Atomic oxygen airglow has long been used as tracer for the peak height and electron density of the F-layer (e.g. Sahai et al., 1981). Tinsley and Bittencourt (1975) described a method by which OI airglow is used to determine F-layer parameters. They found that the square root of the column emission rate of an optically thin layer created by radiative recombination emission was proportional to the peak electron density of the F-layer.

An all-sky imager (ASI) was recently installed at Pituffik, Greenland (76.51˚N, 68.74˚W), with four filters relevant to this study: 5725, 6300, 7715 and 7774 Å. We have used …

Autonomy For Dark Swarms In Degraded Environments, Thomas J. Walls, Brad Petersen, Matt Didericksen

Space Dynamics Laboratory Publications

A system that manages electromagnetic emissions and signature by design to avoid detection

Ai Simulation Creation, John P. Wilson

Space Dynamics Laboratory Publications

Introduction - AI Simulation Creation

• Exploring the use of Artificial Intelligence (AI) in the form of a Large Language Model (LLM) to produce a simulation of a factory production facility with given parameters and calculated performance.
• Use Grok (Grok 4 Expert) and Claude (Sonnet 4.5) LLMs 
• Ask the LLMs to solve the problem analytically and then create a Python simulation to calculate the results.
• Answer the questions: 
• Can an AI do this?
• How do the results compare?

Delivering Mission Success, Utah State University Space Dynamics Laboratory

Space Dynamics Laboratory Publications

SDL Presentation on Delivering Mission Success

100 Days, Phil Hale

Space Dynamics Laboratory Publications

Organizational Overview

Total Employees: 1367

Command & Data Handling, Firmware & Software, Utah State University Space Dynamics Laboratory

Space Dynamics Laboratory Publications

UNP Presentation on Command & Data Handling, Firmware & Software

Work Experience At Space Dynamics Laboratory Summer 2025, North Logan, Erik Johnson

Space Dynamics Laboratory Publications

Space Dynamics Laboratory (SDL) is owned by Utah State University and is a non-profit organization. Their headquarters are in North Logan and have over 1,200 employees. SDL is a University Affiliated Research Center (UARC), that delivers custom engineering solutions in the military, space, and science industries.

Qualification Of Titanium 3d-Printed Volume-Optimized Propulsion Tanks For Small Satellites, Robert M. Fowler

Space Dynamics Laboratory Publications

SDL presentation on Titanium 3D-Printed Volume-Optimized Propulsion Tanks for Small Satellites

Time-To-Digital Conversion In The Lattice Certuspro Fpga For The Cape Instrument, Zakk B. Rhodes, James Cook, Cameron Weston, Daniel J. Gershman

Space Dynamics Laboratory Publications

A time-to-digital conversion (TDC) algorithm is implemented in a Lattice CertusPro FPGA to measure time differences between two incident pulses for science data acquisition in the CAPE instrument on NASA’s GDC mission. CertusPro provides sub-100 picosecond resolution with nearly linear results which is discussed with its other unique characteristics. Performance measurements and variation in timing due to parameters such as core voltage and temperature are presented.

Celis: Compact Eyesafe Lidar System, A Portable 1.5 Μm Elastic Lidar System For Rapid Aerosol Concentration Measurement: Part 2, Retrieval Of Particulate Matter Concentration, Kori D. Moore, Alan W. Bird, Michael D. Wojcik, Robert Lemon, Jerry L. Hatfield

Space Dynamics Laboratory Publications

SDL Poster on the CELiS Compact Eyesafe Lidar System

Using Distributive Networks Of Single-Frequency Hf Transmitters And Receivers To Measure Spatial And Temporal Ionospheric Perturbations, Riley Troyer, Kenneth Obenberger, Ivana Molina, Eugene Dao, Zsolt Balint, Eric Burnside, Kris Robinson, Jeffrey Holmes, Pavel Inchin, Jonathan Snively

Space Dynamics Laboratory Publications

We can track ionospheric disturbances using networks of single-frequency HF receivers. How can we best utilize these systems and networks?

High-Performance Small Satellites For Demanding Missions, Lance Fife

Space Dynamics Laboratory Publications

SDL Presentation on High Performance Small Satellites

Principles Of Modular Open Architectures For Enabling Future Capabilities, Jacob Christensen

Space Dynamics Laboratory Publications

What is Modular Open Architecture?

Vision

• Modular Open Architectures enable affordable and evolutionary capabilities

Principles

• Employ Modular Design
• Designate Key Interfaces
• Select Open Standards

Benefits

• Reduce schedule
• Reduce cost
• Faster upgrades
• Enhanced interoperability
• Increased competition
• Increased innovation

Thermal Infrared Earth Resource Monitoring Instrument (Thermi) Swap Reduction, Trent Newswander, Scott Hansen, Jed Hancock, Darrel Williams

Space Dynamics Laboratory Publications

SDL Presentation on THERMI SWaP reduction

Arctic Over-The-Horizon-Radar Ontic (Arothron): A Model Definition For The Support Of Radio Frequency Radars, J. Vincent Eccles, John Retterer, Jeffrey M. Holmes

Space Dynamics Laboratory Publications

The high-latitude and subauroral ionosphere regions are organized and disorganized by a number of competing processes of ionization, convective transport, and plasma instabilities. The complexity makes it difficult for physics-based models or data-assimilation methodologies to specify the ionosphere with sufficient resolution and accuracy to adequately support radio signal technologies during space weather disturbance events. External drivers of ionospheric ionization include solar EUV and X-ray irradiance, medium and energetic particle precipitation, and solar proton events. External drivers of plasma transport include convective electric fields for high density plasma at mid-latitudes (e.g., storm enhanced densities or SEDs) and parallel plasma motion driven …

Demonstration Of Coherent Optical Phase-Shift Keying With A Tapered-Diode Laser Amplifier For Free-Space Optical Communication, Charlotte K. Duda, Aaron Cross, Chadwick Lindstrom, Julie Smith

Space Dynamics Laboratory Publications

SDL presentation on Coherent Optical Phase-Shift Keying

Optical Coating Characterization System (Occs), Scott Hansen, Kendall Johnson, Dean Wada, Alan Thurgood

Space Dynamics Laboratory Publications

SDL Presentation on OCCS

Acoustic-Gravity Wave Evolutions And Layered Observables In The Mlt, Jonathan B. Snively

Space Dynamics Laboratory Publications

ERAU Presentation on the Model for Acoustic & Gravity Wave Interactions and Coupling (MAGIC)

Calibration And Systems Engineering Collaboration, John Wilson

Space Dynamics Laboratory Publications

Introduction – Why Am I Here?

• I am a systems engineer with nearly 40 years experience in the DoD world.

• Opinions offered during tabletop discussions at CalCon 2024 showed a lack of coordination between calibration engineering and system engineering.

•Sorry, where this happens systems engineers are to blame.

• Calibration: “Calibration is configuring and verifying a measuring instrument's accuracy to ensure its readings match a known standard.” (What Is Calibration?, n.d.)

•Is this really what y’all do? I am here to learn!

• Systems Engineering: “SE is an integrative approach to help teams collaborate to understand and manage …