Dayton Engineering
Sciences Symposium


List of Submitted Abstracts

* Note that appearance on this list does not guarantee that the abstract has been or will be accepted. All submitted abstracts will be reviewed for suitability and technical content.

Oral Presentations

Additive Manufacturing

Abstract ID: DESS2025-003

Enhancing compressive properties of Nylon 12 lattice structures made by Selective Laser Sintering

Ahkar Min Thant
Miami University
Nabin Bastola
Miami University
Muhammad P. Jahan
Miami University
Jianfeng Ma
St. Louis University

In modern engineering research, maximizing mechanical properties while reducing material consumption is a critical factor, and lattice structures (LS) have a unique design that allows them to be attractive on both fronts. The study of LS has also been greatly facilitated by developments in 3D modelling technology as it allows researchers to explore the innovative geometric designs of LS. To further expand our knowledge of lattice structures, in this study, three common LS were improved upon by adding a cross-reinforcement (CR) struts. The new LS are Auxetic Cross (AuxC), Auxetic-Hexagonal Cross (AuxHexC), and Hexagonal Cross (HexC). Using a Selective Laser Sintering (SLS) printer ‘Fuse 1’, the three common LS and three new CR-LS were printed to be experimented upon. After the experiments were conducted, it was found that the Hex structure had the highest mechanical properties in terms of elastic modulus, yield strength, maximum load, and energy absorption. Comparing the CR-LS to their LS counterparts, it was found that the CR-LS exhibited significantly higher maximum compressive strength. This was observed in their different failure mechanisms: the three LS failed in a layer-by-layer mechanism while the CR-LS failed in a catastrophic mechanism. The CR in CR-LS made the structure more rigid which explains why the CR-LS had a significantly higher maximum compressive strength. Moreover, the print variability among the three samples printed for each unique structure was also examined. The results showed that the samples of all six unique structures had consistent maximum load but had different total energy absorption as the brittle behavior of the structures. In conclusion, the results showed that the cross-reinforcement struts added to the common lattice structures improved their mechanical properties, especially in terms of maximum strength.

Abstract ID: DESS2025-010

Multi-track melt-pool dimensions and cooling rates prediction for Laser Powder Bed Fusion with Inconel-718

Rahul Singha Rathun
University of Dayton
Abdullah Amin
University of Dayton

Accurate prediction of melt pool geometry and cooling rates at part scale remains a significant challenge in Laser-based metal Powder Bed Fusion (PBF-LB/M) Additive Manufacturing. In this research, the commercial CFD solver Ansys Fluent is utilized to develop a reduced order model for accelerated prediction of melt pool metric and cooling rates. The reduced order model is developed by calibrating laser processing parameters against experimental benchmarks provided by the NIST 2022 AM-Bench study for Inconel 718. Single-track simulations are conducted to evaluate melt pool depth, width, solid cooling rate, liquid cooling rate, transition cooling rate, and time above melting. The calibrated parameters from a representative case are subsequently applied to multi-track simulations comprising 47 tracks, predicting melt pool morphology and cooling rates. The predictions are validated against experimental measurements completed by NIST. Therefore, a reduced-order modeling framework is demonstrated to enable rapid calibration and high-fidelity prediction, providing a computationally efficient alternative to purely physics-driven, expensive, and complicated thermal-CFD models. The results demonstrate that multi-track melt pool dimensions and cooling rates can be predicted from single track calibrated data with high accuracy, thereby facilitating efficient process optimization in metal AM.

Abstract ID: DESS2025-017

Studies of Gamma Radiation Attenuating Effects in Additively Manufactured Polymers

Lucas Clark
Wright State University
Ahsan Mian
Wright State University
Fahima Ouchen
Air Force Research Laboratory
Laura Davidson
Air Force Research Laboratory
Carrie Bartsch
Air Force Research Laboratory

Ionizing radiation is a high priority concern for long-term and deep-space missions. Radiation can damage sensitive electronics instantaneously or over time. Gamma rays are a type of radiation and are highly penetrative. Current strategies for protecting electronics from radiation include adding redundant components, using error-tolerant code, switching to alternative radiation hardened components, or placing a radiation shield around sensitive devices. Adding a shielding layer may be the easiest to implement but increases weight and cost. Typically, radiation shields are made of toxic, high density, and high atomic weight materials, such as lead or depleted uranium. This research aims to find alternative materials that can be lightweight, inexpensive, amendable to rapid deposition processes, and effective at shielding against gamma radiation. Phy-X/PSD software was used to calculate the half value layer and linear attenuation coefficient of several materials at multiple gamma ray energies. The shielding capabilities of additively manufactured polylactic acid (PLA) and nylon, as well as commercial aluminum and lead sheets, were measured using a Geiger-Müller radiation counter when exposed to a cesium-137 and cobalt-60 source. To prevent the detector from counting beta rays emitted from the gamma sources, a PLA beta shield was created. The gamma attenuation of all the materials were tested both with and without the beta shield. The attenuation results better matched the calculations when using the beta shield.

Abstract ID: DESS2025-031

Additive Manufacturing of Inconel 718 and 316L ​Preforms for Forging Operations

Showmik Ahsan
Wright State University
VIgnesh Asam
Wright State University
Ahsan Mian
Wright State University
Daniel Young
Wright State University
Raghu Srinivasan
Wright State University

Laser Powder Bed Fusion (LPBF) additive manufacturing offers distinct advantages for producing components with intricate geometries and small batch sizes, making it particularly well-suited for aerospace applications that require high precision and material performance. This research investigates the utilization of LPBF to produce preforms of Inconel 718 and 316L stainless steel, which are subsequently subjected to forging and finishing operations. The study focuses on elucidating the influence of compressive deformation on the microstructural evolution and recrystallization behavior of additively manufactured IN718 and 316L alloys under varying temperature, strain, and strain-rate conditions. Preliminary results reveal notable heterogeneity in microstructure, mechanical response, and defect distribution. A comprehensive understanding of these factors is crucial for optimizing downstream thermomechanical processing and ensuring the microstructural integrity necessary for aerospace-grade components. Ultimately, this work aims to establish a more integrated framework between additive manufacturing and conventional metal forming to enhance the performance, reliability, and manufacturability of next-generation aerospace materials

Abstract ID: DESS2025-032

A Finite Element Approach to Understanding the Effect of 3D Printed Preform Shapes on Strain Distribution During Forging

Vignesh Asam
Wright State University
Showmik Ahsan
Wright State University
Raghavan Srinivasan
Wright State University
Daniel Young
Wright State University
Ahsan Mian
Wright State University

Additive manufacturing (AM) enables the near net shape production of preforms for hot forging eliminating the need for multiple intermediate dies. This study focuses on evaluating the properties, feasibility, and potential advantages of using additively manufactured (AM) preforms to reduce tooling requirements for low-volume forging applications. The focus of the study is on the design of AM-compatible preforms that promote uniform material flow and generate sufficient deformation on workpiece to enable recrystallization during forging. To achieve this, finite element analysis (FEA) using Simufact Forming software is employed to simulate the forging process and minimize reliance on experimental trial-and-error methods. Multiple preform geometries were developed and analyzed to investigate the influence of preform shape on strain distribution, as well as the effects of friction and temperature variations on the final forged part. The results provide insight into optimizing preform design for improved strain uniformity, forging efficiency, and microstructural changes for recrystallization, supporting the broader integration of AM technologies in metal forming applications.

Abstract ID: DESS2025-034

Design and Evaluation of Functional Inks for Precision Inkjet Printing in Heterogeneous Electronic Integration

Arashdeep Singh
Wright State University
Ahsan Mian
Wright State University

Abstract Inkjet printing is an efficient and scalable technique for fabricating flexible hybrid electronic devices, offering a platform for integrating advanced materials with precision manufacturing. This study focuses on the development, processing, and characterization of functional inks tailored for heterogeneous integration and sensor applications. Nano silver ink was used for its excellent electrical conductivity and ability to produce fine conductive patterns. For dielectric layers, polyimide and a polyimide/Ba₂TiO₃ nanocomposite were employed. The inclusion of barium titanate (Ba₂TiO₃) nanoparticles enhanced the dielectric constant, improving the overall performance of the printed electronics. The inks were formulated to ensure compatibility with the inkjet printing system and optimized for reliable deposition. After printing, the patterns were cured to solidify the materials and achieve desired mechanical and electrical properties. Characterization was carried out using Optical Microscopy for initial inspection of print quality, alignment, and pattern uniformity, Scanning Electron Microscopy (SEM) to assess surface morphology and pattern uniformity, while Energy Dispersive X-ray Spectroscopy (EDS) confirmed elemental composition and material distribution. This work demonstrates the potential of inkjet printing for producing high-resolution, functional structures using advanced conductive and dielectric materials. The integration of ceramic/polymer composites provides improved dielectric performance, making this approach highly suitable for next-generation applications such as flexible sensors, capacitors, and wearable electronics. Keywords: Inkjet Printing; Ag NP Ink; Barium Titanate; Polyimide; Flexible Electronics; Optical Microscopy; SEM; EDS

Aerospace Engineering

Abstract ID: DESS2025-022

Conceptual Analysis and Design of Ballistic Systems

Madison Sellers
Wright State University
Joy Trimbach
Wright State University
Mitch Wolff
Wright State University

This project reviews the conceptual analysis and design of ballistic systems. The objectives are to geometrically configure missiles in Engineering Sketch Pad (ESP), then use Conceptual Based Aerodynamics (CBAero) for the prediction of conceptual aerodynamic responses of the missile geometries at speeds ranging from Mach 4 to Mach 6, and finally to analyze these results to find how the lift and drag coefficients alter with altitude, Mach, and angle of attack.

Abstract ID: DESS2025-024

Development of an Aerospace Vehicle Conceptual Design Process using ADAPT Framework

Samuel Atchison
Air Force Institute of Technology
Matthew Madayag
Air Force Institute of Technology
Jose Camberos
Air Force Institute of Technology

The multidisciplinary challenges inherent to aerospace vehicle design and development result in a process that is both highly complex and deeply integrated. This increased integration requires analysis tools that can capture a broader range of physical phenomena for accurate evaluation. To meet this need, design frameworks allow the integration of analysis tools at selected (and variable) fidelity levels. One such design tool built specifically for aircraft design is the Aircraft Design, Analysis, Performance, and Tradespace (ADAPT) framework. This study describes the implementation of a design process for aerospace vehicles through the initial integration of the Engineering Sketch Pad (ESP), Configuration-Based Aerodynamics (CBAero), and Automatic Structural Layout Tool (AutoSaLT) as plugins within the ADAPT framework. We discuss the integration process of these tools in detail to show how we developed the plugins and linked them in ADAPT's workflow. We then show geometric, material, and structural layout trade studies on a selected geometry to showcase the capabilities of ADAPT, the potential of developing a design process within this framework, and to provide some insights from the trade study results. Distribution Statement A: Approved for Public Release; Distribution Unlimited. Public Release # 88ABW-2024-0904

Abstract ID: DESS2025-045

Flow Separation on Low-Pressure Turbine Blades Using Machine Learning – An Experimental Study

Aaron Suter
Wright State University

Awaiting public release.

Abstract ID: DESS2025-050

Development of Advanced Air Mobility Using Model-Based Systems Engineering

Vinay Kumar Reddy Sirigireddy
Wright State University
Darryl K.Ahner
Wright State University

Advanced Air Mobility (AAM) development represents a positive paradigm shift in metropolitan and regional areas, inspired by sustainable, efficient, and autonomous aerial technology. As AAM constitutes a complex cyber-physical system and Model-Based Systems Engineering (MBSE) approach offers powerful capabilities to analyze design trade-offs and optimize overall system performance. This research develops a System Modeling Language (SysML) enabled Model-Based Systems Engineering (MBSE) approach for the development of electric Vertical Takeoff and Landing (eVTOL) aircraft, focusing on system analysis and modeling specifically developing an architecture that employs the four pillars of SysML – Structure, Behavior, Requirements, and Parametric. Safe operations of eVTOL for Urban Air Mobility (UAM) routes in line with NASA and FAA’s NextGen Urban Air Mobility Concept of Operations (ConOps) version 2.0 is addressed in the architecture while applying a stringent examination of eVTOL applications with considerations of stakeholder requirements, Federal Aviation Administration (FAA) Regulations, and operational scenarios. A MBSE approach is applied to yield a methodical breakdown of eVTOL components is performed with MBSE to verify that all components adhere to safe, operational, and performance requirements. Moreover, the approach derives a systematic framework of airspace integrity and availability ideas, such as urban traffic management (UTM), real-time airspace monitoring, and flight corridors to perform safe operations. Ensuring formal verification and validation of eVTOL architecture while considering compliance with stakeholder requirements, AAM regulations, and operational constraints.

Abstract ID: DESS2025-051

Integrating Additive Manufacturing and Finite Element Analysis for Composite Materials Development and Architectures

Tahseen Al-wattar
Central State University
M.R. Hadizadeh
Central State University

This research introduces an integrated framework that advances the role of additive manufacturing from a prototyping tool to a powerful experimental platform for material innovation and model validation. The main idea lies in combining multi-platform 3D printing technologies, including fused deposition modeling (FDM), vat photopolymerization (VP), stereolithography (SLA), and powder-based methods with computational modeling such as Finite Element Analysis (FEA) and Artificial Neural Network (ANN) to both design and validate novel composite materials under realistic boundary conditions. This approach demonstrates that complex boundary and loading conditions typically confined to simulations can be physically realized through advanced 3D printing, enabling direct experimental validation. Initially, body centered cubic (BCC) lattice structures were designed using SolidWorks, 3D printed via fused deposition modeling (FDM) and experimentally tested under compression to validate FEM and artificial neural network (ANN) predictions. Building on this, hierarchical Inside BCC unit cells, combining cubic shells with internal lattices, were fabricated to study the effects of vertical and horizontal struts on mechanical responses, demonstrating strong correlation between experiments and FEA simulations. More recently, glass microfiber-reinforced high-temperature polymers were 3D-printed using vat photopolymerization (VP), with tensile testing and scanning electron microscopy confirming the influence of fiber content and post-curing on mechanical performance. Extend this framework to create composite material, which is polymer high temp resin, micropowder of boron nitride (BN), and milled glass fiber to explore as thermally conductive, electrically insulating interfaces for semiconductor devices. Across all phases, complex boundary and loading conditions traditionally applied in FEA models have been physically realized using advanced 3D manufacturing, enabling direct experimental validation. This integrated approach accelerates design cycles, enhances predictive accuracy, and demonstrates the versatility of advanced 3D manufacturing as a powerful research tool for fabricating and testing novel composite materials, bridging computational models with real-world applications. Keywords: Additive Manufacturing; Composite Materials; 3D Printing Technologies (FDM, VP, SLA, Metal, Nylon); Multi-Material Fabrication; Thermal Interface Materials (TIMs); Semiconductor Packaging This research was supported by the National Science Foundation under Grant Nos. NSF-OIA- 2430293 and NSF-EES-2436204, awarded to Central State University

Biomechanics / Biomedical Engineering

Abstract ID: DESS2025-019

Virtual Reality Motion Capture of the Upper Extremity using Machine Learning

Skyler Barclay
University of Dayton
Trent Brown, Allison L. Kinney, Timothy Reissman, Megan E. Reissman
University of Dayton
Tessa M. Hill, Ann Smith
Dayton Childrens Hospital

Virtual reality (VR) is increasingly popular in biomechanical research for its ability to present clear, customizable tasks. A majority of studies provide a variety of performance metrics, including spatiotemporal measures and pre- and post-intervention outcomes. However, the high cost and limited portability of traditional infrared (IR) motion capture systems limit their use in clinics that may want to adopt VR therapy and produce clinically relevant metrics while in the VR. Vive trackers offer a lower-cost, more portable option that can be integrated with VR therapy. While prior research has focused mainly on positional error of the trackers, few studies have examined joint angle accuracy. One exception reported root mean square errors (RMSE) as high as ±42°, raising concerns about clinical utility. To address this, our system uses IR motion capture to build a joint segment model and isolate tracker error independently from modeling discrepancies. The goal of this study was to characterize the error of two VR-based processing techniques, the VR skeletal model and a VR machine learning (ML) algorithm, relative to IR motion capture. Seventeen participants, including healthy controls and individuals with movement impairments (22 total data collections, aged 32.3 ± 13.5 years), completed this study. IR marker-based and VR tracker-based motion capture of the upper extremity were collected simultaneously while participants played customized levels in the VR game Beat Saber. Three techniques estimated joint kinematics (shoulder, elbow and wrist metrics): (1) IR skeletal modeling, considered the ground truth, calculated in Visual3D using traditional methods; (2) VR skeletal modeling which was defined by the IR markers and tracked using the VR markers; and (3) VR ML prediction, in which a bidirectional long short-term memory (BLSTM) algorithm predicted joint kinematics directly from raw VR motion capture. For the ML method, the first half of Beat Saber gameplay was used for training, while the second half was predicted and compared against the IR model to quantify error. Comparisons of range of motion (ROM) values between IR and VR skeletal models showed median errors below 3.5° ± 10.5°, with a consistent trend of overestimation by the VR skeletal model. In contrast, VR ML predictions achieved median errors below 1° ± 9°, with joint-specific variations around the true IR values. These findings indicate that while the VR skeletal model provides reasonable accuracy, the ML approach offers substantially reduced error and improved alignment with ground truth kinematics. The VR and IR skeletal model comparisons showed that the Vive trackers can accurately track body segments. The BLSTM results showed decreased error from the VR skeletal modelling. This means one baseline IR capture could make it possible for clinics to predict upper extremity joint kinematics of a patient during these customizable Beat Saber therapy games, and possibly other motions, with only the VR equipment, Brekel, and Python. Importantly, the diverse participant cohort suggests these methods are applicable across both healthy individuals and those with motor impairments, expanding the potential for clinical translation.

Abstract ID: DESS2025-021

Evaluating Ranges of Motion of VR Rehabilitation for Individuals with SCI

Andrew Hill
University of Dayton
Megan E. Reissman, Timothy Reissman, Allison Kinney
University of Dayton
Skyler Barclay, Trent Brown, Rebekah Revadelo
University of Dayton

Virtual reality (VR) offers an immersive and motivating environment for rehabilitation. Rhythm-based games like Beat Saber require dynamic upper-limb motions, making them promising for spinal cord injury (SCI) therapy. This study examined how different gameplay conditions influence range of motion (ROM) at the shoulder, elbow, and wrist. Seven participants with SCI (mean age 30.4±15.9 years) played custom Beat Saber levels designed from individualized high-ROM tasks. Three trial types were tested: Fast (speed-focused), K-Block (personalized optimal movements), and Paired (contrasting consecutive motions). Upper-limb kinematics were tracked using a 10-camera infrared motion capture system, and repeated measures ANOVA assessed ROM differences. Results showed significant effects of trial type for shoulder and elbow ROM. Fast produced the lowest ROM, K-Block intermediate, and Paired the highest. Shoulder abduction/adduction averaged 23.4°, 26.1°, and 29.7° across conditions, while elbow flexion/extension averaged 35.6°, 38.8°, and 41.4°, with all differences significant. Paired movements elicited larger motions due to compounded, sweeping actions. Fast reduced ROM at the shoulder and elbow but did not increase wrist ROM as hypothesized, suggesting alternative kinematic strategies. These findings indicate that task presentation strongly influences kinematic behavior in SCI rehabilitation. Paired movements may be especially effective for promoting ROM expansion, while Fast tasks could support performance training. Personalized VR rehabilitation using Beat Saber demonstrates potential as a customizable and engaging tool to enhance functional recovery in SCI populations.

Abstract ID: DESS2025-025

Impact Of Arm Dominance and Practice Type on Movement Task Performance Post Spinal Cord Injury

Rebekah Revadelo
University of Dayton
Skyler Barclay, Andrew Hill, Trent Brown
University of Dayton
Allison Kinney, Timothy Reissman, Megan E. Reissman
University of Dayton

  Task-specific training is a key strategy in rehabilitation following spinal cord injury (SCI), particularly for restoring upper extremity function that supports independence and mobility. Virtual reality (VR) provides a unique platform for delivering controlled and engaging rehabilitation tasks. This study investigated how practice structure—blocked versus random—and arm dominance affect motor task performance in individuals with SCI. Seven participants with SCI (5 males, mean age 30.4 ± 15.9 years, 4 cervical and 3 thoracic injuries, average 12.4 ± 8.2 years post-injury) completed VR-based movement tasks using Beat Saber. Participants cut through blocks in specified directions timed to music beats, completing four sequential trials: blocked (BLOCK 1), two random (RAND 1, RAND 2), and a final blocked trial (BLOCK 2). Dominant (DOM) and non-dominant (NON) limb performance was compared. Performance was assessed via Cut Offset Error (distance from block center) and Cut Angle Error (accuracy of cut direction). Results showed that arm dominance significantly influenced performance. The NON side demonstrated greater initial error in both metrics but improved across trials, with significant reductions in Cut Angle Error from BLOCK 1 to BLOCK 2. In contrast, DOM-side performance remained stable across conditions. Trial type also affected accuracy, with BLOCK 2 outperforming RAND 1. These results suggest that improvements were driven by the NON side, which had more capacity for change, while the DOM side maintained consistent accuracy. These findings demonstrate that short-term VR-based training can improve nondominant limb performance, reducing asymmetry between limbs. Given the importance of balanced upper extremity use for daily independence in SCI populations, VR practice protocols that emphasize nondominant limb training and incorporate task variability may offer effective rehabilitation strategies.

Abstract ID: DESS2025-029

Sources of Variability in Intracranial Aneurysm Model Reconstruction and Evaluation: A Systematic Investigation

Jared Chong
Wright State University
Hang Yi
Oklahoma State University
Alexander E. Wang
Centerville High School
Cindy Ju
Upper Arlington High School
Zifeng Yang
Wright State University

The reliability of intracranial aneurysm (IA) models is critical for pathophysiology diagnosis and computational simulations. This study aimed to quantify the impact of segmentation threshold and software platform on the reconstruction of IA model geometry as well as the impact of inter-user variability on the evaluation of IA models. A total of 600 IA models were reconstructed from 100 patient DSA datasets using Materialise Mimics and 3DSlicer at three grey value (GV) threshold levels; 1000, 1500, and 2500. Geometric measurements were performed in 3-matic by three users (R1, R2, and R3) with varying experience levels. Measurements included vessel diameters and aneurysm morphology parameters. Mimics, the 2500 GV threshold, and the most experienced user, R1, served as a baseline for comparison. Normality was evaluated using Shapiro-Wilk tests, and statistical differences were assessed with paired t-tests and relative percent differences. All anatomical regions showed statistically significant geometric variation across software and threshold. Model evaluation showed potential statistically significant variation between users. Models from 3DSlicer were consistently smaller than those from Mimics with percent differences ranging from −1.27% to −4.38% (all p < .05). Lower thresholds produced consistently larger models; decreasing from 2500 GV to 1000 GV increased average diameters by up to 15.9%, depending on specific region (p < .05 for all comparisons). User-related variability was most pronounced in the least experienced user, R3, with size measurements deviating by up to 22.67% from R1 (p = 2.36E-17), while R2’s measurements showed minimal differences. Segmentation software, threshold selection, and user interaction each introduce meaningful and statistically significant variability into IA model geometry and evaluation. Standardization of segmentation protocols—especially threshold values and operator training—is essential to improve reproducibility. These findings highlight the importance of transparent and validated workflows for clinical and research applications reliant on IA reconstructions.

Abstract ID: DESS2025-033

Smart Rollator Walker Attachment with Haptic Feedback

Sarah Boeckman
University of Dayton
Timothy Reissman
University of Dayton

Many rollator walker users do not receive proper training and often feel uncomfortable or unsafe using their device, which can lead to poor posture, instability, and increased risk of falls. This project focuses on developing a haptic feedback system that provides real-time guidance to help users maintain safer walker technique during everyday use. Proper rollator use typically involves a neutral trunk posture, a 15–20° elbow bend, and foot placement within the frame of the walker. The proposed system uses non-contact distance sensors to monitor these factors and delivers vibration feedback to the handles when the user is outside the recommended range. The device attaches to a standard rollator, requires only a one-time setup, and enters a low-power sleep mode when not in use to prolong battery life. It also records basic positioning data that can be shared with a clinician for training feedback if desired. Current efforts are to refine the system and test for durability. Future work will entail human subject testing to evaluate whether it can improve safety and reduce fall risk during walker use.

Abstract ID: DESS2025-039

Ankle Exoskeletons: Increasing Degrees of Freedom via Design of a Passive System

Lucille Baier
University of Dayton
Timothy Reissman
University of Dayton

Exoskeletons are mechanisms that attach to parts of the body to aid in a person’s mobility, stability, and overall energy. The ability for an ankle exoskeleton to fully allow for the multi-axial movements of the ankle is important for its ability to rehabilitate and strengthen the user’s ankle in a safe manner. These degrees of freedom are crucial in the improvement of clinical and everyday use of ankle exoskeletons. The purpose of this research was to modify a single-degree-of-freedom, commercial ankle exoskeleton (Humotech Caplex EXO-001) in order to increase the range of motion in other axes. This was done through the exploration of eight possible designs using a 3D modeling program. The final design consisted of a set of spherical joints near the ankle and a set of pivot joints at the toe. This final design was then 3D printed using Onyx material (Markforged X7 system) and compared to the original carbon fiber Humotech design using benchtop testing without a user. The range of motion for the existing degree of freedom (dorsiflexion and plantar flexion) was retained, while additional degrees of freedom increased. In particular, abduction and adduction increased from 0 to 20 degrees. Additionally, inversion and eversion increased from 0 to 5 degrees. These results showed these passive mechanisms achieved a better multi-axial range of motion for the device, more commensurate with expected degrees of freedom experienced at the ankle while walking. Further research is necessary in order to test the device’s range of motion with a user while walking to confirm its translational utility.

Controls

Abstract ID: DESS2025-030

Safe Navigation in the Presence of Range-Limited Pursuers

Thomas Chapman
Air Force Research Laboratory
Alexander Von Moll
Air Force Research Laboratory
Isaac E. Weintraub
Air Force Research Laboratory

This paper examines the degree to which an evader seeking a safe and efficient path to a target location can benefit from increasing levels of knowledge regarding one or more range- limited pursuers seeking to intercept it. Unlike previous work, this research considers the time of flight of the pursuers actively attempting interception. It is shown that additional knowledge allows the evader to safely steer closer to the threats, shortening paths without accepting additional risk of capture. A control heuristic is presented, suitable for real time implementation, which capitalizes on all knowledge available to the evader. Distribution Statement A. Approved for public release. Distribution is unlimited. PA#: AFRL-2025-4392

Design & Optimization

Abstract ID: DESS2025-014

Novel High-Speed Mechanical Press Designs Optimized for Improved Ram Dwell Limited by Joint Force Considerations

Tianze Xu
University of Dayton
Andrew P. Murray
University of Dayton
David H. Myszka
University of Dayton

A mechanical press shapes parts by driving a ram into a metal sheet to deform it into a desired form. Because this process is widely used—from forming pop cans to shaping car body panels—mechanical presses play a crucial role in global manufacturing. The metal forming industry has recently encountered a shift towards servomotor drivetrains that can electronically alter the ram motion profile. The objective of this research is to develop alternative linkage drivetrain designs that generate prescribed ram motions while maintaining acceptable joint forces. By focusing on a drivetrain linkage, this study leverages the advantages over their servo-driven counterparts, including higher speeds, lower costs, greater precision, and improved energy efficiency. The research evaluates five drivetrain designs under industrial conditions to enhance the dwell phase and achieve the required joint forces. Two of these designs are currently prevalent in the industry, while the remaining three offer potential advancements.

Abstract ID: DESS2025-018

Structural Design Optimization of a Bio-Inspired Aircraft with a Rotating Empennage

William Stone
University of Dayton
David Myszka
University of Dayton
Andrew Murray
University of Dayton
Rick Graves
Air Force Research Laboratory

This presentation explores structural design optimization for an aircraft, motivated by bird flight. The concept aircraft eliminates the vertical stabilizer and incorporates a rotating empennage to maintain control during agile maneuvers. The proposed bio-inspired rotating empennage (BIRE) provides three degrees of freedom: independent rotation of each horizontal stabilizer and rotation of the entire empennage relative to the fuselage. This configuration offers potential benefits of reduced drag and weight, thereby improving efficiency. From a structural standpoint, the empennage must be especially lightweight and rigid to minimize inertial effects during rotation. To address this, topology optimization was applied to the BIRE frame, followed by shape optimizations in critical regions to ensure manufacturability and structural performance. Results of these optimization studies will be presented, highlighting the trade-offs between efficiency, strength, and feasibility in bio-inspired aircraft design.

Abstract ID: DESS2025-046

Passive Flow Control Optimization for Low-Pressure Turbine Performance

Bryant Burton
Wright State University

Awaiting public release.

Engineering Education

Abstract ID: DESS2025-012

A Systems Engineering Framework for Internationalizing Engineering Education

Sharon Bommer
University of Dayton

Engineering graduates must be prepared to work in globally distributed, multicultural teams. Collaborative Online International Learning (COIL) offers a scalable way to internationalize engineering curricula by embedding cross-border collaboration without the barriers of traditional study abroad. This study presents a COIL module co-developed between the University of Dayton (USA) and the University of Lagos (Nigeria). Using a systems engineering framework, the module was integrated into existing courses, addressing design, implementation challenges, and solutions. Program impact was evaluated through a validated measure of intercultural competence, demonstrating COIL’s potential to strengthen global competence in engineering education.

Fluid Dynamics / CFD

Abstract ID: DESS2025-002

On the A Priori Calculation of Coefficients for Practical Tensor Basis Turbulence Models

James Wnek
Wright State University
Mitch Wolff
Wright State University
Eric Wolf
Ohio Aerospace Institute
Christopher Schrock
Air Force Research Laboratory

Tensor basis neural networks (TBNN) and their variants are a major class of machine learning-based turbulence models that predict the coefficients of Pope’s tensor basis expansion of the Reynolds stress. To improve robustness and efficiency, it is desirable to use the fewest, lowest-order terms necessary. For practical models, these coefficient fields should be smooth and sparse with a maximal non-negative eddy viscosity. The current literature on the optimal number of basis tensors does not simultaneously account for all these properties, thus leaving a gap in their application to real models. Here, we propose a modified, alignment-weighted regularization scheme to calculate the tensor basis coefficients with the desired properties. Sample calculations are provided for fully developed square duct flow that validate the methodology. The results of this research can be used for both investigating the optimal number of basis tensors and pre-computing tensor basis coefficients for TBNN models. Distribution Statement A: Approved for Public Release; Distribution is Unlimited. PA# AFRL-2025-4996

Abstract ID: DESS2025-013

Modified Turbulence Model Implementation into OpenFOAM

Lincoln Dehaven
Wright State University
James Wnek
Wright State University
Mitch Wolff
Wright State University
Christopher Schrock
Air Force Research Laboratory

Turbulence modeling in computational fluid dynamics of the Reynolds-Averaged Navier Stokes Equations (RANS) requires addressing the Reynolds Stress terms and the closure problem associated with the six new terms introduced. The closure problem requires additional equations be provided for a solution to be obtained. The additional equations while rooted in known physical values struggle with the capturing of complex flow physics. This work seeks to verify the RANS Spalart-Allmaras noft2 Quadratic Constitutive Relation 2000 version (SA-noft2-QCR2000) using OpenFOAM. OpenFOAM was used to run the normal Spalart-Allmaras noft2 (SA-noft2) model and the SA-noft2-QCR for two cases available in the Langley Research Center Turbulence Modeling Resource. The two cases used are the 2D Zero Pressure Gradient Flat Plate (2DZP) and the 3D Supersonic Square Duct (3DSSD). OpenFOAM’s SA model matches the provided non dimensional viscosity published from NASA. The SA-noft2-QCR2000 model also matches for the viscosity at x=0.97. The verification of SA-noft2-QCR2000 in OpenFOAM provides a road map on how to make the changes in the turbulence model as big data methods will be explored. PA#AFRL-2025-5001

Abstract ID: DESS2025-015

Wall-Street – A Gambler’s Paradise? Can Principles of ‘Turbulence’ Help/Disrupt Wall-Street Trading?

B. G. Shiva Prasad
Fluid Thermal Technologies

‘Turbulence’ - a commonly used English word has universal application in all branches of science and engineering. Share price fluctuations in Wall-street stock or other similar markets are very good examples of turbulent events/phenomena. Just as in many other cases, such fluctuations cannot be attributed to one or two or even, a few factors/parameters. To understand any turbulent phenomenon or in other words the mechanism/s governing such phenomenon, one will have to identify the dominant parameter/s defining/controlling such systems. Hence even on a gross scale, correlating the major wall-street indices like Dow Jones Industrial Average, Nasdaq, S & P 500, etc. with a few age old dominant factors/parameters like GDP, inflation, interest rate, unemployment index, etc. tends to become obsolete due to societal change, growth and advancement. One should note here that Turbulence in Wall-street (Wall Street Dynamics) is influenced by millions of human beings, each one’s behavior itself is turbulent and virtually unpredictable! Similarly over a smaller scale, to a lay person, predicting the behavior of any sector or a mutual fund or the share price fluctuation of any particular corporation or industry is extremely difficult due to the number of factors determining such fluctuations. Hence, Wall-street has become a gambler’s paradise (Shiva Prasad, 2012 & 2023). This is harmful to the society, as unfortunately, the Wall-street share price variation or growth is normally used to assess the product or service offered by a company, although it need not necessarily have any bearing/correlation with the quality and reliability of the product or service. This paper tries to demonstrate how a wall street trader (gambler?) or a stock or fund manager involved in internet and high frequency / programed trading can try to make money most of the times at least, by using the principles of turbulence and digital sampling, and thus disrupt the notion that wall street is a “gambler’s paradise”. The reason why it can disrupt Wall-street trading is because, if every trader starts using this technique and is always winning, there will be no losers and stock trading will no longer involve any gambling. The question being, how does a trader/manager know when to bid on a particular stock and be certain that his/her bid will win? This is where application of the knowledge of turbulence, signal processing & analysis or in general – engineering knowledge could help. In internet trading, one could always start buying only when the share price is increasing and start trading at a frequency much faster (at least 5 times – the higher this number, the better it is) than the observed highest frequency (considering both increasing and decreasing parts of the signal) and continue to buy until the share price starts (inflexion point) to decrease and then immediately sell all of the money accumulated. One could compute and even monitor the slope of the highest frequency content in the share price fluctuation signal and its derivative and use them to guide when to buy and sell their shares.

Abstract ID: DESS2025-040

Effects of As-Manufactured Geometry on Performance

Patrick Martens
Wright State University

Awaiting public release.

Abstract ID: DESS2025-047

Analyzing the Resilience of the Law of the Wall in Turbulent Flows under Transpiration

Christian Caldwell
Wright State University
George Huang
Wright State University

Transpiration alters the structure of near-wall turbulence and challenges the classical scaling laws of the Law of the Wall. Using direct numerical simulation data for turbulent Couette and Poiseuille flows with uniform wall-normal blowing and suction, a velocity transformation has been developed that collapses mean-velocity profiles of different transpiration rates onto the canonical log-law slope defined by the von Kármán constant. This result indicates a partial preservation of similarity in the near-wall region under transpiration. Work is ongoing to establish the corresponding wall-normal coordinate transformation needed to recover the universal intercept constant of the log law. Existing turbulence models are being evaluated to assess their performance under transpiration and to identify limitations in predicting modified near-wall dynamics. Building on these insights, future efforts will focus on developing a new transpiration-aware turbulence closure that incorporates wall-normal mass flux effects.

Abstract ID: DESS2025-049

Void Fraction Analysis of Two-Phase Flow

Liam Hackett
Wright State University

Awaiting public release.

Heat Transfer / Thermal Sciences

Abstract ID: DESS2025-004

Observation of Trans-critical and Supercritical CO2 under G-Forces

Evan Fender
University of Dayton Research Institute
Jerod McCoppin
University of Dayton Research Institute
Justin DelMar
Air Force Research Laboratory

Supercritical carbon dioxide (sCO₂) has gained significant attention in recent years due to its abundance, favorable thermophysical properties, and potential for use in advanced power generation and thermal management systems. However, its high critical pressure and complex behavior near the critical point pose substantial experimental challenges. This work presents the design and development of a high-pressure visualization chamber for observing density variations in sCO₂ using Schlieren imaging. When integrated into a closed-loop sCO₂ system mounted on a G-table, this setup enables the investigation of density gradients and flow phenomena under varying g-force conditions. The results aim to improve understanding of supercritical fluid behavior in dynamic environments relevant to aerospace and energy applications.

Abstract ID: DESS2025-007

Conformal Heat Exchanger Analysis for Aerospace Applications

Nathan Lewan
Wright State University

The rapid evolution of aerospace technology has introduced a growing demand for efficient thermal management systems, particularly in military aircraft and unmanned aerial systems. Heat exchangers play a pivotal role in dissipating excess heat generated by advanced avionics, propulsion systems, and high-power payloads. Conventional heat exchangers, while effective, present limitations in terms of weight, size, and susceptibility to mechanical failure. Recent advances in manufacturing techniques, such as additive manufacturing, have opened new possibilities for designing and producing heat exchangers with complex geometries that traditional manufacturing methods could not achieve. A particularly promising approach involves the use of Triply Periodic Minimal Surfaces, which offer enhanced surface area-to-volume ratios and improved thermal transfer efficiency. This work aims to experimentally and computationally evaluate additively manufactured heat exchangers with the TPMS structure for their heat transfer efficiency, pressure drop, and overall feasibility. The results of this work will enhance the overall understanding of how these novel heat exchangers perform compared to their traditional counterparts and if the technology is ready for implementation into advanced air platforms. Distribution Statement A. Approved for public release: distribution is unlimited. PA#: AFRL-2025-2401

Abstract ID: DESS2025-009

Thermal Characterization of Thin Film/Coating from Nanoscale to Bulk Materials

Yanan Yue
Miami University

Thin films and coatings play a critical role in industrial equipment, serving functions such as corrosion protection and thermal insulation. Their thickness spans from the nanometer to the microscale, and in some cases, bulk dimensions. Characterizing their thermal properties and structures is both essential and challenging, largely due to limitations in current instrumentation. In this presentation, I will highlight recent advances from my lab aimed at overcoming these challenges in thermal characterization of thin films and coatings. Specific examples include Raman-based analysis of 2D materials to probe in-plane and interfacial thermal resistance, frequency-domain photothermal techniques for through-thickness thermal conductivity measurement, and a self-developed portable instrument designed for onsite evaluation of coating thermal properties.

Other

Abstract ID: DESS2025-037

Pressure limitations based on wall thickness of a TPMS lattice structure

Kathleen Spangler
Air Force Institute of Technology

Awaiting public release.

Renewable and Clean Energy

Abstract ID: DESS2025-011

Experimental Validation of Solar Panel Tilt Optimization and Microclimate Variations of Solar Prairies

Alexander Zawacki
University of Dayton
Rydge Mulford
University of Dayton
Owen Koscho
University of Dayton

Awaiting public release.

Structures / Solid Mechanics

Abstract ID: DESS2025-016

Material Response of Inconel 718 for High Strain Rates via Taylor Impact Testing

Katie Bruggeman
Wright State University
Anthony Palazotto
Air Force Institute of Technology
Daniel Young
Wright State University

Inconel 718 (IN718) is a nickel-based super alloy which is often utilized for aerospace applications through both traditional and additive manufacturing methods. The characteristics of wrought and Additively Manufactured (AM) IN718 are currently being investigated and compared after the material is exposed to a high strain rate impact with a rigid target. High energy impact creates viscoplastic strains and failure, which can be detrimental to the performance of the material when considered for various applications. Wrought IN718 bar stock purchased from McMaster-Carr® is used to create specimens for impact testing. Each specimen is further characterized by a length of 2 inches and a diameter of 0.5 inches. Testing performed by McMaster-Carr® indicates that the wrought IN718 contains 53.88% of Nickel, 18.65% of Iron, 17.70% of Chromium, and 9.77% of other elements. Specimens are also created via additive manufacturing processing by utilizing an Open Additive PANDA printer. The experiment was carried out via Taylor Test experimental approach. A Taylor Impact Test, which is a well-known high velocity test, is performed physically at the Air Force Institute of Technology (AFIT). The specimens are fired toward a rigid steel target via a single-stage gas gun which utilizes Nitrogen gas as a pressure source. For this study, various pressures between 300 and 600 psi are measured at the gun. The travel distance of the specimens totals 53 inches, including length of the barrel and free space. During experimental impact testing, it is required to calculate the velocity of the projectiles through a photographical technique referred to as Cross-Image Correlation. This technique allows the velocity to be calculated by measuring the distance traveled by the specimens over time; the correlation of multiple image frames determining the distance traveled. The camera and software package utilized for velocity measurement at AFIT is Phantom V12.1 and PCC 3.9, respectively. PCC 3.9 captures a video of the impact and performs data analysis. The experimental process begins with inserting a standard 1-foot ruler into the ballistic test section where the projectile hits the test article. The number of pixels given the choice of a preselected resolution is defined over a measured region. During calibration, the number of pixels with the given distance of 3 inches (based on the ruler) is found and converted to ft/pixel. Dimensionalities described by Taylor for an impact scenario include the total length of the specimen before deformation as L, the total length of the specimen after deformation as L1, the region within the specimen that does not experience plastic deformation after impact with the rigid target as X, and the diameter of the end of the specimen after impact as D. Current analysis shows wrought and AM IN718 following similar trends when subject to high strain rates and varying velocities. Although, AM materials experience more deformation than wrought material. Wrought material may be more suited for high impact scenarios compared to their AM counterparts. Future work may include heat treatment of the AM specimens as well as changing the process parameters utilized for additive manufacturing.

Abstract ID: DESS2025-023

Finite Element Analysis of Triply Periodic Minimal Surface Gyroid Structures in Combined Loading

Tanner Barber
Air Force Institute of Technology
John Brewer
Air Force Institute of Technology

Awaiting public release.

Abstract ID: DESS2025-027

Dynamic response of cylindrical specimens subjected to high-velocity impact against a rigid target

Armando Deleon
Wright State University
Anthony N. Palazotto
Wright State University
Katie Sue Bruggeman
Wright State University

Dynamic Impact Testing of Inconel 718: Taylor Test Analysis This research examines the high-velocity impact behavior of Inconel 718 (IN718) cylindrical specimens using Taylor test methodologies, integrating experimental testing, analytical modeling, and finite element simulations to characterize the material's viscoplastic response under extreme conditions. Experimental Approach Cylindrical IN718 specimens were launched using a single-stage nitrogen gas gun (bore diameter: 0.0127 m, barrel length: 3.048 m) at controlled velocities toward a rigid anvil. High-speed video imaging captured the deformation process, enabling precise measurement of final length, mushroomed diameter, and deformation profiles. The experiments revealed significant strain localization and work hardening, demonstrating that viscoplastic effects are essential for accurately modeling impact events—purely elastic or rigid-plastic models proved inadequate. Analytical Framework Dynamic Taylor equations were developed to describe momentum and energy conservation during impact. These equations estimated initial and residual velocities and quantified energy dissipated through plastic deformation. Analytical predictions were validated against experimental data to assess the Taylor model's accuracy in predicting post-impact specimen geometry. Numerical Simulation A finite element model was constructed in ABAQUS/Explicit using the Johnson-Cook plasticity model, which incorporates strain hardening, strain rate sensitivity, and thermal softening. The model consisted of 307,165 elements and 320,624 nodes. Johnson-Cook parameters for wrought IN718 were: A=1200 MPa, B=1284 MPa, C=0.006, n=0.54, m=1.2, with T_m=1588 K and T_0=300 K. Simulation results showed excellent agreement with experimental measurements at multiple impact velocities (133.59 m/s and 185.28 m/s). The model successfully captured strain rate-dependent behavior, with predicted deformed length matching within 2.6-13.5% of experimental values. Critically, the finite element analysis confirmed Taylor's fundamental assumption that particle velocity in the deformation region approaches zero during impact. Key Findings The research provides several important insights: viscoplastic effects are critical for accurate impact modeling; the Johnson-Cook model effectively simulates high-velocity deformation of IN718; and the integrated approach successfully validates both experimental and analytical methodologies. The convergence between experimental measurements, analytical predictions, and numerical simulations provides confidence in using these methods for predicting material behavior under similar impact conditions. Future Directions Future work will extend testing to higher velocity ranges to explore deformation mechanisms at elevated strain rates beyond current laboratory capabilities. Additionally, incorporating damage and failure criteria into constitutive models will enhance predictive capabilities, supporting development of resilient materials for aerospace, defense, and energy applications where high-rate impact resistance is critical.

Undergraduate Research Projects

Abstract ID: DESS2025-005

Quality Estimation from Void Fraction via the Drift Flux Model

Colin Fokine
Wright State University

Accurate quality prediction in two-phase flow is critical for the stability and efficiency of thermal management systems. Most modeling approaches estimate void fraction from known quality. In contrast, this study investigates the derivation and application of the drift flux model to derive quality measurements from void fraction in a two-phase R-134a system. The Drift Flux Model incorporates the relative motion between the liquid and vapor phases through a drift velocity term and a drift flux coefficient, providing a better representation of dynamics at the interface. This key difference allows the drift flux model to capture system behavior with higher fidelity under both transient and steady-state conditions. An electrical capacitance tomography (ECT) sensor provided real-time void fraction data in a two-phase R-134a system. These measurements were used to estimate quality. The estimated quality was then validated using the energy balance equation and the separated flow model. Distribution Statement A. Approved for public release: distribution is unlimited. PA#: AFRL-2025-4604

Abstract ID: DESS2025-028

Liquid Metal Conductors for Wearable Strain Sensors

James Weaver
University of Dayton
Alex Watson
University of Dayton
Josefat Jimenez
University of Dayton
Ashok Rathanlal
University of Dayton

Accurate and consistent measurement of joint angles is essential across fields ranging from physical therapy to sports science and motion capture. However, most existing systems are bulky, expensive, or inaccurate. This project explores the potential use of liquid metal strain sensors as a lightweight, flexible alternative for tracking body positioning. The sensors were fabricated using conductive liquid metal ink comprised of Eutectic Gallium Indium (EGaIn) patterned on thermoplastic polyurethane (TPU) substrates. When stretched, the ink’s resistance changes proportionally to strain, allowing estimation of joint angles based on calibrated resistance–angle relationships. Over 35 sensor prototypes were tested with variations in trace geometry, substrate thickness, and attachment method to optimize performance. The most accurate prototypes achieved an average error of 3.43% across angles from 0 to 135°, with peak accuracy reaching 0.28% error at higher flexion angles. These results demonstrate strong short-term accuracy and repeatability immediately following calibration. However, long-term use revealed substantial drift in readings due to plastic deformation of the TPU substrate, limiting reliability over extended use. Continued research aims to identify more elastic materials and integrate predictive algorithms to mitigate drift and recalibration requirements. This presentation will discuss the design iterations, testing methods, and key challenges encountered in developing a wearable, flexible angle sensor, as well as insights into how material behavior fundamentally affects the reliability of soft sensing technologies.

Abstract ID: DESS2025-036

Spatiotemporal Analysis of Turbulent Free Jets Using 100-kHz, 2D Particle Image Velocimetry

Madelyn Torrans
Cedarville University
Seth Mitchell
Cedarville University
Joseph Miller
Cedarville University

Understanding turbulent flow development and the dynamics of turbulent eddies in highly sheared free jets is applicable to many important aerospace challenges including jet noise from military and commercial air vehicles, surface cooling, and jet mixing. Computational fluid dynamics simulations and simple correlation methods are commonly used to study turbulent flow, but it is necessary to validate these results. In this work, turbulent flow velocity data collected using high-speed, two-dimensional particle image velocimetry is used to compare the prediction accuracy of Taylor’s Frozen Flow hypothesis to the Elliptic Approximation model. While spatiotemporal correlations and Elliptic Approximation models have been used previously to study turbulent flows, the use of highly accurate, experimentally collected data in the validation process is unique. Data was collected using a high-speed laser system to capture particle velocity with a spatial resolution of 0.54 mm within the free jet with temporal resolution of 10 μs and total record length of 100 ms. Reynolds number was varied between 21,000 and 78,000 by increasing jet velocity. Two-dimensional space-time correlations are computed and analyzed as a function of radial and axial location in the free jets.

Abstract ID: DESS2025-044

Hybrid UAV Energy Management

Ryan Finney
Wright State University
Annie Hagan
Wright State University
Mitchell Hughes
Wright State University
William Breuninger
Wright State University

Unmanned Aerial Vehicles have had increasing use in the military and have begun to be used in the private sector. An issue with small-scale UAVs is limited battery technologies; flight time and payload are limited. This research aims to develop an autonomous energy management platform for a hybrid quadcopter UAV that uses a mounted internal combustion engine as a backup energy source. The ICE does not power the quadcopter motors directly; instead, the ICE is coupled with a brushless DC motor that serves as both a DC generator when being driven by the ICE and a motor starter for the ICE when supplied with DC energy from the batteries. The current focus of the project is refining the control system to be able to autonomously start the ICE when the battery level is low and to enable the programming of different missions. There is no flying prototype; rather, the control architecture is implemented with a simulated test stand that uses two identical 48V DC motors, with one acting as the generator/starter and the other functioning as the ICE using an AC/DC converter to power the ICE. Only a single motor is used as the flight load, which is powered by the battery pack, a 6s configuration of 3.3V LiFePo4 cells. The closed-loop control is executed using Python code on a Raspberry Pi 4B. In tandem, a digital model is also being developed in Simulink to compare results with the test bench.

Poster Presentations

Additive Manufacturing

Abstract ID: DESS2025-026

Improvement of Mechanical and Electrical Properties of Additively Manufactured PDMS-Graphene Composites for Wearable Devices

Braden Cowger
Miami University
Muhammad P. Jahan
Miami University

Polydimethylsiloxane (PDMS) is a biocompatible material that can be additively manufactured using direct ink writing (DIW), enabling the creation of custom and complex geometries. Graphene nano-powder (GRNP) is a filler material with high tensile strength and excellent electrical conductivity, which can be mixed into PDMS to create electrically conductive wearable devices. This study explores the use of GRNP for the improvement of mechanical properties of PDMS while introducing electrical conductivity. The PDMS-GRNP composite is fabricated by creating a specialized ink suitable for DIW. The study analyzes the effects of composite formulations on printability, tensile strength, and electrical resistance properties of PDMS-GRNP composites. These properties are characterized using tensile testing, rheological analysis and dynamic mechanical analysis (DMA). The addition of the GRNP in the PDMS matrix creates a flexible piezo resistor that can measure stress and strain. However, the study demonstrates that the addition of too much filler material will cause the sample to become brittle and resistant to deformation. The composite displays repeatable piezoresistive properties, with resistance tracked using a strain gauge like geometry under cyclic extension. Finding a balance between electrical conductivity and mechanical properties is critical for the implementation of the PDMS wearable devices. Two different types of graphene powders were analyzed in this study: GRNP for electrical and thermal conductivity, and functionalized GRNP for mechanical reinforcement. The addition of 2 wt.% functionalized GRNP demonstrated an increase to the maximum tensile strength and maintained the flexibility and extension capabilities of the pure PDMS. The addition of a small amount of GRNP for electrical conductivity has shown to make the composite a promising candidate for wearable electronics with increased mechanical properties. The PDMS composites have potential applications in aerospace structural monitoring, soft robotics, human health monitoring, motion capture, and haptic devices. This research contributes valuable insights into optimizing PDMS-GRNP composites for wearable devices applications.

Abstract ID: DESS2025-043

Optimization of Droplet Formation Parameters in Material Jetting with MicroFab JetLab® 4XL

Meenamrutha Meghana Attaluri
Wright State University
Meenamrutha Meghana Attaluri
Wright State University
Arashdeep Singh
Wright State University
Ahsan Mian
Wright State University

Additive manufacturing (AM) is transforming how materials are fabricated layer by layer. Among various AM techniques, material jetting (MJ) stands out for electronic micro-fabrication due to its precision and flexibility. In MJ based inkjet printing (IJ), a non-contact technique, microdroplets are ejected from a printhead without touching the substrate. The MicroFab JetLab® 4XL system exemplifies high-precision material jetting, offering fine control over droplet formation through critical parameters such as voltage and pulse timing. Voltage governs the ejection velocity, while timing influences droplet size and stability. Tailoring these parameters enables precise control over droplet behavior, ensuring uniform and stable deposition. Waveform shape significantly affects droplet dynamics: standard square waves generate small droplets; sine waves produce larger ones, and complex multi-waveforms are capable of ejecting ultra-fine droplets. These variations make the system highly versatile for research applications, especially in printed electronics and biomedical materials. This study highlights how waveform parameters must be optimized for each material. For instance, Titanium dioxide (TiO₂) requires higher voltages and longer pulse durations to form uniform droplets and consistent lines. In contrast, materials like silver (Ag) and lithium nickel oxide (LiNiO) perform best with shorter, uniform pulses for stable ejection and precise patterning. Thus, each material demands a custom waveform profile to achieve optimal printing performance

Abstract ID: DESS2025-035

Mechanical Behavior of 3D-Printed Glass Microfiber Reinforced Polyamide (PA-12) Composites Created at Different Build Orientations

Jeet Thapa
Wright State University
Adedamola Adeyemi
Wright State University
Jeet Thapa
Wright State University
Toufik Kanit
Wright State University
Ahsan Mian
Wright State University

Polyamide-12 (PA-12) reinforced with glass microfibers (GMF) is gaining interest due to its high strength, lightweight, and compatibility with powder bed fusion (PBF) additive manufacturing (AM) technology. The AM-processed GMF/PA-12 composite parts often exhibit variations in mechanical behavior depending on their build orientation during fabrication. This study focuses specifically on the effect of build orientation on the stress–strain response and failure behavior of 3D-printed PA-12/GMF composites. Standard ASTM D638 Type 4 tensile samples were fabricated using the Formlabs Fuse 1 selective laser sintering (SLS) printer in multiple orientations. The printed specimens were subjected to tensile testing to determine key mechanical properties such as modulus, yield strength, and fracture strain. In addition, samples were exposed to different environmental conditions (e.g., temperature and moisture) to understand their effects on mechanical properties. Preliminary observations suggest that build orientation and environmental conditions influence stiffness, strength, and failure behavior, with certain orientations promoting higher load-bearing capacity and improved surface integrity. Keywords: Additive Manufacturing, composite materials, glass microfiber, polyamide, environmental effects

Abstract ID: DESS2025-042

X-Ray Computed Tomography for Quality Assurance and Reliability

Fuzail Shad
Wright State University
Arashdeep Singh
Wright State University
Daniel Young
Wright State University
Ahsan Mian
Wright State University

X-ray Computed Tomography (XRCT) is a critical non-destructive method to examine internal structures, which is a necessary step to ensure quality and reliability in advanced manufacturing, such as additive and electronics manufacturing. Traditional 2D cross-sectioning methods are usually destructive that render the sample unusable for further testing or usage, limiting their effectiveness in quality control and failure analysis. This study provides a deeper perspective on the versatility and quantitative power of XRCT across three different applications. First, we used XRCT on a 3D printed aluminum cylinder to image the inside of the structure and find out defects such as voids and inclusions, and quantify them. This can determine the mechanical performance of the structure and assure its quality. Second, XRCT was applied to several IC chips to study chip-level electronic packaging and to ensure reliability in high-density electronics features like solder joint integrity and wire bond placement. Finally, this nondestructive method was used for micro-interconnect characterization, providing high-resolution data on geometric uniformity and layer consistency of ink-jet printed nano-silver traces on substrates that ensures print quality of the material and method. From the above examples it can be concluded that XRCT is an essential tool to ensure quality control and reliability of materials and manufacturing methods. Keywords: X-ray CT; Additive Manufacturing; Electronic Packaging; Quality Assurance; Reliability

Abstract ID: DESS2025-048

Additive Manufacturing of Advanced Ceramic Materials: A review of technologies, Advantages, Challenges and Applications

Jagan Sivamani
Wright State University
Jagan Sivamani
Wright State University
Arashdeep Singh
Wright State University
Ahsan Mian
Wright State University

Additive Manufacturing (AM) refers to as 3D printing, the method of converting a digital 3D model into a tangible three-dimensional item, typically through computer guidance and commands. Essentially, it produces an item from scratch, representing an eco-friendly technology with minimal waste. This review offers a detailed look at the latest additive manufacturing (AM) methods used for advanced ceramics. These methods include material extrusion, binder jetting, powder bed fusion, vat photopolymerization, and direct ink writing. The discussion emphasizes the significant benefits of additive manufacturing for ceramics, including the ability to create complex geometries, enable customization, integrate multiple functions, and reduce costs and production time for small-scale manufacturing. At the same time, it provides a critical evaluation of the ongoing challenges, such as material brittleness, high sintering requirements, shrinkage and warping during densification, limited feedstock diversity, anisotropic behavior, and difficulties in maintaining consistent quality.

Aerospace Engineering

Abstract ID: DESS2025-020

Using Basic Linear Algebra subroutines to calculate force and moment data from wind tunnel balances

Daniel Davidar
Air Force Research Laboratory

Awaiting public release.

Undergraduate Research Projects

Abstract ID: DESS2025-041

Optimizing Machine Learning Models for Real-Time Ultrasonic Quality Monitoring in Pharmaceutical Tablet Manufacturing

Christian Di Spigna
Cedarville University
Tipu Sultan
** Other (please contact webmaster)
Cetin Cetinkaya
** Other (please contact webmaster)

Awaiting public release.