Digital Human Modeling for Universal Design

Contributors

<div class="section abstract"><div class="htmlview paragraph">The objective of this effort is to create a methodology to posture and position equipped manikins in Computer-Aided Design (CAD) software for ground vehicle workstation design. A collaborative effort is taking place to evaluate the current practices used to posture and position both physical and digital human representations. The goal of the group is to determine how best to utilize posture and position data to update positioning procedures. Data from the Seated Soldier Study and follow-on studies is being utilized to develop statistical models using multivariate analysis methods. Design is the first area of focus across the broader design-develop-evaluate process. The products to address this need are parametric CAD accommodation models with imbedded Digital Human Models (DHMs). Developing updated positioning procedures for each of the manikins will provide a traceable justification for positioning manikins based on Soldier data.</div></div>

<div class="htmlview paragraph">McDonnell Douglas recognizes that advancing technology is moving industry toward a totally electronic data transfer environment. The question was raised as to how did this relate to MDC's contractual obligations.</div> <div class="htmlview paragraph">A study of the data requirements, established by Contract, for several MDC component companies was conducted. This study identified approximately 2000 data requirements drivers (contractual specifications/standards) imposed on the various MDC components.</div> <div class="htmlview paragraph">Four areas of focus for these requirements documents were identified: product definition/reprocurement data, configuration management, technical publications (ILS) and cost/management data. The relationship of these requirements to the business environment was identified and the significance they hold toward effectively implementing a “paperless” business environment analyzed.</div>

The acoustics education program at the Georgia Institute of Technology (Georgia Tech) is run by members of the Acoustics and Dynamics research area group from the School of Mechanical Engineering. We will briefly review the scope of this program in terms of education and research activities

<div class="htmlview paragraph">Multidisciplinary design and analysis has become the normal mode of operation within most aerospace companies, but the impact of these changes have largely not been reflected at many universities. In an effort to determine if the emergence of multidisciplinary design concepts should influence engineering curricula, NASA has asked several universities (Virginia Tech, Georgia Tech, Clemson, BYU, and CaI Poly) to investigate the practicality of introducing the concepts within their undergraduate curricula. A multidisciplinary team of faculty, students, and industry partners evaluated the aeronautical engineering curriculum at Cal Poly. A variety of ways were found to introduce multidisciplinary themes into the curriculum without adding courses or units to the existing program. Both analytic and educational tools for multidisciplinary design of aircraft have been developed and are in the process of being implemented.</div>

<div class="htmlview paragraph">The Georgia Tech FutureTruck Team has designed a strong parallel split-hybrid powertrain for the model year 2002 Ford Explorer SUV. The modified powertrain uses a Lincoln LS 3.0L, V-6, DOHC, aluminum engine driving the rear axle. An AC-150 from AC Propulsion is coupled to the front wheels through a 3.75:1 Auburn Gear speed reducer. This split-hybrid structure fits well into the Explorer and is to manufacture. The interior cabin has been maintained in a stock configuration by carefully integrating the added instrumentation and electric drive controls into the dash and console. The toque-blending hybrid electric control is designed to be charge sustaining such that the refueling procedures match those of the stock vehicle. When fully operational, this powertrain is expected to yield a net 25% increase in fuel efficiency while lowering emissions without any sacrifice in customer acceptability.</div>

Supporting Pacific Indigenous Computing Excellence (SPICE) is based on unique expertise and proven models established through a partnership between the Texas Advanced Computing Center at the University of Texas at Austin, Chaminade University of Honolulu and Georgia Institute of Technology (Georgia Tech). The SPICE program leverages shared partnership experiences to address two goals: 1) Perform original research and program development to bridge computation and culture --- developing culturally-consistent conceptual and practical frameworks for thinking about big data problems and communicating student outcomes and attainment to family, community and kupuna (Hawaiian wisdom figures); and 2) Implement an in situ Data Science, Analytics and Visualization (DSAV) Summer Immersion Experience (SIE) as a summer program in Hawai'i to provide a month-long summer immersion program in data science, visualization, and virtual reality to Native Hawaiian and Pacific Islander (NHPI) and disadvantaged students. In this paper, we present the framework for this effort, with relevant educational, and cultural research to justify decisions made to date.

Optics is a field that deals with sources, components, and detectors. Its practice requires that students be familiar with many techniques from the simple measurement of the radius of curvature of a lens surface with a dial gauge spherometer to the analysis of figure errors of the same surface using a phase-shifting interferometer. In this article we describe the laboratory courses available to students in the Applied Optics program in the School of Physics, which is part of the Center of Optical Science and Engineering at the Georgia Institute of Technology. The experiments and projects are intended to provide the student with experiences that will prepare them for work in optics after they graduate.

Acoustics at Georgia Tech spans multiple schools, including Mechanical Engineering, Electrical Engineering, Aerospace Engineering, Biomedical Engineering, Psychology, Music, Physics, Mathematics, and Architecture. The program began over 50 years ago and strengthened considerably in the 1960s and 1970s after Eugene Patronis, Ben Zinn, and Allan Pierce joined the faculty in the Schools of Physics, Aerospace Engineering, and Mechanical Engineering, respectively. Since then hundreds of students in acoustics have graduated and hold positions in academia and industry around the world. Currently the School of Mechanical Engineering has 11 academic faculty members with primary interest in acoustics and dynamics. Areas of research include architectural acoustics, psychoacoustics, noise control, environmental acoustics, sustainable systems design, underwater acoustics, bioacoustics, ultrasonics, active/passive control, fluid-structure interaction, nonlinear acoustics, acousto-optics, micromachined sensors and actuators, vibration of nonlinear and frictional systems, shock and vibration isolation, structural acoustics, wave propagation, and structural health monitoring. Masters and Ph.D. level programs are offered in addition to various undergraduate courses. The depth of knowledge at Georgia Tech facilitates a variety of collaborations, allowing students a multi-disciplinary education in the science and application of acoustics. Student interactions are further facilitated by a number of organizations on campus, including a recently established student chapter of the ASA.

Quality of service is important feature for a High Performance Computing Center (HPC) center like Partnership for an Advanced Computing Environment (PACE) center in Georgia Institute of Technology (Georgia Tech). The user’s job fails running on a HPC center may due to a spectral of reasons, one of major contributor is the hardware and network failure. Reducing the hardware failure rate can significantly increase a data center’s quality of service as well as reducing the cost of human intervention. This is critical during PACE’s transition to a fee-based service model in which uptime correlates directly with revenue. PACE has around 9 millions jobs each year with 12% of job failure rate. In order to extend service life of hardware and reduce the potential failure and data center’s cost, we present a machine learning method to understand the center’s host usage pattern. By clustering the hosts based on multiple features, we reshuffle the host list to avoid the hosts being overused over time. We build a test framework which runs the complex combination of experiments, and presents the ad hoc comparisons. We intend to make the machine learning method in a rack aware fashion, and show the meaningful result with rack information included.

The IEEE Power Electronics Society (PELS) Atlanta Chapter recently partnered with the NCAB Group to deliver a workshop on printed circuit board (PCB) design and manufacturing on 4 October 2022. The event was held at Georgia Institute of Technology (Georgia Tech) and was significant for the PELS Atlanta Chapter because it was its first in-person event since the Covid-19 pandemic and one of the IEEE Day events.

A new diagnostic for the quantification of Sauter mean diameter in high-pressure fuel sprays has been recently developed using combined optical and X-ray measurements at the Georgia Institute of Technology and Argonne National Laboratory, respectively. This diagnostic utilizes liquid scattering extinction measurements from diffuse back-illumination imaging, conducted at Georgia Tech, and liquid absorption measurements from X-ray radiography, conducted at Argonne’s Advanced Photon Source. The new diagnostic, entitled the scattering–absorption measurement ratio, quantifies two-dimensional distributions of path-integrated Sauter mean diameter, enabling the construction of the spatial history of drop size development within practical fuel sprays. This technique offers unique benefits over conventional drop-sizing methods in that it can be more robust in optically dense regions of the spray, while also providing high spatial resolution of the corresponding droplet field. The methodology for quantification of Sauter mean diameter distributions using the scattering–absorption measurement ratio technique has been previously introduced and demonstrated in diesel sprays using the Engine Combustion Network Spray D injector; however, a more detailed treatment of measurement uncertainties has been needed. In this work, we present a summary of the various sources of measurement uncertainty in the scattering–absorption measurement ratio diagnostic, like those due to the experimental setup, data processing methods, and theoretical assumptions, and assess how these sources of uncertainty affect the quantified Sauter mean diameter. The spatially resolved Sauter mean diameter measurements that result from the scattering–absorption measurement ratio diagnostic will be especially valuable to the engine modeling community for the quantitative validation of spray submodels in engine computational fluid dynamics codes. Careful evaluation and quantification of measurement uncertainties are important to support accurate model validation and to ensure the development of more predictive spray models.

<div class="htmlview paragraph">The majority of aerospace products currently being produced were created using computer-aided design systems. In conjunction with these design tools, some manufacturers are also using computer-driven human models to determine the ergonomic characteristics of their designs. While these human modeling systems are effective at determining a variety of ergonomic parameters they are somewhat costly to purchase and use and are limited by their modeling assumptions. This paper will present a low cost alternative to computer-driven human modeling which may provide utility to manufacturers in determining their products' ergonomic characteristics. This alternative is the establishment and use of a pool of knowledgeable anthropometric test subjects for the evaluation of products.</div>

<div class="section abstract"><div class="htmlview paragraph">As light electric vehicles (LEVs) gain popularity, the development of efficient and compact on-board chargers (OBCs) has become a critical area of focus in power electronics. Conventional AC-DC topologies often face challenges, including high inrush currents during startup, which can stress components and affect system reliability. Furthermore, DC-DC converters often have a limited soft-switching range under light load conditions, leading to increased switching losses and reduced efficiency. This paper proposes a novel 6.6 kW on-board charger architecture comprising a bridgeless totem-pole power factor correction (PFC) stage and an isolated LLC resonant DC-DC converter. The main contribution lies in the specific focus on enhancing startup behavior and switching performance. In PFC converters, limiting inrush current during startup is crucial, especially with fast-switching wide-bandgap devices like SiC or GaN. Conventional soft-start techniques fall short in of ensuring smooth voltage transitions. Moreover, maintaining stable operation across a universal input voltage range and achieving a high-power factor under light load conditions remain persistent challenges. Although resonant converters are widely used for their natural soft-switching ability, achieving zero voltage switching (ZVS) over a wide range of loads, especially at light load conditions, is still a technical challenge. Existing solutions rely on complex control strategies or hardware modifications, which increase cost and design complexity. The proposed architecture was modeled and simulated using MATLAB/Simscape to assess dynamic and steady-state behavior under a range of operating conditions. Results demonstrated high input power factor, line/load regulation, and switch-node waveforms to confirm ZVS operation. Additionally, the proposed charger exhibits low harmonic distortion, ensuring compliance with IEC 61000-3-2 power quality standards. These findings confirm the topology’s effectiveness for high-performance LEV charging and set a strong foundation for future experimental validation and hardware development.</div></div>

This article defines universal design for learning (UDL) and presents examples of how universally designed technology hardware and software applications benefit students with disabilities who are majoring in science, technology, engineering, or mathematics (STEM) majors. When digital technologies are developed without incorporating accessible design features, persons with disabilities cannot access required information to interact with the information society. However, when accessible technology and instruction are provided using UDL principles, research indicates that many students benefit with increased achievement. Learning through universally designed and accessible technology is essential for students with disabilities who, without access, would not gain the skills needed to complete their degrees and access employment and a life of self-sufficiency. UDL strategies enhance learning for all students, including students with disabilities who are majoring in STEM, which are among the most rigorous academic disciplines, but also among the most financially rewarding careers.