The United States Air Force Academy (USAFA) is a commissioning source for the U.S. Air Force, and as such, it strives to provide each graduate a well-rounded undergraduate education, grounded in a Science, Technology, Engineering, and Math (STEM) curriculum, in addition to military officership training to help each student prepare to become a leader in the Air Force immediately following their graduation.Mechanical Engineering 220 -Fundamentals of Mechanics (ME 220) is one of many STEM courses that all students, both engineering and nonengineering majors, are required to take.The curriculum focuses on statics and mechanics of materials.This course plays two key roles in the overall curriculum at the USAFA.It is a required, or core, course and is most often the first of four engineering courses that every student is required to take, usually during their sophomore year.It is also the foundational course for students pursuing a degree in Mechanical Engineering or in Civil and Environmental Engineering.In its role as a core course, ME 220 is expected to satisfy certain institutional learning outcomes, including teaching students how to think critically, how to communicate clearly in a technical context, and how to apply engineering methods, design methodology in particular.In its current state, the course falls short in meeting several of the institutional outcomes.In a series of conversations and meetings, the department faculty and leadership identified various deficiencies in the course with respect to meeting these outcomes, the most prominent of which was the lack of curriculum dedicated to teaching and practicing engineering design.To better achieve these outcomes, the course was redesigned during the summer of 2021, and three experimental sections of this course were taught to randomly assigned students during the Summer session and during the Fall semester of 2021.Based on what was learned from these sections, the redesigned course will be taught by 7 instructors to approximately 400 students in 17 sections during the 2022 Spring semester.A critical piece of the redesign is a new final project that focuses on a design-build-test experience.In this paper, the authors will discuss the previous course and how it has been adjusted to better address the institutional outcomes.They will explain which topics were removed and what lessons and design experiences were added to adequately fulfill the USAFA's objective of developing future Air Force officers who have a solid educational background in STEM.They will also compare the previous course's final project with the new final project.The methods and tools used to ensure the new course and lesson objectives align with the course assessments, the institutional outcomes, and subsequent core engineering courses will be described.Preliminary findings from the assessment data will be presented, and plans for a more robust assessment of the changes will be discussed.

As time progresses, space becomes more congested with micrometeoroids and orbital debris (MMOD). This increase in debris flux poses a critical threat to satellites already in orbit, manned missions, and future orbiting spacecraft. To reduce the operational impact of MMOD collisions, current protection schemes use Whipple Shields, an aluminum plate with a prescribed standoff distance, as the basis for protection. These aluminum shields are manufactured and installed on the space vehicle while on Earth, which constrains their size and shape, and ultimately, their effectiveness. These fixed shields also cannot be repaired if they are damaged during service. This work describes a prototype shield system that can be additively manufactured and installed while the vehicle is in orbit. This system, designed for manufacture via three-dimensional printing in space, would allow an operator to add shielding to a vehicle once in orbit, protecting it against MMOD traveling at hyper velocities. These on-orbit manufactured shields allow specific tailoring to more-efficiently and effectively meet mission requirements. CTH finite element code was used to simulate hypervelocity impacts (HVI) on computer-aided design (CAD) models of the prototypes. These simulations used structures made of analogous materials such as polycarbonate to make and evaluate new design parameters. The performance of different design parameters in simulations drove a redesign of the original prototype. These new designs were additively manufactured with ULTEM 9085 and underwent testing at a hypervelocity impact laboratory. Six prototypes were tested and successfully survived a hypervelocity projectile impact, indicating their potential effectiveness as spacecraft MMOD shielding.

Demand is increasing for effective online tools to perform collaborative engineering design by geographically separated teams. In particular, tools that facilitate the concept ideation phase of the engineering design process are sought for immediate implementation in product design. In this work, researchers conducted a literature review, interviews with practicing engineers, and a thorough web search to identify available tools and the desired features and requirements. A set of 100 web-based collaborative tools were identified then filtered down to 18 candidates which met the minimum criteria. These 18 were systematically evaluated by the researchers who rated their satisfaction of 11 requirements. The five highest rated finalist platforms were more thoroughly tested by design teams who used the platforms in design sprint activities. Evaluator ratings and feedback were collected at multiple points and several best practices were discovered during testing. Conceptboard(3) received the highest evaluator ratings, with few negative comments, and is expected to be an effective tool for collaborative engineering design.

Falls in the elderly is an ongoing problem and is one of the leading causes for trips to the emergency room, hospitalizations, serious injuries, and expensive health care costs. However, many times the relationship between sleep quality and falls oftentimes is overlooked. Here we present a case of a 75-year-old female admitted for sustaining 4-5 falls per day for many years that was ultimately found to be due to chronic sleep deprivation. She was treated with non-invasive positive pressure ventilation (NIPPV) for her complex sleep apnea and hypercarbia. Subsequent follow-up revealed significant decrease in her number of daily falls down to <1 per day. This case further adds to the data showing a link between treating sleep apnea in the elderly and a reduction in falls. Abbreviations : CT – computed tomography ; CPAP – continuous positive airway pressure ; EPAP – expiratory positive airway pressure ; Lpm – liters per minute ; MSLT – multi-sleep latency test ; NIPPV – non-invasive positive pressure ventilation ; OSA – obstructive sleep apnea ; PFTs – pulmonary function tests ; Pmax – pressure max ; REI – respiratory event index ; REM – rapid eye movement ; SpO2 – oxygen saturation

Abstract Introduction Each year, 3 million older people are treated in emergency departments for fall-related injuries. These falls can lead to serious injuries and expensive health care costs. Some have looked into the relationship between chronic sleep disturbances and falls linking chronic sleep deprivation or excessive sleep to falling. Here, we present a unique case of chronic sleep deprivation causing sleep attacks or micro-sleeps with atonia causing falls. Report of case(s) We present a 75-year-old F with a history of increased daily falls up to 4x per day that began 3 years ago. She denies any triggering events, auras, frequent tripping, loss of balance or weakness. Reportedly, she will be walking along then suddenly falls. She is aware that she is falling yet feels as though she cannot prevent/stop the fall or break her fall. No one has witnessed her fall, but is frequently found lying on the floor. She has never sustained a serious injury as a result of her falls. She has an 8 year history of restless legs syndrome treated with ropinirole and a 10 year history of obstructive sleep apnea (OSA) treated with CPAP. Her general bedtime is 2200 and wake-time is 0400 with an average 3–4 hrs of quality sleep per night for many years. She endorses severe daytime hypersomnolence and chronic hypoxemia on 3L home oxygen. We hypothesized her falls were secondary to sleep attacks or micro-sleeps where she enters REM sleep and develops atonia. Nocturnal sleep study followed by MSLT showed severe OSA with severe, persistent daytime sleeping with REM sleep and atonia. She had a mean sleep latency of 2 minutes with 1 sleep-onset REM period. We started NIPPV with supplemental oxygen treatment, and within 4 months her daytime hypersomnolence resolved, exercise intolerance improved, saturations improved to 89–90% on room air, and has <1 fall per day. Conclusion Here, we presented a unique case of a 75 yo F with recurrent falls secondary to chronic sleep deprivation causing micro-sleeps involving REM sleep and atonia. She was treated with NIPPV which improved her oxygenation and reduced her number of falls to <1 per day. Support (if any):

Frequent and effective design evaluation is foundational to the success of any product development effort. Products that will be used, installed, or otherwise handled by humans would benefit from both an evaluation of the product itself (the physical embodiment of the technology, termed technology), and the steps a user should take to use that technology (termed tactics). Current methods for the evaluation of tactics are scattered across multiple research areas, and are often inaccessible to engineers who have no prior experience with them. Furthermore, the existing tactics evaluation methods often focus mostly on the use of a product and do not simultaneously consider technological performance. In this paper we present a method for the simultaneous evaluation of tactics and technology during the conceptual design stage. To achieve this, we propose three contributions; an approach for representing tactics concepts, a set of criteria for tactics evaluations, and a means for presenting the results of the technology/tactics evaluation to facilitate team ideation.

The initial phases of the design process including interactions with stakeholders, ideation of concept candidates, and the selection of the best candidates have a large impact on the success of a project as a whole. They also tend to be the most unstructured portion of the project, and are often marginalized by teams who assume they already understand stakeholder needs and the best solution paths to pursue. Design researchers have developed methods shown to increase the creativity and divergent thinking of the design team during these initial phases of design. Nevertheless, these methods often rely on only a vague or amorphous representation of the design space (the set of all possible concepts the design team could feasibly select to meet the objective of the project). In this paper, we introduce a particular design-space structure that can help teams ideate and evaluate their ideation, thus improving the early phases of the design process. The design space presented here is a vector space with a basis of technology (the physical product people will use) and tactics (the procedure for using the product). Also presented are definitions, principles, and sub-theories that facilitate the creation and use of technology-tactics plots to represent the design space. Considering the design space in this structured way, the design team can gain valuable insights that improve the effectiveness of the initial stages of design, and may yield additional benefits to the design process as a whole, if further developed.

This paper provides a brief overview of the activities undertaken by the Missile Facet of NATO STO AVT 316 (Vortex Interaction Effects Relevant to Military Air Vehicle Performance) since its first meeting in April 2018. Rather than setting out to provide definitive technical statements, a broader, more narrative approach is taken towards summarising some of the key developments that have occurred during the early stages of the facet’s existence. To date, work has focussed on investigating a blind test case (CFD_OTC1) based on a generic missile airframe at a supersonic flight condition. Attention is focussed on the predicted total rolling moment coefficient, the polarity of which determines the airframe’s local static roll stability. While the facet is still some way from demonstrably achieving verified CFD solutions at the flight condition of primary interest, there is now little doubt that the airframe will be predicted to be locally unstable in roll.

Modern computational fluid dynamic simulations of flows about naval vessels produce an enormous amount of flow-field data. The computations are performed in order to model details of the erratic unsteady flows that can occur about naval superstructures. The flow-field data can then be used in flight simulators for naval pilot training purposes. Often, however, far too much data are generated for the flight simulators to process in real-time. This paper demonstrates the use of both proper orthogonal decomposition and Fourier series decomposition approaches for airwake dataset compression. The proper orthogonal decomposition method is used for compressing airwake data in the time domain, and Fourier series decomposition is used for compressing airwake data in the spatial coordinates. The approaches are applied to airwake data for a simplified frigate vessel model. A separate aircraft tanker configuration is also examined in order to demonstrate that the level of numerical precision can have an effect on the dataset compression results. Both approaches are effective at reducing airwake dataset size while preserving the dominant flow-field features, and both approaches are inexpensive and straightforward to implement. The level of dataset compression ultimately depends on the level of accuracy required by the user.

Abstract Student capstone teams have varying degrees of success in meeting the expectations of their project sponsors. Keeping sponsors happy is important to these programs in order to ensure continued support from these industry representatives, so finding ways to improve project outcomes is critical. In order to find blind spots that students may have been left with after their first 6–7 weeks of instruction, we conducted structured interviews with students in capstone programs at Brigham Young University and the US Air Force Academy. These interviews were then transcribed, coded, and analyzed for themes that may have been well understood or misunderstood by students. We found that a significant number of students had not understood concepts such as a design being more than a prototype, that sponsors have expectations for the tradeoffs between product cost and performance, or that they need to be thinking about how their designs might be deployed. It was also interesting to note that most students also reported feeling confident in their understanding despite their apparent lack thereof, indicating that these could represent major blind spots for students. We propose that developing methods for teaching these principles early on will help students see more clearly what their end goals need to be, and thus help them be more successful in delivering desirable designs.

In rock climbing, finger strength is directly related to performance. Here, a novel device is described to enhance finger strength training or aid in rehabilitation of finger injuries. The device incorporates load cells into an existing hangboard to measure finger force, record it and display it to the athlete in real time. The device was characterized for accuracy, linearity, hysteresis and repeatability, and found to have a resolution of ±01.5 N, sample rate of 10 Hz, and linearity of 0.9998. Preliminary athlete trials of the device verified its ability to more accurately record training exertion, that biases exist between the right and left hands of climbers and that this real-time performance feedback can improve training quality.

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In elite rock climbing, finger strength is critical, and is directly related to performance. A hangboard, composed of sets of artificial climbing grips to hang from, is often used by climbers to improve their finger strength. While some research has studied training protocols for climbing, virtually no published research exists addressing the specific enhancement of training equipment to improve training effectiveness. Here we seek to show that hangboard design, especially novel features included in the Rock Prodigy Forge hangboard increases the effectiveness of hangboard training. Recently, this hangboard was developed through an iterative process leveraging modern CAD/CAM techniques. This enabled design engineers to optimize the hangboard for improved training benefit and reduced injuries. As a result, several innovative features were added to the design including: (a) equation-driven grip edge profiles, (b) drafted pockets, (c) novel grip designs, (d) improved grip geometry, and (e) improved texture, among other features. The Forge was tested by experienced climbers, and 92% assessed it as more effective than other training tools, with 91% of users able to train harder without fear of injury relative to other training methods, and 86% reporting improved climbing performance. This is a significant and unique result for the sport of climbing.

This paper presents a multidisciplinary framework for the design and analysis of gyrocopter-type airborne wind turbines. In this concept, four rotary wings provide lift to a flying vehicle, and excess power is extracted using gearboxes and generators before being transferred to the ground through electrical conductors embedded in a structural tether. A physical breakdown of the system was performed, and five models were constructed: wind model, rotor aerodynamics, structural mass, electrical system, and tether (structures and aerodynamics). A stochastic optimizer in the framework enforces interdisciplinary compatibility and maximizes electrical power transmitted to the ground under various operating conditions. The framework is then used to explore the design space of this advanced concept in numerous flight conditions. The effect of implementing new technologies was also studied in order to evaluate their effect on the overall performance of the system. It is shown through a 1.3MW design that a gyrocopter-type airborne generator could provide more power than a ground-based wind turbine for a given blade radius, although only a fraction of the available wind power can be harvested using off-the-shelf technologies and components. The work presented in this study demonstrates the challenges of designing a high altitude wind generator and shows that performance is affected by complex interactions between each subsystem. Copyright (c) 2015 John Wiley & Sons, Ltd.

Mini-Design Projects in Capstone: Initial Design Experiences to Enhance Students’ Implementation of Design MethodologyCapstone design courses are intended to provide a culminating experience for seniorundergraduate engineering majors. Universities vary in how they implement the instructionand implementation of the design process in their capstone courses. For example, many have aseparate class in design methods, followed by a one-semester capstone course where teamswork on a “design, build, test” project. Other institutions teach design methodologyincorporated into the capstone design project in what is often a two-semester capstonesequence. In the cases where design methodology is incorporated into a two-semestercapstone course, it is possible that this is the students’ first extensive exposure to designmethods and process. In that case, students may be experiencing methods such as “CustomerNeeds Analysis”, “Functional Decomposition”, “Concept Generation”, “Concept Selection” and“Prototype Planning” for the first time. From a constructivist educational standpoint, it can beproblematic for students to apply these design techniques for the first time on what is often acomplex, real world capstone design problem. One solution to this problem is to incorporate ashort “mini-design” experience at the beginning of the two-semester capstone course. This canallow the students an initial experience with the design methods that can provide a “learningscaffold” for their implementation of the full suite of design methods over the course of a two-semester project. For the last two years, we have implemented two versions of a mini-designproject in our two-semester capstone design sequence. In both cases of our use of the mini-design project, the suite of five core design methods mentioned above were taught in anabbreviated form. However, one year’s mini-design project lasted seven lessons while theother lasted only three lessons. The longer mini-design allowed for greater depth in the initialcoverage of the methods and also provided greater time for prototyping and testing. Of coursethis was at the cost of consuming a greater percentage of the overall time allocated for theactual capstone design project. This paper reports on the implementation details of the mini-design projects, focusing in particular on advantages and disadvantages of the two differentimplementations. Faculty and student feedback indicated that the use of the mini-design doesincrease student familiarity with the design methods. However, more subtle questions such asthe number of lessons allocated for the mini-design and the depth of coverage of the designmethods have much more complicated assessment results.

Recently a novel finger strength training tool for rock climbers, the Rock Prodigy Training Center (RPTC) and its associated training protocol, the Rock Prodigy Method (RPM) were developed. The RPTC incorporates several innovations that improve upon similar, traditional devices to provide a sport-specific, repeatable method for improving finger strength in climbers, and to improve overall climbing performance. After several months of use by climbers around the world, the efficacies of these tools were evaluated by comparing pre- and post-training climbing performance. Training and performance data are presented from 118 athletes which clearly demonstrate that the RPTC and RPM are highly effective at increasing sport-specific finger strength. Finger strength improved an average of 21.5% after only 4 weeks of training, and overall climbing ability improved an average of 2.5 Yosemite Decimal System letter grades after using these training tools.