Search

The technology that we focused on was the biomimetic actuation of microfluidic microcapacitors, which are electrostatically actuated structures that contract and function like biological muscles. Our thesis aims to find the optimal muscle-to-tendon ratio while expanding both the standard and gap design arrays and to find the respective force-density saturation values so predicted force output can be calculated for muscle fibers of a practical size. We also studied if a 3D virtual object can be a suitable model for the human operators’ examination of the artificial muscle and the optimization of its structure. Our results showed a maximum force density saturation of 8800 Pa and 6700 Pa when simulating the standard and gap array respectively with planar polarity wired artificial muscles. The optimal muscle-to-tendon ratio from the data gathered on the standard array simulations is approximately 9 to 1, meaning 90 percent of the surface area of the XY plane represents microfluidic capacitors and 10 percent is dielectric tendon material. The optimal muscle to tendon ratio from the data gathered on the gap array simulations is approximately 75 to 25, meaning 75 percent of the surface area of the XY plane are microfluidic capacitors, and 25 percent is both the dielectric material and gaps.

The Army is procuring the Integrated Visual Augmentation System (IVAS) system to enable enhanced night vision, planning, and training capability. One known limitation of the IVAS system is the limited ability to portray virtual entities at far ranges in the outdoors due to light wash out, accurate positioning, and dynamic occlusion. The primary goal of this research was to evaluate fixed three-dimensional (3D) visualizations to support outdoor training for fire teams through squads, requiring target visualizations for 3D non-player characters or vehicles at ranges up to 300 m. Tools employed to achieve outdoor visualizations included GPS locational data with virtual entity placement, and sensors to adjust device light levels. This study was conducted with 20 military test subjects in three scenarios at the Naval Postgraduate School using a HoloLens II. Outdoor location considerations included shadows, background clutter, cars blocking the field of view, and the sun’s positioning. Users provided feedback on identifying the type of object, and the difficulty in finding the object. The results indicate GPS only aided in identification for objects up to 100 m. Animation had a statistically insignificant effect on identification of objects. Employment of software to adjust the light levels of the virtual objects aided in identification of objects at 200 m. This research develops a clearer understanding of requirements to enable the employment of mixed reality in outdoor training.

This work investigates whether a tachistoscope on a virtual reality (VR) platform can increase one’s ability to memorize and rapidly recognize objects. Theses abilities are relevant to an array of military requirements. Current procedures mostly utilize flash cards and PowerPoint slides. A tachistoscope (ta-kiss-stow-scope) is an image-flashing device with precise control of the image presentation time. Since the early 1900s they were used to assist with memorization and recognition. One famous example is work done by Renshaw in the 1940s to improve pilots’ ability to recognize tanks, aircraft, and ships (Renshaw, 1945). Our study utilized this technique on modern-day VR and computer platforms. It simplified the use of a tachistoscope and will enable units to customize training packages. This study trained individuals to recognize 40 aircraft over eight training sessions. Training session one began with ten aircraft, and five aircraft were added in each subsequent session. Questions captured three variables: correct/incorrect answer, reaction time, and confidence. Participants were in one of three groups: tachistoscope on a VR platform, tachistoscope on laptop, or computer-based flashcard (control). Results indicate a significant increase in memorization from pretest to posttest for all groups. Furthermore, there was a nonsignificant improvement in reaction time from pretest to posttest across all groups.

Efficient maintenance is critical for the U.S. Navy to sustain surface fleet operational readiness, capability, and capacity. Efficient maintenance relies on the ability to quickly locate needed maintenance items. The current process to locate critical maintenance items relies on the written description of a work order, which offers little description and ambiguity of the exact physical location of the maintenance item, creating inefficiencies in repairs, and cost and schedule delays. Augmented Reality (AR) has been shown to improve maintenance efficiency in the private sector; we provide empirical evidence to suggest the U.S. Navy should consider AR adoption for maintenance for certain use cases. We conducted an experiment in which 20 subjects were randomly assigned to locate visible unobstructed objects in two rooms that represented shipboard compartments using either the current maintenance process or with AR guided assistance. Performance was measured by time to locate items, accuracy, and the confidence in having identified the proper item. Results indicated that use of AR guidance led to considerably better performance on all measures, in terms of both statistical significance and practical importance. This research shows evidence that AR can potentially close the capability gap existing within the current process.

The risk of traumatic brain injury (TBI) is significantly higher among Veterans compared to non- Veterans. Access to treatment for TBI and post concussive symptoms is sometimes difficult, because of barriers related to distance, finances, and public safety (i.e., COVID-19 infection). Virtual reality rehabilitation (VRR) offers an opportunity to incorporate a virtual space into a rehabilitation environment. To our knowledge, VRR has not been used to assist Veterans with TBI and related health problems with Instrumental Activities of Daily Living (iADLs). The purpose of this study is to investigate the usability of a novel VRR ADL and iADL training protocols, developed by the Gaming Research Integration for Learning Laboratory (GRILL® ) at the Air Force Research Laboratory, for cognitive rehabilitation for Veterans with a TBI. We deployed a prototype protocol among healthcare providers (n 20) to obtain feedback on usability, task demand, and recommended adjustments. Our preliminary analysis shows that providers found the VRR protocol involved low physical demand and would likely recommend it to their patients. Although they had some concerns with vertigo-like symptoms from using a digital technology, they believed the protocol would improve iADL functioning and was a good addition to pre-existing rehabilitation protocols. These outcomes provide justification for more impactful studies investigating the effectiveness of this protocol among Veterans with TBI.

Intuitive System Training

Project Summary: The Department of Defense (DoD) is relying more heavily on virtual environment and augmented reality for training purposes. However, little is known as to whether the use of a virtual environment (VE) and augmented reality (AR) are as effective in training tasks that require fine motor skills. This research measured human precision and efficiency by comparing augmented reality cued (ARC) and traditionally cued (TC) maintenance procedures in five tasks designed to elicit absolute, cumulative, absolute referential, and complexity errors across both ARC and TC conditions. Results indicate ARC procedures are statistically more efficient for human precise placement tasks of small parts, while precision is roughly equal. The assembly task, analogous to an assembly procedure, is statistically both more efficient and more precise using ARC vice TC procedures. Results indicate that ARC procedures for small part placement and assembly tasks are more efficient, faster, and in most cases at least as precise as TC procedures.

An intelligent tutoring system (ITS) is paired with U.S. Navy immersive virtual trainer for shiphandling called Conning Officer Virtual Environment (COVE) to monitor students' performance and provide spoken feedback. The feedback can be improved by incorporating the cognitive state of shiphandlers through analysis of their attention-allocation patterns from eye-tracking data. This thesis research contains a pilot study directed toward analyzing the eye-tracking data of expert and novice shiphandlers. We examined the relationship between a shiphandler's experience level, attention-allocation patterns, and performance during a simulated shiphandling exercise. Five novice and four expert shiphandlers from the U.S. Navy Surface Warfare Officers School participated in the study. Our analyses indicates expertise differences in shiphandling performance, general eye-tracking measures, scan transitions, as well as time distribution between different areas of interest. The experts' superior shiphandling performance was linked with having targeted and tight attention-allocation patterns that focused only on the relevant areas of interest. Novices' attention-allocation patterns were highly scattered and irregular. Results suggest that incorporating the ideal attention-allocation patterns of the experts into the ITS could improve its feedback to novice shiphandlers by telling novices where they should look and when. The study is based on a small sample size; therefore, further data collection should be performed to confirm the results.

A collaborative project between Naval Postgraduate School (NPS), Veterans Affairs Palo Alto Health Care System (VAPAHCS), Defense and Veterans Brain Injury Center (DVBIC), and neuroFit Inc., was developed to: 1) assess the efficacy of the Comprehensive Oculometric Behavioral Response Assessment (COBRA) as a screening method for mild-to-moderate Traumatic Brain Injury (TBI) in veterans, and 2) evaluate the usability of the neuroFit Oculometric Neurological Examination (ONE) device in military medical facilities. COBRA metrics used to characterize oculometric signs associated with TBI came from two published samples: a 41-subject control sample and a 34-subject civilian TBI sample comprised of mild (loss of consciousness (LOC)<30 min), moderate (30 min24 h) TBIs. The control sample was compared to the eight-subject veteran TBI sample (age range: 27–55 years; 8 males) from the VAPAHCS, comprised of mild (n=7) and moderate (n=1) TBI diagnoses and posttraumatic amnesia (PTA) (n=4). Results demonstrated a significant (p = .02) difference between the control and veteran TBI samples. COBRA metrics accurately detected TBIs at a rate of 77%. Results indicate the COBRA method is viable for TBI screening in military medical facilities and may be suitable for diagnosing chronic visual problems related to mild and moderate TBI.

This thesis supports the Army's mission to establish a measure for cognitive agility in soldiers. It examines attention-allocation patterns as quantified by eye-tracking data collected while subjects played a military-relevant cognitive agility computer game (Make Goal), to determine whether certain patterns are associated with effective performance. It also investigates the effects of stress on cognitive agility as measured by attention allocation. Methods: Forty military officers were randomly assigned to a stress or control group. Stress level was manipulated by timed turns and experimenter behavior. Results: Eye-tracking data was analyzed in terms of regions of interest on which subjects focused their cognitive workload. Results were analyzed by stress and control group and top and bottom ten performers. The stress and control groups showed similar attention-allocation patterns. The high performers attended more to the important information and made more optimal selections than poor performers. Discussion: Results are discussed in the context of the Yerkes-Dodson stress model. Eye-tracking data revealed attention-allocation patterns associated with higher performance. In order to better detect the impact of stress on Cognitive Agility, an experiment that includes a wider range of stress levels is needed.

Purpose Current Army doctrine stresses a need for military leaders to have the capability to make flexible and adaptive decisions based on a future unknown environment, location and enemy. To assess a military decision maker’s ability in this context, this paper aims to modify the Wisconsin Card Sorting Test which assesses cognitive flexibility, into a military relevant map task. Thirty-four military officers from all service branches completed the map task. Design/methodology/approach The purpose of this study was to modify a current psychological task that measures cognitive flexibility into a military relevant task that includes the challenge of overcoming experiential bias, and understand underlying causes of individual variability in the decision-making and cognitive flexibility behavior of active duty military officers on this task. Findings Results indicated that non-perseverative errors were a strong predictor of cognitive flexibility performance on the map task. Decomposition of non-perseverative error into efficient errors and random errors revealed that participants who did not complete the map task changed their sorting strategy too soon within a series, resulting in a high quantity of random errors. Originality/value This study serves as the first step in customizing cognitive psychological tests for a military purpose and understanding why some military participants show poor cognitive flexibility.

Effective decision-making is a hallmark of military leadership, and development of decision makers is critical to military strategy. The Cognitive Alignment with Performance-Targeted Training Intervention Model (CAPTTIM) was developed to aid training of optimal decision-making. Cognitive state suggests a subject is exploring the decision environment as opposed to exploiting it, and decision performance classifies whether a subject is making optimal decisions. Using a color-coded structure combining cognitive state and decision performance, CAPTTIM indicates whether those factors are aligned for optimal decision-making--exploiting the environment and making optimal decisions--or not. The focus of this thesis was to identify each subject's CAPTTIM status in real time and, when decision performance was misaligned, provide feedback to influence the subject's future decisions. Through a human-subject experiment (n = 34), we classified decision-makers' CAPTTIM status in real time. We randomly assigned 17 subjects to receive tailored feedback during execution of a decision task (feedback group), and trend analysis reveals the feedback group to be more likely to reach optimal decisions than a control group. These results imply that training systems could be tailored to the individual and that methods used to instruct effective decision-making may expand to include real-time understanding and intervention.

Current Army doctrine stresses a need for military leaders to have the capability to make flexible and adaptive decisions, based on a future unknown environment, location, and enemy. To assess a military decision-maker’s ability in this context, we modified the Wisconsin Card Sorting Test (WCST), which assesses cognitive flexibility, into a military-relevant map task. Thirty-four military officers, from all service branches, completed the map task. The purpose of this study was to (1) modify a current psychological task that measures cognitive flexibility into a military-relevant task, and (2) understand the underlying causes of individual variability in the decision making and cognitive flexibility behavior of active duty military officers on this task. Results indicated that nonperseverative errors were a strong predictor of cognitive flexibility performance on the map task. Decomposition of nonperseverative error into efficient errors and random errors revealed that participants who did not complete the map task changed their sorting strategy too soon within a series, resulting in a high quantity of random errors. This study serves as the first step in customizing cognitive psychological tests for a military purpose and understanding why some military participants show poor cognitive flexibility.