• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 58
  • 6
  • 6
  • 5
  • 4
  • 3
  • 2
  • 1
  • 1
  • 1
  • 1
  • Tagged with
  • 115
  • 115
  • 28
  • 23
  • 21
  • 17
  • 17
  • 17
  • 16
  • 16
  • 15
  • 15
  • 14
  • 13
  • 12
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

A Multi-Robot Coordination Methodology for Wilderness Search and Rescue

Macwan, Ashish 13 January 2014 (has links)
One of the applications where the use of robots can be beneficial is Wilderness Search and Rescue (WiSAR), which involves the search for a possibly mobile but non-trackable lost person (i.e., the target) in wilderness environments. A mobile target implies that the search area grows continuously and potentially without bound. This fact, combined with the presence of typically rugged, varying terrain and the possibility of inclement weather, poses a considerable challenge to human Search and Rescue (SAR) personnel with respect to the time and effort required to perform the search and the danger entailed to the searchers. Mobile robots can be advantageous in WiSAR due to their ability to provide consistent performance without getting tired and their lower susceptibility to harsh weather conditions compared to humans. Thus, a coordinated team of robots that can assist human SAR personnel by autonomously performing searches in WiSAR scenarios would be of great value. However, to date, a suitable multi-robot coordination methodology for autonomous search that can satisfactorily address the issues relevant to WiSAR is lacking. The objective of this Dissertation is, thus, to develop a methodology that can autonomously coordinate the search strategy of a multi-robot team in wilderness environments to locate a moving target that is neither continuously nor intermittently observed during the search process. Three issues in particular are addressed: (i) target-location prediction, (ii) robot deployment, and (iii) robot-path planning. The corresponding solution approaches devised to address these issues incorporate the influence of varying terrain that may contain a priori known and unknown obstacles, and deal with unique target physiology and psychology as well as found clues left behind by the target. The solution methods for these three tasks work seamlessly together resulting in a tractable MRC methodology for autonomous robotic WiSAR. Comprehensive simulations have been performed that validate the overall proposed methodology. Moreover, the tangible benefits provided by this methodology were further revealed through its comparison with an alternative search method.
12

A Multi-Robot Coordination Methodology for Wilderness Search and Rescue

Macwan, Ashish 13 January 2014 (has links)
One of the applications where the use of robots can be beneficial is Wilderness Search and Rescue (WiSAR), which involves the search for a possibly mobile but non-trackable lost person (i.e., the target) in wilderness environments. A mobile target implies that the search area grows continuously and potentially without bound. This fact, combined with the presence of typically rugged, varying terrain and the possibility of inclement weather, poses a considerable challenge to human Search and Rescue (SAR) personnel with respect to the time and effort required to perform the search and the danger entailed to the searchers. Mobile robots can be advantageous in WiSAR due to their ability to provide consistent performance without getting tired and their lower susceptibility to harsh weather conditions compared to humans. Thus, a coordinated team of robots that can assist human SAR personnel by autonomously performing searches in WiSAR scenarios would be of great value. However, to date, a suitable multi-robot coordination methodology for autonomous search that can satisfactorily address the issues relevant to WiSAR is lacking. The objective of this Dissertation is, thus, to develop a methodology that can autonomously coordinate the search strategy of a multi-robot team in wilderness environments to locate a moving target that is neither continuously nor intermittently observed during the search process. Three issues in particular are addressed: (i) target-location prediction, (ii) robot deployment, and (iii) robot-path planning. The corresponding solution approaches devised to address these issues incorporate the influence of varying terrain that may contain a priori known and unknown obstacles, and deal with unique target physiology and psychology as well as found clues left behind by the target. The solution methods for these three tasks work seamlessly together resulting in a tractable MRC methodology for autonomous robotic WiSAR. Comprehensive simulations have been performed that validate the overall proposed methodology. Moreover, the tangible benefits provided by this methodology were further revealed through its comparison with an alternative search method.
13

Mobile robot for search and rescue

Litter, Jansen J. January 2004 (has links)
Thesis (M.S.)--Ohio University, June, 2004. / Title from PDF t.p. Includes bibliographical references (leaves 98-100).
14

A see-ability metric to improve mini unmanned aerial vehicle operator awareness using video georegistered to terrain models /

Engh, Cameron Howard, January 2008 (has links) (PDF)
Thesis (M.S.)--Brigham Young University. Dept. of Computer Science, 2008. / Includes bibliographical references (p. 101-107).
15

Multi-modal people detection from aerial video

Flynn, Helen January 2015 (has links)
There has been great interest in the use of small robotic helicopter vehicles over the last few years. Although there are regulatory issues involved in flying these that are still to be solved, they have the potential to provide a practical mobile aerial platform for a small fraction of the cost of a conventional manned helicopter. One potential class of applications for these is in searching for people, and this thesis explores a new generation of cameras which are suitable for this purpose. We propose HeatTrack, a novel algorithm to detect and track people in aerial imagery taken from a combined infrared/visible camera rig. A Local Binary Patterns (LBP) detector finds silhouettes in the infrared image which are used guide the search in the visible light image, and a Kalman filter combines information from both modalities in order to track a person more accurately than if only a single modality were available. We introduce a method for matching the thermal signature of a person to their corresponding patch in the visible modality, and show that this is more accurate than traditional homography-based matching. Furthermore, we propose a method for cancelling out camera motion which allows us to estimate a velocity for the person, and this helps in determining the location of a person in subsequent frames. HeatTrack demonstrates several advantages over tracking in the visible domain only, particularly in cases where the person shows up clearly in infrared. By narrowing down the search to the warmer parts of a scene, the detection of a person is faster than if the whole image were searched. The use of two imaging modalities instead of one makes the system more robust to occlusion; this, in combination with estimation of the velocity of a person, enables tracking even when information is lacking in either modality. To the best of our knowledge, this is the first published algorithm for tracking people in aerial imagery using a combined infrared/visible camera setup.
16

Impacts of cleanser, material type, methods for cleaning and training on canine decontamination

Powell, Ellie B 01 May 2018 (has links)
Search-and -rescue (SAR) teams spend days and sometimes weeks in the field following a disaster. After completing their assigned mission, handlers and canines return to base, potentially bringing contaminated material with them. There were 3 objectives for this study; (1) the effects of cleanser and equipment materials on the efficiency of decontamination protocols, (2) the effects of improved treatments on the efficiency of decontamination protocols and (3) the use of field kits and improved training on decontamination techniques in the field. In the first study, straps (n = 54) were cut from biothane, leather and nylon. Straps were washed with three kinds of cleansers; Dawn dishwashing detergent, Johnson and Johnson’s Head-to-toe baby wash and Simple Green. In addition, three different types of treatments: 5-minute soak (A), double 5-minute soak (B) and a 3-minute soak with a 2-minute agitation (C). In the second study, straps (n = 40) of leather and nylon were utilized. Unlike the previous study, only Dawn dishwashing detergent and Johnson and Johnson’s Head-To-Toe-Baby Wash were selected as cleansers for decontamination. In addition, improved treatments (PW or SK) were created and utilized to further decontaminant the straps. The finally part of the study utilized canine teams (n = 10), composed of canine and handlers and were randomly assigned to one of two groups. Groups were structured as follows: TRAINED (n = 5) received 30-minutes of interactive training (using the illustrated guide contained in the kit) on proper utilization of equipment provided; UNTRAINED (n = 5) received the same field kit and an illustrated guide with no interactive training. An oil-based pseudocontaminant (GloGerm®) was topically applied to the straps in the first two studies and then to four anatomic sites on the canine participants: cranial neck, between the shoulder blades, left medial hindlimb and hind left paw in the last study. Pre- and post-images were taken of the straps and at the four anatomical locations prior to and following decontamination. Images were analyzed via two methods 1) categorical scores; 2) measured fluorescent reduction. Categorical scores were assigned, using two blinded reviewers (Venable et. al., 2017). The categorical scores were allotted as follows: 0 = <24% contaminant reduction; 1 = 25-50% contaminant reduction; 2 = 51-75% contaminant reduction; and 3 = >76% contaminant reduction (Lee et al., 2014). No score discrepancies >1 were observed between reviewers. Score data were analyzed using SAS version 9.4 (SAS Institute Inc., Cary, NC), as a Chi Square with PROC FREQ and measurement data were analyzed using PROC ANOVA. Results in the first study indicate that material (P = .2331), cleanser (P = .2156) and treatment (P = .9139) had no effect on contaminant reduction. However, when treatments were improved in the second study, power wash was more effective at contaminant reduction (P = .0004). In addition, material was also determined to have an effect on decontamination (P = .0135). Although, the kind of cleanser used had no effect (P = .3564). Additionally, in the last study, TRAINED handlers were more effective at contamination reduction (P = .0093) as compared to their UNTRAINED counterparts. The initial results indicate that no combination of material, cleanser or treatment had any effect on reducing the oil-based contaminants. Nevertheless, with improved treatments there is a potential to more thoroughly decontaminate the collars and leashes. In addition, study three indicates that handlers, when properly trained, can achieve reduction of oil-based contaminants with a basic field kit and a garden hose. These data have implications for management of canines in the field that may be exposed to unknown substances and require timely decontamination.
17

Task Scheduling Using Rasmussen's 1983 Skills, Rules, and Knowledge Framework to Maximize Mission Efficiency

Badger, Madeline Victoria 06 June 2024 (has links)
Search and Rescue (SAR) operations are necessary during times of natural disaster or when individuals go missing. These missions mobilize individuals, both paid and volunteer, to find lost persons and are often carried out in treacherous areas. It is important for teammates to be focused and prepared. Specifically, the search coordinator's role and the head of command directing their teammates is vital to the outcome of a SAR mission. Their workload is significant, however, inviting the opportunity for autonomy to work in tandem with the search coordinator to ensure optimal, timely decisions are made for task scheduling. There has been a significant amount of investigation into task scheduling for human-autonomy teams, but there is a gap in the ordering methods used. One possible framework to investigate uses Rasmussen's SRK framework to classify individual responses to assigned tasks. There is also a significant body of work on this framework, but very little in a proactive task scheduling context. This thesis proposes a new approach to task scheduling utilizing Rasmussen's SRK framework. Scheduling tasks in this manner allows the characteristics of the tasks themselves to be considered as well as a more streamlined approach to reducing overall cognitive load for SAR teammates. An experimental study was conducted to determine the effectiveness of the proposed task scheduling methods based on the SRK framework. Initial results suggest there is an impact on scheduling tasks with respect to SRK, but further investigation is warranted to determine more specific factors. / Master of Science / Search and Rescue (SAR) operations are necessary during times of natural disaster or when individuals go missing. These missions mobilize individuals, both paid and volunteer, to find lost persons and are often carried out in treacherous areas. It is important for teammates to be focused and prepared. Specifically, the search coordinator's role and the head of command directing their teammates is vital to the outcome of a SAR mission. They have a significant number of responsibilities, however, inviting the potential for becoming overloaded with information and decisions. This does, however, suggest a significant opportunity for autonomy to work in tandem with the search coordinator to ensure optimal, timely decisions are made for task scheduling. There has been a significant amount of investigation into task scheduling for human-autonomy teams, but there is a gap in the ordering methods used. One possible framework to use to fill this gap is Rasmussen's Skill-Rule-Knowledge (SRK) framework to categorize and predict how individuals will respond to their assigned tasks. There is also a significant body of work on this framework, but very little in a proactive task scheduling context. This thesis proposes a new approach to task scheduling utilizing Rasmussen's SRK framework. Scheduling tasks in this manner allows the characteristics of the tasks themselves to be considered. In addition, the possibility of overwhelming SAR team members can be reduced by scheduling tasks intelligently. An experimental study was conducted to determine the effectiveness of the proposed task scheduling methods based on the SRK framework. Initial results suggest there is an impact on scheduling tasks with respect to SRK, but further investigation is warranted to determine more specific factors.
18

Transparency, trust, and level of detail in user interface design for human autonomy teaming

Wang, Tianzi 03 November 2023 (has links)
Effective collaboration between humans and autonomous agents can improve productivity and reduce risks of human operators in safety-critical situations, with autonomous agents working as complementary teammates and lowering physical and mental demands by providing assistance and recommendations in complicated scenarios. Ineffective collaboration would have drawbacks, such as risks of being out-of-the-loop when switching over controls, increased time and workload due to the additional needs for communication and situation assessment, unexpected outcomes due to overreliance, and disuse of autonomy due to uncertainty and low expectations. Disclosing the information about the agents for communication and collaboration is one approach to calibrate trust for appropriate reliance and overcome the drawbacks in human-autonomy teaming. When disclosing agent information, the level of detail (LOD) needs careful consideration because not only the availability of information but also the demand for information processing would change, resulting in unintended consequences on comprehension, workload, and task performance. This dissertation investigates how visualization design at different LODs about autonomy influences transparency, trust, and, ultimately, the effectiveness of human autonomy teaming (HAT) in search and rescue missions. LOD indicates the amount of information aggregated or organized in communication for the human to perceive, comprehend, and respond, and could be manipulated by changing the granularity of information in a user interface. High LOD delivers less information so that users can identify overview and key information of autonomy, while low LOD delivers information in a more detailed manner. The objectives of this research were (1) to build a simulation platform for a representative HAT task affected by visualizations at different LODs about autonomy, (2) to establish the empirical relationship between LOD and transparency, given potential information overload with indiscriminate exposure, and (3) examine how to adapt LOD in visualization with respect to trust as users interact with autonomy over time. A web-based application was developed for wilderness SAR, which can support different visualizations of the lost-person model, UAV path-planner, and task assignment. Two empirical studies were conducted recruiting human participants to collaborate with autonomous agents, making decisions on search area assignment, unmanned aerial vehicle path planning, and object detection. The empirical data included objective measures of task performance and compliance, subjective ratings of transparency, trust, and workload, and qualitative interview data about the designs with students and search and rescue professionals. The first study revealed that lowering LODs (i.e., more details) does not lead to a proportional increase in transparency (ratings), trust, workload, accuracy, and speed. Transparency increased with decreased LODs up to a point before the subsequent decline, providing empirical evidence for the transparency paradox phenomenon. Further, lowering LOD about autonomy can promote trust with diminishing returns and plateau even with lowering LOD further. This suggests that simply presenting some information about autonomy can build trust quickly, as the users may perceive any reasonable forms of disclosure as signs of benevolence or good etiquette that promote trust. Transparency appears more sensitive to LOD than trust, likely because trust is conceptually less connected to the understanding of autonomy than transparency. In addition, the impacts of LODs were not uniform across the human performance measurements. The visualization with the lowest LOD yielded the highest decision accuracy but the worst in decision speed and intermediate levels of workload, transparency, and trust. LODs could induce the speed-accuracy trade-off. That is, as LOD decreases, more cognitive resources are needed to process the increased amount of information; thus, processing speed decreases accordingly. The second study revealed patterns of overall and instantaneous trust with respect to visualization at different LODs. For static visualization, the lowest LOD resulted in higher transparency ratings than the middle and high LOD. The lowest LOD generated the highest overall trust amongst the static and adaptive LODs. For visualizations of all LODs, instantaneous trust increased and then stabilized after a series of interactions. However, the rate of change and plateau for trust varied with LODs and modes between static and adaptive. The lowest, middle, and adaptive LODs followed a sigmoid curve, while the high LOD followed a linear one. Among the static LODs, the lowest LOD exhibits the highest growth rate and plateau in trust. The middle LOD developed trust the slowest and reached the lowest plateau. The high LOD showed a linear growth rate until a level similar to that of the lowest LOD. Adaptive LOD earned the trust of the participants at a very similar speed and plateau as the lowest LOD. Taking these results together, more details about autonomy are effective for expediting the process of building trust, as long as the amount of information is carefully managed to prevent overloading participants' information processing. Further, varying quantities of information in adaptive mode could yield very similar growth and plateau in trust, helping humans to deal with either the minimum or maximum amount of information. This adaptive approach could prevent situations where comprehension is hindered due to insufficient information or where users are potentially overloaded by details. Adapting LODs to instantaneous trust presents a promising technique for managing information exchange that can promote the efficiency of communication for building trust. The contribution of this research to literature is two-fold. The first study provides the first empirical evidence indicating that the impact of LODs on transparency and trust is not linear, which has not been explicitly demonstrated in prior studies about HAT. The impact of LOD on transparency is more sensitive than trust, calling for a more defined and consistent use of the term or concept - "transparency" and a deeper investigation into the relationships between trust and transparency. The second study presents the first examination of how static and dynamic LODs can influence the development of trust toward autonomy. The algorithm for adapting LOD for the adaptive visualization based on user trust is novel, and adaptive LODs in visualization could switch between detailed and abstract information to influence trust without always transmitting all the details about autonomy. Visualizations with different LODs in both static and adaptive modes present their own set of benefits and drawbacks, resulting in trade-offs concerning the speed of promoting trust and information quantity transmitted during communication. These findings indicate that LOD is an important factor for designing and analyzing visualization for transparency and trust in HAT. / Doctor of Philosophy / The collaboration between human and autonomous agents in search and rescue (SAR) missions aims to improve the success rate and speed of finding the lost person. In these missions, a human supervisor may coordinate with autonomous agents responsible for estimating lost person behavior, path planning, and unmanned aerial vehicles. The human SAR professional may rely on information from the autonomous agents to reinforce the search plan and make crucial decisions. Balancing the amount of information provided by the autonomous agents to the SAR professionals is critical, as insufficient information can hinder trust, leading to manual intervention, and excessive information can cause information overload, reducing efficiency. Both cases can result in human distrust of autonomy. Effective visualization of information can help study and improve the transmission of information between humans and autonomous agents. This approach can reduce unnecessary information in communication, thus conserving communication resources without sacrificing trust. This dissertation investigates how visualization design at the proper aggregation of details about autonomy, also referred to as level of detail (LOD), influences perceived understanding of the autonomous agents (i.e., transparency), trust, and ultimately, the effectiveness of human autonomy teaming (HAT) for wilderness SAR. A simulation platform was built for proof-of-concept, and two studies were conducted recruiting human participants to use the platform for completing simulated SAR tasks supported by visualizations at different LODs about autonomy. Study 1 results showed that transparency ratings increased with more details about autonomy up to a point and then declined with the most details (i.e., lowest LOD). Trust, workload, and performance also did not linearly improve with more details about autonomy. The non-linear relationships of LODs with transparency, trust, workload, and performance, confirmed the phenomenon of the transparency paradox, which refers to the disclosure of excessive information about autonomy may hinder transparency and subsequent performance. Study 2 results also illustrated that when visualization with LOD adapted to instant trust, the speed of building trust and the plateau of trust on autonomy can achieve the same level as the visualization provided with the most details, which performed the best in building trust. This adaptive approach minimized the amount of information displayed relative to the visualization, constantly presenting the most information, potentially easing the burden of communication. Taken together, this research highlights that the amount of information about autonomy to display must be considered carefully for both research and practice. Further, this dissertation advances the visualization design by illustrating that visualization adapting LODs based on trust is effective at building trust in a manner that minimizes the amount of information presented to the user.
19

Svensk undsättningsförmåga

Wärja, Andreas January 2009 (has links)
<p>I takt med att Försvarsmakten ökar sitt internationella engagemang ökar också riskerna för att svensk personal ska bli isolerad, tillfångatagen eller kidnappad. Syftet med den här uppsatsen är att undersöka om svensk undsättningsförmåga är tillräcklig för de insatser som Försvarsmakten genomför internationellt.</p><p>Det kan konstateras att flera faktorer bidrar till ett behov av en undsättningsförmåga. Försvarsmakten har en moralisk skyldighet mot sin personal att göra allt för att se till att de kommer hem ifall något skulle hända dem. Försvarsmakten har heller inte råd att få personal kidnappad då det genom media och hemmaopinion kan ge ett högt tryck på politiker vilket i sin tur kan leda till att Försvarsmakten tvingas dra sig ur en insats. Förvarsmakten måste även kunna ansvara för sig själv och inte förlita sig på att en annan nation ska lösa problemet när situationen inte kan hanteras. I övriga europeiska länder saknas i många fall en fullgod undsättningsförmåga och därför blir det än viktigare att Försvarsmakten innehar en egen förmåga. Förmågan bör åtminstone omfatta kvalificerade helikoptrar och välutbildade undsättningsenheter med rätt utrustning för att en trovärdig undsättningsförmåga ska finnas i organisationen.</p><p>Resultaten av uppsatsen tyder på att Försvarsmakten har kommit långt i sin strävan att utveckla en undsättningsförmåga men att organisationen brister i att utveckla verkligt kvalificerade undsättningsförband. Dessa förband bör tilldelas mer resurser för att en trovärdig förmåga kopplat mot Försvarsmaktens målsättning ska upprätthållas.</p> / <p>When the Swedish Armed Forces are increasing its contribution to international peacekeeping missions there is an increasing danger that Swedish personnel could find themselves isolated and taken hostage. The purpose with this work is to examine whether the level of Swedish Personnel Recovery is acceptable due to the international missions the Swedish Armed Forces is participating in. </p><p>The Swedish Armed Forces has the moral responsibility to bring all personnel home when deployed. One reason to have Personnel Recovery capability is to reduce the danger of getting personnel executed and media exploiting it which could lead to a withdrawal from the area. Further on Swedish Armed Forces have got to have its own Personnel Recovery capability since not very many countries has a sufficient capability. The Swedish Armed Forces Personnel Recovery capability should at least contain qualified helicopters and Personnel Recovery units.</p><p>The results of this work is that the Swedish Armed Forces has made huge progress in developing a Personnel Recovery capability although there is a lack of truly qualified Personnel Recovery units which should be given sufficient funds to enhance the Swedish Personnel Recovery capability.</p>
20

Svensk undsättningsförmåga

Wärja, Andreas January 2009 (has links)
I takt med att Försvarsmakten ökar sitt internationella engagemang ökar också riskerna för att svensk personal ska bli isolerad, tillfångatagen eller kidnappad. Syftet med den här uppsatsen är att undersöka om svensk undsättningsförmåga är tillräcklig för de insatser som Försvarsmakten genomför internationellt. Det kan konstateras att flera faktorer bidrar till ett behov av en undsättningsförmåga. Försvarsmakten har en moralisk skyldighet mot sin personal att göra allt för att se till att de kommer hem ifall något skulle hända dem. Försvarsmakten har heller inte råd att få personal kidnappad då det genom media och hemmaopinion kan ge ett högt tryck på politiker vilket i sin tur kan leda till att Försvarsmakten tvingas dra sig ur en insats. Förvarsmakten måste även kunna ansvara för sig själv och inte förlita sig på att en annan nation ska lösa problemet när situationen inte kan hanteras. I övriga europeiska länder saknas i många fall en fullgod undsättningsförmåga och därför blir det än viktigare att Försvarsmakten innehar en egen förmåga. Förmågan bör åtminstone omfatta kvalificerade helikoptrar och välutbildade undsättningsenheter med rätt utrustning för att en trovärdig undsättningsförmåga ska finnas i organisationen. Resultaten av uppsatsen tyder på att Försvarsmakten har kommit långt i sin strävan att utveckla en undsättningsförmåga men att organisationen brister i att utveckla verkligt kvalificerade undsättningsförband. Dessa förband bör tilldelas mer resurser för att en trovärdig förmåga kopplat mot Försvarsmaktens målsättning ska upprätthållas. / When the Swedish Armed Forces are increasing its contribution to international peacekeeping missions there is an increasing danger that Swedish personnel could find themselves isolated and taken hostage. The purpose with this work is to examine whether the level of Swedish Personnel Recovery is acceptable due to the international missions the Swedish Armed Forces is participating in.  The Swedish Armed Forces has the moral responsibility to bring all personnel home when deployed. One reason to have Personnel Recovery capability is to reduce the danger of getting personnel executed and media exploiting it which could lead to a withdrawal from the area. Further on Swedish Armed Forces have got to have its own Personnel Recovery capability since not very many countries has a sufficient capability. The Swedish Armed Forces Personnel Recovery capability should at least contain qualified helicopters and Personnel Recovery units. The results of this work is that the Swedish Armed Forces has made huge progress in developing a Personnel Recovery capability although there is a lack of truly qualified Personnel Recovery units which should be given sufficient funds to enhance the Swedish Personnel Recovery capability.

Page generated in 0.0735 seconds