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  • 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.
91

The Effect of Videogame Play on Robotic Surgery Skill Acquisition

Tanaka, Alyssa 01 January 2015 (has links)
Robotic surgery uses innovative technology to transcend a surgeon's skills when performing complex procedures. Currently, the only FDA approved robotic system is Intuitive's da Vinci Surgical System. While this system offers many advantages over other minimally invasive techniques, it also introduces a need for specialized training. Virtual reality simulators have emerged as valuable tools for standardized and objective robotic surgery skill training and assessments. In recent years, the idea of using video game technology in surgical education for laparoscopy has also been explored; however few have attempted to make a connection between video game experience and robotic surgical skills. Thus, the current study aims to examine the performance of video gamers in a virtual reality robotic surgery simulator. Furthermore, the video gamers' performance was compared to that of medical students, expert robotic surgeons, and "laypeople." The purpose of this study is to examine the hypothesis that video gamers acquire perceptual and psychomotor skills through video game play, similar to those used by robotic surgeons. Subjects completed a demographic questionnaire and performed three computer-based perceptual tests: a Flanker compatibility task, a subsidizing task, and a Multiple Object Tracking test. Participants then performed two warm-up exercises on the Mimic dV-Trainer to familiarize themselves with the system and eight trials of two core exercises to test their skills. After completing all trials, participants completed a post-questionnaire regarding their experience with the system. Expert video gamers (n=40), medical students (n=24), laypeople (n=42) and expert robotic surgeons (n=16) were recruited. Medical students and gamers were significantly faster than experts in the Flanker Task. The experts were significantly slower than the all other groups in the subsidizing task. Experts scored significantly higher, were significantly more efficient, and were significantly faster than laypeople, medical students, and gamers in the first trial of Ring & Rail 1 and Suture Sponge. In trial eight of Ring & Rail 1, experts scored significantly higher and were more efficient than laypeople. Experts were also significantly faster than all other groups. Experts scored significantly higher than laypeople and gamers in trial Suture Sponge. Experts were significantly more efficient and significantly faster than all other groups. Contrary to prior literature in laparoscopy, this study was unable to validate enhanced abilities of video gamers in a robotic surgery simulator. This study does further demonstrate that the transfer of skills developed through video game play is relevant to the surgical technique. This may be due to the differences of the systems and how the users interact within them. In a society where video games have become an integral past time, it is important to determine the role that video games play in the perceptual and psychomotor development of users. These findings can be generalized to domains outside of medicine that utilize robotic and computer-controlled systems, speaking to the scope of the gamers' abilities and pointing to the capacity within these systems.
92

Extracting Human Strategies for Use in Robotic Assembly

Birkhimer, Craig E. 10 January 2005 (has links)
No description available.
93

Anti-swing Control of a Suspended Varying Load with a Robotic Crane

Halder, Bibhrajit 27 November 2002 (has links)
No description available.
94

Jellyfish Inspired Underwater Systems and Technologies

Smith, Colin Frederick 12 January 2012 (has links)
Unmanned underwater vehicles (UUVs) have long been in use but increasingly there has been a wave of biomimetic robots taking over the duties and functions of traditional vehicles. A robotic jellyfish, inspired by the species Aurelia aurita was developed and characterized. In addition to the body of the main robotic vehicle, supporting technologies were developed including polymeric artificial muscles, hydrogel-based artificial mesoglea, and an inclinometer inspired by the jellyfish statocyst organ. Through multiple versions, the vehicle was able to attain an order of magnitude increase in proficiency from 0.022 s?? to 0.21 s?? and robustness not found in initial prototypes. A polyvinyl alcohol hydrogel reinforced with ferritin nanoparticles was found to accurately mimic the stress and strain characteristics of natural Aurelia mesoglea while maintaining a high water content similar to the animal. In addition, the optical properties were shown to be controlled by water to DMSO ratio. A five layer PPy-Au-PVDF-Au-PPy actuator stored in 0.5M KCl solution actuated at 4 VDC potential and produced an impressive 90% tip deflection. In addition, the rate of change was extremely high at 50% deflection of initial actuator length per second. The artificial jellyfish statocyst was found to produce the required highly linear voltage divider output. This sensor will provide the vehicle with biomimetic self-awareness of its own body position. Future directions are proposed for the biomimetic robotic jellyfish such as on-board power and computing, multi-material mesoglea with a dermal layer, a MEMS-based statocyst, and polymeric muscles with increased force production and time response. / Master of Science
95

Appliance Architecture in the Invisible College: a Pedagogical Text

Grinham, Jonathan Lorne 08 March 2011 (has links)
This thesis presents a pedagogical framework for understanding dynamic Parametricism within the new media culture. As indicated by the title, 'Appliance Architecture in the Invisible College: a Pedagogical Text', this paper will serve two purposes. First, appliance architecture will construct the theoretical framework that will provide the context for the four case studies presented within this thesis: an interview with Rob Ley, designer of the Reef Project; the design and development of the Eclipsis Screen for the Solar Decathlon house, Lumenhaus; the development of an architectural robotics design laboratory, Prototyping in Architectural Robotics for Technology-enriched Education (PARTeE); and workshop > no.1, a physical computing workshop held at the College of Architecture + Urban Studies (CAUS). Second, the invisible college will serve as a pedagogical framework for teaching dynamic Parametricism within appliance architecture. The invisible college will explore the emergent design typologies developed through the PARTeE laboratory's first year and will culminate in the application of the teaching methodologies used for the physical computing workshop. The following serves to establish the architectural discourse within which 'Appliance Architecture in the Invisible College' is embedded. In the broadest sense, this discourse is that of kinetic architecture. The word 'kinetic' is used to denote motion, or the act or process of changing position of over time, where time is the unit of measurement or relativity. The 'appliance' is defined as any consumer object or assembly with embedded intelligence; it does not shy away from the modern connotation of objects such as a coffee maker, refrigerator or iPod. The appliance as an assembly, therefore, presents a part-to-whole relationship that is understood through GWF Hegel's organic unity, which states: 'everything that exists stands in correlation, and this correlation is the veritable nature of every existence. The existent thing in this way has no being in its own, but only in something else, just as the whole would not be what it is but for the existence of its parts, so the parts would not be what they are but for the existence of the whole' (Leddy, 1991). It is this part-to-whole relationship which provides an understanding of the emergent typologies which structure the foundation for learning within the invisible college. / Master of Architecture
96

Design of a Robotic Equine Forelimb for Testing Load-Bearing Rehabilitative Devices

Ruppert, David Strater 03 March 2003 (has links)
Because horses are animals of flight, bone fractures in the horses' limbs are quite common. When foals fracture a bone in their leg, the healthy leg is often compromised. During convalescence, the animal tends to overstress the healthy leg in an attempt to relieve the stress on the injured leg. This results in angular limb deformities, lax tendons, laminitis, and similar problems. These problems could possibly be avoided through a load-bearing device that would relieve the additional weight from the foal's limbs. In order to allow for in-vitro testing of such a load-bearing device, this thesis describes the design, analysis, and procedure of construction of a robotic replica of a foal's limb. In particular, the robotic replica has been designed to replicate all of the anticipated motion of a foal's limb, including walking, shifting weight from one leg to the other, and kicking, for example, using gait-analysis data from an actual horse's gait. From such data, the robotic replica has been designed in IDEAS and analyzed using multibody dynamics simulations code and the finite-element-analysis software ANSYS. To evaluate the function of the robotic replica, a control system was developed to reproduce observed gait characteristics. Comparison of the computer-simulated gait with the observed gait showed that a linear feedback control algorithm resulted in a response adequate for the proposed function. The proposed robotic replica has the potential for aiding in the development of several other bioassistive devices. With minor modifications, the robotic replica could be used to test a device design to transfer load from the cannon bone to the ground for an animal inflicted with laminitis (founder). These possibilities should be investigated in the future. / Master of Science
97

Comparative Analysis of Lightweight Robotic Wheeled and Tracked Vehicle

Johnson, Christopher Patrick 24 May 2012 (has links)
This study focuses on conducting a benchmarking analysis for light wheeled and tracked robotic vehicles. Vehicle mobility has long been a key aspect of research for many organizations. According to the Department of Defense vehicle mobility is defined as, "the overall capacity to move from place to place while retaining its ability to perform its primary mission"[1]. Until recently this definition has been applied exclusively to large scale wheeled and tracked vehicles. With new development lightweight ground vehicles designed for military and space exploration applications, the meaning of vehicle mobility must be revised and the tools at our disposal for evaluating mobility must also be expanded. In this context a significant gap in research is present and the main goal of this thesis is to help fill the void in knowledge regarding small robotic vehicle mobility assessment. Another important aspect of any vehicle is energy efficiency. Thus, another aim of this study is to compare the energy needs for a wheeled versus tracked robot, while performing similar tasks. The first stage of the research is a comprehensive review of the state-of-the-art in vehicle mobility assessment. From this review, a mobility assessment criterion for light robots will be developed. The second stage will be outfitting a light robotic vehicle with a sensor suite capable of capturing relevant mobility criteria. The third stage of this study will be an experimental investigation of the mobility capability of the vehicle. Finally the fourth stage will include quantitative and qualitative evaluation of the benchmarking study. / Master of Science
98

Trajectory Tracking of a Statically-stable Biped with Two Degrees of Freedom

Trout, Joseph Ewell 22 December 2003 (has links)
This research investigates the possibility of controlling a simple biped having two degrees of freedom only. The biped robot walked on large feet. Having large feet enabled the robot to stand on one leg stably. At any time, the robotà ­s center of gravity remained above the area covered by one of the feet. Two servos actuated the two degrees of freedom tilting the robot to the side or moving the legs forward and backward. The biped moved by alternately tilting and striding. Turns were produced by dragging the feet along the ground. As the feet dragged, the friction generated under the feet created a turning moment that rotated the robot. Thus, the robot was able to step and turn on a flat surface. A control algorithm was developed to attempt trajectory tracking with the biped. Trajectories along a surface can be defined in terms of linear and angular velocities. In this research, it was assumed that a high level controller had transformed a desired trajectory into discrete steps of linear and angular velocities. Motion tests showed how various settings of the servos affected the step length and turning angle of the robot. To produce the desired velocities, a program was created to select the servo commands and set the speed parameters. This program applied knowledge of the expected step length and turning angle and performed feedforward control of the velocities. This investigation identified a trajectory tracking scheme that could be used in an observer feedback scenario to achieve accurate control. / Master of Science
99

A Robotic Head Stabilization Device for Post-Trauma Transport

Williams, Adam John 15 August 2018 (has links)
The work presented in this thesis focuses on the design and testing of a casualty extraction robot intended to stabilize the head and neck of an unresponsive person. The employment of robots in dangerous locales such as combat zones or the site of a natural disaster has the potential to help keep first responders out of harm's way as well as to improve the efficiency of search and rescue teams. After a review of robotic search and rescue platforms the Semi-Autonomous Victim Extraction Robot(SAVER) is introduced. The necessity of a device intended to support the head and cervical spine during transport on a rescue robot is then discussed. The kinematic and dynamic analyses of various candidate differential mechanisms intended for the head stabilization device are described, and the chosen mechanism is demonstrated in a proof-of-concept device. Following testing with a simple PID controller, it was determined an advanced feedback controller with disturbance rejection capabilities was required. Linear Active Disturbance Rejection Control (LADRC) was chosen for its effectiveness in rejecting perturbations and handling modeling uncertainties. The performance the proposed LADRC control scheme was compared with PID in simulation and the results are presented. Finally, a prototype of the device was designed and built to validate the functionality of the subsystem, and the results of the corresponding experimentation are discussed. / M. S. / Robots can help to keep first responders and medics out of dangerous situations by performing the rescue operation themselves or by collaborating with the field medic to make the process quicker and more efficient. The work presented in this thesis begins with a review of state-of-the-art rescue robots followed by the a brief description of the design of a Semi-Autonomous Victim Extraction Robot (SAVER) intended to rescue injured and incapacitated people. After the SAVER system is briefly described, the necessity of a device intended to support the head and cervical spine during transport is discussed. The head stabilization subsystem could also be implemented as a standalone device for use by paramedics to help free up valuable time that would otherwise be spent in manually stabilizing the head and neck of the injured person
100

A user interface for a seven degree of freedom surgical robot

Heunis, Jacobus Stephanus 12 1900 (has links)
Thesis (MScEng)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: This thesis describes the process of developing a user interface for a seven degree of freedom (DOF), minimally invasive surgical robot. For the first two main stages of the overall project, completed by previous students, a primary slave manipulator (PSM) and a secondary slave manipulator (SSM) were developed. The stage in this thesis concentrates on creating a joystick that can control the combined movement of the PSM and SSM. Background information on the field of robotic surgery, with specific reference to current systems’ user interfaces, is given and the technical aspects of the PSM and SSM are determined. This is followed by the motivation and main objectives of the thesis. Objectives were divided into the main categories of mechanical design, electronic design, control system design and testing. The mechanical design of the joystick progresses through a concept development stage, before a final seven DOF articulated arm design is presented and evaluated based on engineering specifications. Aluminium is used as the construction material; electromagnetic brakes are specified for each joint, leading to the final assembly, which is a constructed joystick fulfilling all requirements. The electronic design implements magnetic rotary encoders for the joystick’s position and orientation tracking as well as designs of the necessary power and control circuitry to enable correct joystick functioning. The interfacing of the PSM and SSM had to enable successful communication capabilities between the master and the slave. Several necessary adjustments were therefore made to the slave system, after which the joystick and robot were electronically interfaced to provide a direct serial communication line. For control system design, the joystick and robot were modelled according to the Denavit-Hartenberg principle, which allows direct relation between the position and orientation of the respective end effectors on the joystick and robot sides. Forward kinematic equations were then applied to the joystick; the desired position and orientation of the robot end effector were determined, and inverse kinematic equations were applied to these data to establish the robot’s joint variables. This stage ended with the development of two operational modes: one where only the SSM motors are controlled in order for the slave to follow the master’s movements, and the other where the PSM’s motors are controlled separately. The simultaneous control of all robot motors could not be demonstrated due to fundamental mechanical flaws in the PSM and SSM designs. Finally, testing was undertaken to demonstrate movement control of the robot by the joystick. The intuitiveness of the product was also tested successfully. The study ends with the presentation of the conclusions, the main conclusions being the successful development and testing of a joystick that controls the movement of a surgical robot, as well as the achievement of all main thesis objectives. / AFRIKAANSE OPSOMMING: Hierdie tesis beskryf die proses vir die ontwikkeling van ’n gebruikerskoppelvlak vir ’n sewevryheidsgraad-, minimaal indringende chirurgiese robot. In die eerste twee hoofstadia van die algehele projek, voltooi deur ander studente, is ’n primêre slaafmanipuleerder (PSM) en ’n sekondêre slaafmanipuleerder (SSM) ontwikkel. Die stadium in hierdie tesis konsentreer op die skep van ’n stuurstok waarmee die gekombineerde beweging van die PSM en SSM beheer kan word. Agtergrondinligting oor die gebied van robotiese chirurgie word verskaf, met spesifieke verwysing na die gebruikerskoppelvlakke van huidige stelsels, en die spesifikasies van die PSM en SSM word vasgestel. Daarna volg die beweegrede sowel as die belangrikste oogmerke van die projek. Die oogmerke is in die hoofafdelings van meganiese ontwerp, elektroniese ontwerp, beheerstelselontwerp en toetsing verdeel. Die meganiese ontwerp van die stuurstok behels ’n konsepontwikkelingstadium, wat uitloop op ’n finale sewevryheidsgraad-ontwerp, wat dan op grond van ingenieurspesifikasies aangebied en beoordeel word. Aluminium word as boumateriaal gebruik; elektromagnetiese remme word vir elke koppeling gespesifiseer, en die finale samestel is ’n gekonstrueerde stuurstok wat aan alle vereistes voldoen. Die elektroniese ontwerp behels die gebruik van magnetiese draaikodeerders om die stuurstok se posisie en oriëntasie te bepaal, sowel as meganismes met die nodige krag- en beheerstroombaanwerk om die stuurstok reg te laat funksioneer. ’n Koppelvlak tussen die PSM en die SSM moes suksesvolle kommunikasie tussen die meester en die slaaf bewerkstellig. Verskeie nodige aanpassings is dus aan die slaafstelsel aangebring, waarna die stuurstok en robot elektronies gekoppel is om ’n direkte reekskommunikasielyn te skep. Vir beheerstelselontwerp is die stuurstok en robot volgens die Denavit- Hartenberg-beginsel gemodelleer, wat ’n direkte verhouding tussen die posisie en oriëntasie van die onderskeie eindpunt-effektors aan die stuurstok- en robotkant daarstel. Voorwaartse kinematiese vergelykings is daarna op die stuurstok toegepas; die gewenste posisie en oriëntasie van die robotiese eindpunt-effektor is bepaal, waarna terugwaartse kinematiese vergelykings op hierdie data toegepas is om die robot se koppelingveranderlikes te bepaal. Hierdie afdeling word afgesluit met die ontwikkeling van twee bedryfsmodusse: een waar slegs die SSM-motore beheer word sodat die slaaf die meester se bewegings kan navolg, en die ander waar die PSM se motore afsonderlik beheer word. Die gelyktydige beheer van al die robotmotore kon nie getoon word nie weens fundamentele meganiese tekortkominge in die PSM- en SSM-ontwerp. Laastens is ’n toets uitgevoer om die bewegingsbeheer van die robot deur die stuurstok te toon. Die intuïtiwiteit van die produk is ook suksesvol getoets. Die studie sluit af met die projekgevolgtrekkings, waarvan die belangrikste die suksesvolle ontwikkeling en toetsing van ’n stuurstok is wat daarin slaag om die beweging van ’n chirurgiese robot te beheer, sowel as die verwesenliking van alle hoofprojekoogmerke.

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