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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.
201

XMARCUS: A Pathway Towards Remote Robotic Surgery Coaching

Nelson, Gunnar Beck 22 June 2022 (has links)
XMARCUS: A Pathway Towards Remote Robotic Surgery Training}, is a compilation work of human-robot, human-artificial intelligence, and human-computer interaction. The thesis provides a technical overview of the history of robotic surgery, present innovation, and future impacts. We present a behaviorist overview and describe our view of the overall direction of robotic surgery to enhance surgical training. We also discuss application towards future directions of translational medicine, adoption of surgical tools, and innovation within medicine. XMARCUS indicates the possibility of another artificial intelligence winter within surgery domain and presents a direction towards surgical training. Our macroscopic perspective and development of demo applications on third-party consoles demonstrates how to enhance robotic surgery training, provide future directions of minimally invasive surgery, and further enhance medical education. We also present the argument for a definitive direction of applications of artificial intelligence, the breakdown of its very definition, along with its proper application, in order to connect both the surgical and software communities for further steps in translational medicine. XMARCUS is not only a pathway towards applicable accessibility for surgical training, but also is a framework to allow further innovation in translational medicine for robotic surgery. The thesis consists of 14 chapters divided into 3 parts. Part 1 provides a technical history background focused on the history of robotic surgery, the present hardware breakdown, applications and advancement of artificial intelligence and computer vision practices within the field. Part 2 highlights the disconnect between both surgical and software communities, and a pathway to integrating both fields towards translational medicine, specifically focusing on artificial intelligent practices by integrating machine learning for computer vision in the endoscopic space. Part 3 presents future research directions and important research questions to address, highlighting the future of surgery with the lack of physician accessibility to implementing artificial intelligence practices, focuses on providing an integration of remote robotic surgery training. / Master of Science / XMARCUS: A Pathway Towards Remote Robotic Surgery Training} is an avocation, proof of concept, and general overview of robotic surgery, its present predicament, and future impact of software engineering. There is an ever pressing need to integrate artificial intelligence practices within robotic surgery and minimally invasive surgery procedures. However, computing has faced a number of artificial intelligence winters with no viable means of application. Due to the lack of available data and machine learning models trained on such data, there is another permanence of an artificial intelligence winter, especially surgical applications. We also present the XMARCUS dataset, with over 12,000 images and a walk-through for crowdsource annotation process using Intel's OpenVino framework, where there has been less viable data. The focus is on the general overview of artificial intelligence, within the domain of machine learning for computer vision practices. This includes a discussion of virtual coaching and remote surgical training, specifically methods to further develop robotic surgery simulation software, in order to advance not solely the endoscopic space, but also the surgical training. Human-computer interaction models and theories, such as the Diffusion of Innovation, showcase the adaptation and timing of certain technologies, for viable application. We also present another concept focusing on the timing of technology to be introduced to help with translational medicine. Finally, we show an application in a series of proof concepts of remote virtual coaching for remote robotic surgical training including the psychomotor skills and FDA policy overview for implementing novel software practices to advance robotic surgery. With consideration towards remote surgery training and the universal push for creating credentialing and guidelines in robotic surgery, we discuss further disparities to showcase an ethical framework to enhance surgical training and implement novel software engineering practices.
202

Development of Intelligent Exoskeleton Grasping Through Sensor Fusion and Slip Detection

Lee, Brielle January 2018 (has links)
This thesis explores the field of hand exoskeleton robotic systems with slip detection and its applications. It presents the design and control of the intelligent sensing and force- feedback exoskeleton robotic (iSAFER) glove to create a system capable of intelligent object grasping initiated by detection of the user’s intentions through motion amplification. Using a combination of sensory feedback streams from the glove, the system has the ability to identify and prevent object slippage, as well as adapting grip geometry to the object properties. The slip detection algorithm provides updated inputs to the force controller to prevent an object from being dropped, while only requiring minimal input from a user who may have varying degrees of functionality in their injured hand. This thesis proposes the use of a high dynamic range, low cost conductive elastomer sensor coupled with a negative force derivative trigger that can be leveraged in order to create a controller that can intelligently respond to slip conditions through state machine architecture, and improve the grasping robustness of the exoskeleton. The mechanical and electrical improvements to the previous design, the sensing and force- feedback exoskeleton robotic (SAFER) glove, are described while details of the controller design and the proposed assistive and rehabilitative applications are explained. Experimental results confirming the validity of the proposed system are also presented. In closing, this thesis concludes with topics for future exploration. / Master of Science / Exoskeletons are robotic systems that have rigid external covering, such as links, joints, and/or soft artificial tendons or muscles, for the desired body part to provide support and/or protection. These are typically used to enhance power and strength, provide rehabilitation and assistance, and teleoperate other robots from a distance. While the US Army developed exoskeletons for strengthening purposes, another potential purpose of exoskeletons, which is serving medical needs, such as rehabilitation, attracted a lot of attention. Among numerous illnesses and injuries that may lead to impaired hand functionality, the U.S. Department of Health and Human Services estimated that approximately 470,000 people survive strokes every year in the United States and require continuous rehabilitation to recover their motor functions. Though medical professionals believe that the intensity and duration of rehabilitation is the key for maximizing the rate of recovery, it is often limited due to many reasons, such as cost or difficulty in attending rehabilitation sessions. To augment the availability and quality of rehabilitation, the study of exoskeletons has earned popularity. Beyond the capability of providing simple movements, such as passive rehabilitation, many scientists researched to provide active rehabilitation, which involves active participation from the patients. Furthermore, detecting the patient’s intention to activate the rehabilitation glove became a topic of interest, and many types of sensors were utilized in research. This thesis explores the design and control of the intelligent sensing and force- feedback exoskeleton robotic (iSAFER) glove, which detects the user’s intentions to activate the system through motion amplification. The iSAFER glove performs soft initial grasp until the fingers touch an object. After the object is gently grabbed and lifted, the grasp is autonomously adjusted through slip detection until there is no more slip. To facilitate this idea, a low cost force sensor was created and leveraged to improve the grasping control of the exoskeleton. The mechanical and electrical improvements to the previous design, the sensing and force-feedback exoskeleton robotic (SAFER) glove, are described while details of the controller design and the proposed assistive and rehabilitative applications are explained. Experimental results confirming the validity of the proposed system are also presented. In closing, this thesis concludes with topics for future exploration.
203

Traction Control Study for a Scaled Automated Robotic Car

Morton, Mark A. 01 June 2004 (has links)
This thesis presents the use of sliding mode control applied to a 1/10th scale robotic car to operate at a desired slip. Controlling the robot car at any desired slip has a direct relation to the amount of force that is applied to the driving wheels based on road surface conditions. For this model, the desired traction/slip is maintained for a specific surface which happens to be a Lego treadmill platform. How the platform evolved and the robot car was designed are also covered. To parameterize the system dynamics, simulated annealing is used to find the minimal error between mathematical simulations and physical test results. Also discussed is how the robot car and microprocessor can be modeled as a hybrid system. The results from testing the robot car at various desired percent slip show that it is possible to control the slip dynamics of a 1/10th scale automated robotic car and thus pave the way for further studies using scaled model cars to test an automated highway system. / Master of Science
204

Development of robotic system for biomass production chamber : mechanism and its dynamic modeling

Patil, Rahul 01 April 2003 (has links)
No description available.
205

Design and Implementation of Articulated Robotic Tails to Augment the Performance of Reduced Degree-of-Freedom Legged Robots

Saab, Wael 24 April 2018 (has links)
This dissertation explores the design, and implementation of articulated robotic tail mechanisms onboard reduced degree-of-freedom (DOF) legged robots to augment performance in terms of stability and maneuverability. Fundamentally, this research is motivated by the question of how to improve the stability and maneuverability of legged robots. The conventional approach to address these challenges is to utilize leg mechanisms that are composed of three or more active DOFs that are controlled simultaneously to provide propulsion, maneuvering, and stabilization. However, animals such as lizards and cheetahs have been observed to utilize their tails to aid in these functionalities. It is hypothesized that by using an articulated tail mechanism to aid in these functionalities onboard a legged robot, the burden on the robot's legs to simultaneously maneuver and stabilize the robot may be reduced. This could allow for simplification of the leg's design and control algorithms. In recent years, significant progress has been accomplished in the field of robotic tail implementation onboard mobile robots. However, the main limitation of this work stems from the proposed tail designs, the majority of which are composed of rigid single-body pendulums that provide a constrained workspace for center-of-mass positioning, an important characteristics for inertial adjustment applications. Inspired by lizards and cheetahs that adjust their body orientation using flexible tail motions, two novel articulated, cable driven, serpentine-like tail mechanisms are proposed. The first is the Roll-Revolute-Revolute Tail which is a 3-DOF mechanism, designed for implementation onboard a quadruped robot, that is capable of forming two mechanically decoupled tail curvatures via an s-shaped cable routing scheme and gear train system. The second is a the Discrete Modular Serpentine Tail, designed for implementation onboard a biped robot, which is a modular two-DOF mechanism that distributes motion amongst links via a multi-diameter pulley. Both tail designs utilize a cable transmission system where cables are routed about circular contoured links that maintain equal antagonistic cable displacements that can produce controlled articulated tail curvatures using a single active-DOF. Furthermore, analysis and experimental results have been presented to demonstrate the effectiveness of an articulated tail's ability to: 1) increase the manifold for center-of-mass positioning, and 2) generate enhanced inertial loading relative to conventionally implemented pendulum-like tails. In order to test the tails ability to augment the performance of legged robots, a novel Robotic Modular Leg (RML) is proposed to construct both a reduced-DOF quadrupedal and bipedal experimental platform. The RML is a modular two-DOF leg mechanism composed of two serially connected four-bar mechanisms that utilizes kinematic constraints to maintain a parallel orientation between it's flat foot and body without the use of an actuated ankle. A passive suspension system integrated into the foot enables the dissipation of impact energy and maintains a stable four point-of-contact support polygon on both flat and uneven terrain. Modeling of the combined legged robotic systems and attached articulated tails has led to the derivation of dynamic formulations that were analyzed to scale articulated tails onboard legged robots to maximize inertial adjustment capabilities resulting from tail motions and design a control scheme for tail-aided maneuvering. The tail prototypes, in conjunction with virtual simulations of the quadruped and biped robot, were used in experiments and simulations to implement and analyze the methods for maneuvering and stabilizing the proposed legged robots. Results successfully demonstrate the tails' ability to augment the performance of reduced-DOF legged robots by enabling comparable walking criteria with respect to conventional legged robots. This research provides a firm foundation for future work involving design and implementation of articulated tails onboard legged robots for enhanced inertial adjustment applications. / Ph. D. / In nature, animals commonly use their tails to assist propulsion, stabilization, and maneuvering. However, in legged robotic systems, the dominant research paradigm has been to focus on the design and control of the legs as a means to simultaneously provide propulsion, maneuvering, and stabilization. Fundamentally, this research is motivated by the question of how to improve the stability and maneuverability of legged robots utilizing an articulated tail mechanism. It is hypothesized that by using an articulated tail mechanism to aid in these functionalities onboard a legged robots, the burden on the robot’s legs to simultaneously maneuver and stabilize the robot may be reduced. This could allow for simplification of the leg’s design and control algorithms. This doctoral dissertation addresses this problem statement and hypothesis by proposing two articulated tail mechanisms, R3-RT and DMST, that are uniquely designed to be practically implemented on a reduced DOF quadruped and biped robot, respectively, for tail-aided stabilization and maneuverability. Through analysis and experimentation, it is demonstrated that articulated tails enable enhanced workspace and inertial loading capabilities relative to previously implemented pendulum-like tails while the proposed leg mechanism enables the construction of legged robots with simplified design and control. However, these legged robots cannot effectively walk as standalone machines which justifies the implementation of articulated tails for augmented performance. The dynamics of the combined robotic system consisting of reduced DOF legged robots with implemented tails are derived to scale and optimize articulated tails to maximize inertial adjustment capabilities and derive control schemes for enhanced maneuvering and stabilization using tail-aided motion. Using experiments and simulations, the combined robotic systems consisting of a reduced DOF quadruped and biped robots augmented via articulated tails demonstrate walking criteria that is comparable to conventional legged robots.
206

Factors supporting and constraining the implementation of robot-assisted surgery: a realist interview study

Randell, Rebecca, Honey, S., Alvarado, Natasha, Greenhalgh, J., Hindmarsh, J., Pearman, A., Jayne, D., Gardner, Peter, Gill, A., Kotze, A., Dowding, D. 04 March 2020 (has links)
Yes / To capture stakeholders’ theories concerning how and in what contexts robot-assisted surgery becomes integrated into routine practice. A literature review provided tentative theories that were revised through a realist interview study. Literature-based theories were presented to the interviewees, who were asked to describe to what extent and in what ways those theories reflected their experience. Analysis focused on identifying mechanisms through which robot-assisted surgery becomes integrated into practice and contexts in which those mechanisms are triggered. Nine hospitals in England where robot-assisted surgery is used for colorectal operations. Forty-four theatre staff with experience of robot-assisted colorectal surgery, including surgeons, surgical trainees, theatre nurses, operating department practitioners and anaesthetists. Interviewees emphasised the importance of support from hospital management, team leaders and surgical colleagues. Training together as a team was seen as beneficial, increasing trust in each other’s knowledge and supporting team bonding, in turn leading to improved teamwork. When first introducing robot-assisted surgery, it is beneficial to have a handpicked dedicated robotic team who are able to quickly gain experience and confidence. A suitably sized operating theatre can reduce operation duration and the risk of de-sterilisation. Motivation among team members to persist with robot-assisted surgery can be achieved without involvement in the initial decision to purchase a robot, but training that enables team members to feel confident as they take on the new tasks is essential. We captured accounts of how robot-assisted surgery has been introduced into a range of hospitals. Using a realist approach, we were also able to capture perceptions of the factors that support and constrain the integration of robot-assisted surgery into routine practice. We have translated these into recommendations that can inform future implementations of robot-assisted surgery.
207

Environment-driven Distributed Evolutionary Adaptation for Collective Robotic Systems / Evolution Artificielle pour la Robotique Collective en Environnement Ouvert

Montanier, Jean-Marc 01 March 2013 (has links)
Cette thèse décrit une partie du travail effectué dans le cadre du projet européen Symbrion 1 . Ce projet vise à la réalisation de tâches complexes nécessitant la coopération de multiples robots dans un cadre de robotique en essaim (au moins 100 robots opérant ensemble). De multiples problèmes sont étudiés par le projet dont : l’auto-assemblage de robots en structures complexes et l’auto-organisation d’un grand nombre de robots afin de réaliser une tâche commune. Le principal sujet porte sur les mécanismes d’auto-adaptation pour la robotique modulaire et en essaim, avec un intérêt pour des capacités de forte coordination et de coopération à l’échelle de l’essaim.Les difficultés rencontrées dans la réalisation de ce projet sont dues à l’utilisation de robots dans des environnements ouverts restant inconnus jusqu’à la phase de déploiement. Puisque les conditions d’opérations ne peuvent être prédites à l’avance, des algorithmes d’apprentissage en ligne doivent être utilisés pour élaborer les comportements utilisés. Lorsqu’un grand nombre de robots sont utilisés, plusieurs considérations doivent être prise en compte : capacité de communication réduite, faible mémoire, faible capacité de calcul. Par conséquent les algorithmes d’apprentissage en ligne doivent être distribués à travers l’essaim.De multiples approches ont déjà été proposées pour faire face aux problèmes posés par l’apprentissage en ligne décentralisé de comportements robotiques, parmi lesquels la robotique probabiliste, l’apprentissage par renforcement, et la robotique évolutionnaire. Cependant, le problème abordé dans le cadre de cette thèse se caractérise par le fait que l’on considère un groupe de robots (en lieu et place d’un seul et unique robot). De plus, dû à la nature ouverte de l’environnement, il n’est pas possible de supposer que l’ingénieur humain ait les connaissances nécessaires pour définir les éléments indispensables aux processus d’apprentissage.Assurer l’intégrité de l’essaim est placé en tant que premier élément d’une feuille de route visant à définir un ensemble d’étapes nécessaires à la réalisation d’une tâche par un groupe de robot dans un environnement ouvert :– Étape 1 : Assurer l’intégrité de l’essaim.– Étape 2 : Maintenir les robots disponibles en tant que service à l’utilisateur.– Étape 3 : Réaliser la tâche définie par l’utilisateur.Dans le cadre de cette thèse nous travaillons à la réalisation de l’étape 1 de cette feuille de route, et assumons l’hypothèse de travail suivante :Hypothèse de travail : Dans un cadre de robotique collective en environnement ouvert, la réalisation d’une tâche définie par l’utilisateur implique tout d’abord un comportement auto-adaptatif.Le sujet de cette thèse est la réalisation de solutions algorithmiques décentralisées pouvant garantir l’in- tégrité d’un essaim de robots en environnement ouvert lorsque un système robotique collectif utilise une communication locale. La principale difficulté à sa résolution est le besoin de prendre en compte l’envi- ronnement. En effet, en fonction de l’environnement courant, les robots peuvent avoir à démontrer une grande variété de comportements à l’échelle globale comme la coopération, la spécialisation, l’altruisme, ou la division du travail.Dans cette thèse nous introduisons et définissons le problème de l’Adaptation Evolutionnaire Distribuée Guidée par l’Environnement. Nous proposons un algorithme pour résoudre ce problem. Cet algorithme a été validé aussi bien en simulation que sur des robots réels. Il a été utilisé pour étudier le problème de l’auto-adaptation dans les environnements suivants :– Environnement où l’émergence de consensus comportementaux est nécessaire.– Environnements où la robustesse face à des changements environnementaux est nécessaires.– Environnements où des comportements altruistes sont nécessaires. / Cette thèse décrit une partie du travail effectué dans le cadre du projet européen Symbrion 1 . Ce projet vise à la réalisation de tâches complexes nécessitant la coopération de multiples robots dans un cadre de robotique en essaim (au moins 100 robots opérant ensemble). De multiples problèmes sont étudiés par le projet dont : l’auto-assemblage de robots en structures complexes et l’auto-organisation d’un grand nombre de robots afin de réaliser une tâche commune. Le principal sujet porte sur les mécanismes d’auto-adaptation pour la robotique modulaire et en essaim, avec un intérêt pour des capacités de forte coordination et de coopération à l’échelle de l’essaim.Les difficultés rencontrées dans la réalisation de ce projet sont dues à l’utilisation de robots dans des environnements ouverts restant inconnus jusqu’à la phase de déploiement. Puisque les conditions d’opérations ne peuvent être prédites à l’avance, des algorithmes d’apprentissage en ligne doivent être utilisés pour élaborer les comportements utilisés. Lorsqu’un grand nombre de robots sont utilisés, plusieurs considérations doivent être prise en compte : capacité de communication réduite, faible mémoire, faible capacité de calcul. Par conséquent les algorithmes d’apprentissage en ligne doivent être distribués à travers l’essaim.De multiples approches ont déjà été proposées pour faire face aux problèmes posés par l’apprentissage en ligne décentralisé de comportements robotiques, parmi lesquels la robotique probabiliste, l’apprentissage par renforcement, et la robotique évolutionnaire. Cependant, le problème abordé dans le cadre de cette thèse se caractérise par le fait que l’on considère un groupe de robots (en lieu et place d’un seul et unique robot). De plus, dû à la nature ouverte de l’environnement, il n’est pas possible de supposer que l’ingénieur humain ait les connaissances nécessaires pour définir les éléments indispensables aux processus d’apprentissage.Assurer l’intégrité de l’essaim est placé en tant que premier élément d’une feuille de route visant à définir un ensemble d’étapes nécessaires à la réalisation d’une tâche par un groupe de robot dans un environnement ouvert :– Étape 1 : Assurer l’intégrité de l’essaim.– Étape 2 : Maintenir les robots disponibles en tant que service à l’utilisateur.– Étape 3 : Réaliser la tâche définie par l’utilisateur.Dans le cadre de cette thèse nous travaillons à la réalisation de l’étape 1 de cette feuille de route, et assumons l’hypothèse de travail suivante :Hypothèse de travail : Dans un cadre de robotique collective en environnement ouvert, la réalisation d’une tâche définie par l’utilisateur implique tout d’abord un comportement auto-adaptatif.Le sujet de cette thèse est la réalisation de solutions algorithmiques décentralisées pouvant garantir l’in- tégrité d’un essaim de robots en environnement ouvert lorsque un système robotique collectif utilise une communication locale. La principale difficulté à sa résolution est le besoin de prendre en compte l’envi- ronnement. En effet, en fonction de l’environnement courant, les robots peuvent avoir à démontrer une grande variété de comportements à l’échelle globale comme la coopération, la spécialisation, l’altruisme, ou la division du travail.Dans cette thèse nous introduisons et définissons le problème de l’Adaptation Evolutionnaire Distribuée Guidée par l’Environnement. Nous proposons un algorithme pour résoudre ce problem. Cet algorithme a été validé aussi bien en simulation que sur des robots réels. Il a été utilisé pour étudier le problème de l’auto-adaptation dans les environnements suivants :– Environnement où l’émergence de consensus comportementaux est nécessaire.– Environnements où la robustesse face à des changements environnementaux est nécessaires.– Environnements où des comportements altruistes sont nécessaires.
208

En kvalitativ förstudie kring automatiseringstekniken Robotic Process Automation inom medelstora verksamheter : Utmaningar, möjligheter och rekommendationer vid implementering av Robotic process automation i medelstora verksamheter / Robotic process automation : Challenges, opportunities and recommendations when implementing Robotic process automation in medium-sized businesses

Flores, Gabriel, Thor, Nils January 2019 (has links)
Allt fler har fått upp ögonen för olika automatiseringstekniker för att underlätta för kunder, anställda och verksamheten. Robotic Process Automation (RPA) är en snabbt framväxande teknologi som automatiserar repetitiva och monotona arbetsprocesser som kan anses vara tidskrävande för anställda. Genom en kvalitativ fallstudie har möjligheter, utmaningar och rekommendationer som kan förekomma vid en implementering av RPA hos medelstora verksamheter som Stora Tunabyggen AB undersökts. Data som samlats in kommer från intervjuer och en dokumentstudie. En kvalitativ dataanalys genomfördes där möjligheter och utmaningar presenteras, sedan genomfördes en SWOT-analys för att finna styrkor och svagheter med RPA. SWOT-analysen användes sedan för att plocka fram rekommendationer för en eventuell implementering. Resultatet visar att det finns positiva såväl som negativa effekter vid en implementering av RPA som ett företag som överväger en implementering bör ha i åtanke. En utmaning med en implementation av RPA är att kartlägga och beskriva processerna som skall automatiseras. Möjligheten med detta är att personalen slipper fokusera på de monotona och repetitiva arbetsuppgifterna. Tunabyggen bör utvärdera hela verksamheten för en implementation av RPA för att få ut bästa möjliga effekt av RPA. En styrka med RPA är minskade mänskliga fel i verksamhetens arbetsprocesser. En av svagheterna med RPA är att det inte finns någon mänsklig kontroll före en arbetsprocess utförs. / More and more people have got their eyes on different automation techniques to make it easier for customers, employees and the business. Robotic Process Automation (RPA) is a rapidly evolving technology that automates repetitive and monotonous business processes that can be considered time consuming for employees. Through a qualitative case study, opportunities, challenges and recommendations that may occur during an implementation of RPA in medium-sized businesses have been investigated, like Stora Tunabyggen AB. The collected data comes from interviews and a document study. A qualitative data analysis was carried out in which opportunities and challenges were presented. Then a SWOT analysis was carried out to find strengths and weaknesses with RPA. The SWOT analysis was then used to present recommendations for a possible implementation. The result shows positive as well as negative effects that medium-sized businesses should be aware of when considering an implementation of RPA. A challenge with an implementation of RPA is to map and describe the processes that can be automated. A possibility is that the staff no longer have to focus on monotonous and repetitive tasks. Tunabyggen should evaluate the entire operation for an implementation of RPA to get the best possible effect from RPA. A strength with RPA is to reduced human error in the business processes of the organisation. One of the weaknesses of RPA is that there is no human control before a work process is performed.
209

Desenvolvimento de um sistema de comunicação baseado em middlewares para aplicações robóticas / Development of a communication architecture based on middleware for robotic applications

Tamashiro, Gabriel 12 February 2014 (has links)
O aumento no número de dispositivos móveis com crescente capacidade de processamento traz como incentivo o desenvolvimento de sistemas distribuídos que possam explorar estas novas tecnologias. Dentro dos sistemas distribuídos, os mecanismos que permitem a troca de dados entre os processos que o constituem, possuem um papel importante para o desempenho da aplicação. Uma abordagem interessante para implementar estes mecanismos é por meio do uso de middlewares. O middleware abstrai as funcionalidades básicas oferecidas pelo sistema operacional e hardware para oferecer serviços de alto nível aos desenvolvedores. Estes serviços permitem aos desenvolvedores se concentrarem somente na lógica interna de suas aplicações, reduzindo também seu custo de manutenção. Incentivado pela necessidade de um mecanismo que garantisse a troca de informações entre as unidades de um sistema autônomo para o gerenciamento de AGVs (Automated Guided Vehicle), desenvolvido pelo grupo de mecatrônica da Universidade de São Paulo, este trabalho propõe uma arquitetura de comunicação baseada em middlewares que é inspirada no paradigma de comunicação RMI (Remote Method Invocation) para suprir a troca de dados necessária por meio do conceito de objetos distribuídos. Para apresentar o uso da IDL (Interface Definition Language) disponibilizada pela arquitetura proposta, uma demonstração de como acrescentar novos serviços à arquitetura é descrita. Para avaliar o desempenho da arquitetura e analisar o comportamento dos serviços oferecidos, testes de tempo de resposta, throughput e disponibilidade foram realizados. Pode-se verificar que a arquitetura proposta, além de apresentar um desempenho satisfatório para a operação do sistema de AGVs, proporcionou uma estrutura que pode ser facilmente adaptada para futuras alterações no projeto sem modificar diretamente as definições da arquitetura de comunicação. / The increase in the process capacity of mobile devices has motivated the development of distributed applications that exploit new technologies. In distributed applications, the mechanisms that enable the exchange of data among the application processes play an important role in their performance. An interesting way to deal with such an exchange is to adopt middleware to handle communication. The middleware abstracts the functionalities provided by the underlying operational system and hardware and offers a set of high-level services, which assist developers in working directly with the logic of the application and reducing its maintenance costs. Motivated by the necessity of a mechanism that ensures the exchange of information among the units of an AGV (Automated Guided Vehicle) system designed by the University of São Paulo, this dissertation develops a communication architecture based on middleware. The architecture is inspired in the RMI (Remote Method Invocation) paradigm to enable the data exchange based on the concept of distributed objects. An IDL (Interface Definition Language) was conceived for the architecture and a demonstration of how new services can be added to the structure was conducted. To validate the performance of the proposed middleware and its services, tests of network response time, throughput and availability were carried out. The architecture showed a satisfactory performance for the operation of the AGV system and provided a structure that can be easily adapted for future changes in the project.
210

Robotic Catheters for Beating Heart Surgery

Kesner, Samuel Benjamin 12 December 2012 (has links)
Compliant and flexible cardiac catheters provide direct access to the inside of the heart via the vascular system without requiring clinicians to stop the heart or open the chest. However, the fast motion of the intracardiac structures makes it difficult to modify and repair the cardiac tissue in a controlled and safe manner. In addition, rigid robotic tools for beating heart surgery require the chest to be opened and the heart exposed, making the procedures highly invasive. The novel robotic catheter system presented here enables minimally invasive repair on the fast-moving structures inside the heart, like the mitral valve annulus, without the invasiveness or risks of stopped heart procedures. In this thesis, I investigate the development of 3D ultrasound-guided robotic catheters for beating heart surgery. First, the force and stiffness values of tissue structures in the left atrium are measured to develop design requirements for the system. This research shows that a catheter will experience contractile forces of 0.5 – 1.0 N and a mean tissue structure stiffness of approximately 0.1 N/mm while interacting with the mitral valve annulus. Next, this thesis presents the catheter system design, including force sensing, tissue resection, and ablation end effectors. In order to operate inside the beating heart, position and force control systems were developed to compensate for the catheter performance limitations of friction and deadzone backlash and evaluated with ex vivo and in vivo experiments. Through the addition of friction and deadzone compensation terms, the system is able to achieve position tracking with less than 1 mm RMS error and force tracking with 0.08 N RMS error under ultrasound image guidance. Finally, this thesis examines how the robotic catheter system enhances beating heart clinical procedures. Specifically, this system improves resection quality while reducing the forces experienced by the tissue by almost 80% and improves ablation performance by reducing contact resistance variations by 97% while applying a constant force on the moving tissue. / Engineering and Applied Sciences

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