Dissertations / Theses on the topic 'Underwater manipulator control systems'
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Andresen, Simen. "Underwater Robotics : control of marine manipulator-vehicle systems." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for teknisk kybernetikk, 2014. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-25875.
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For using underwater vehicle-manipulator systems (UVMS) in a challenging envi-ronment, it is important to have a good mathematical description of the systemwhich accounts for disturbances such as ocean currents. The dynamics equation onmatrix form is therefore derived and different properties such as positive definitenessand skew symmetry is obtained. Based on the derived equations, a sliding modecontroller has been designed in order to track trajectories in the configuration spaceof the UVMS. The controller is robust when it comes to uncertainties in dynamicsparameters and uncertainties in ocean current, yielding global asymptotic stabilityas long as the uncertainties are bounded.Furthermore, a kinematic control system has been designed for facilitating humanoperation of a UVMS, by allowing an operator to only control the end effectormotion. The rest of the motion is then resolved through a weighted least-normpseudo inverse solution of the Jacobian matrix, in order to avoid mechanical jointlimits. Moreover, the vehicle’s motion is controlled by an event based algorithm tolimit the motion of the vehicle. This is done by attaching a 3D meshed polygon tothe vehicle frame and check if the end effector is inside or outside this mesh. Themesh then represents the space, relative to the manipulator, were the end effectoris fully dexterous. The vehicle will then be commanded to move only when the endeffector reaches the outside of the meshed polygon.A simulator has been implemented, based on the derived equations. The simula-tions of the UVMS, with the two controllers, yields good tracking results for trackingtrajectories both in the workspace of the end effector and in the configuration spaceof the UVMS.
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Korkmaz, Ozan. "Modeling And Control Of Autonomous Underwater Vehicle Manipulator Systems." Phd thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12615051/index.pdf.
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In this thesis, dynamic modeling and nonlinear control of autonomous underwater vehicle manipulator systems are presented. Mainly, two types of systems consisting of a 6-DOF AUV equipped with a 6-DOF manipulator subsystem (UVMS) and with an 8-DOF redundant manipulator subsystem (UVRMS) are modeled considering hydrostatic forces and hydrodynamic effects such as added mass, lift, drag and side forces. The shadowing effects of the bodies on each other are introduced when computing the hydrodynamic forces. The system equations of motion are derived recursively using Newton&ndashEuler formulation. The inverse dynamics control algorithms are formulated and trajectory tracking control of the systems is achieved by assigning separate tasks for the end effector of the manipulator and for the underwater vehicle. The proposed inverse dynamics controller utilizes the full nonlinear model of the system and consists of a linearizing control law that uses the feedback of positions and velocities of the joints and the underwater vehicle in order to cancel off the nonlinearities of the system. The PD control is applied after this complicated feedback linearization process yielding second order error dynamics. The thruster dynamics is also incorporated into the control system design. The stability analysis is performed in the presence of parametric uncertainty and disturbing ocean current. The effectiveness of the control methods are demonstrated by simulations for typical underwater missions.
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Barbalata, Corina. "Modelling and control of lightweight underwater vehicle-manipulator systems." Thesis, Heriot-Watt University, 2017. http://hdl.handle.net/10399/3279.
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This thesis studies the mathematical description and the low-level control structures for underwater robotic systems performing motion and interaction tasks. The main focus is on the study of lightweight underwater-vehicle manipulator systems. A description of the dynamic and hydrodynamic modelling of the underwater vehicle-manipulator system (UVMS) is presented and a study of the coupling effects between the vehicle and manipulator is given. Through simulation results it is shown that the vehicle’s capabilities are degraded by the motion of the manipulator, when it has a considerable mass with respect to the vehicle. Understanding the interaction effects between the two subsystems is beneficial in developing new control architectures that can improve the performance of the system. A control strategy is proposed for reducing the coupling effects between the two subsystems when motion tasks are required. The method is developed based on the mathematical model of the UVMS and the estimated interaction effects. Simulation results show the validity of the proposed control structure even in the presence of uncertainties in the dynamic model. The problem of autonomous interaction with the underwater environment is further addressed. The thesis proposes a parallel position/force control structure for lightweight underwater vehicle-manipulator systems. Two different strategies for integrating this control law on the vehicle-manipulator structure are proposed. The first strategy uses the parallel control law for the manipulator while a different control law, the Proportional Integral Limited control structure, is used for the vehicle. The second strategy treats the underwater vehicle-manipulator system as a single system and the parallel position/force law is used for the overall system. The low level parallel position/force control law is validated through practical experiments using the HDT-MK3-M electric manipulator. The Proportional Integral Limited control structure is tested using a 5 degrees-of-freedom underwater vehicle in a wave-tank facility. Furthermore, an adaptive tuning method based on interaction theory is proposed for adjusting the gains of the controller. The experimental results show that the method is advantageous as it decreases the complexity of the manual tuning otherwise required and reduces the energy consumption. The main objectives of this thesis are to understand and accurately represent the behaviour of an underwater vehiclemanipulator system, to evaluate this system when in contact with the environment and to design informed low-level control structures based on the observations made through the mathematical study of the system. The concepts presented in this thesis are not restricted to only vehicle-manipulator systems but can be applied to different other multibody robotic systems.
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Elghazaly, Gamal. "Hybrid cable thruster-actuated underwater vehicle manipulator system : modeling, analysis and control." Thesis, Montpellier, 2017. http://www.theses.fr/2017MONTS067.
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L’industrie offshore, pétrolière et gazière est le principal utilisateur des robots sous-marins, plus particulièrement de véhicules télé-opérés (ou ROV, Remotely Operated Vehicle). L'inspection, la construction et la maintenance de diverses installations sous-marines font parties des applications habituelles des ROVs dans l’industrie offshore. La capacité à maintenir un positionnement stable du véhicule ainsi qu’à soulever et déplacer des charges lourdes est essentielle pour certaines de ces applications. Les capacités de levage des ROVs sont cependant limitées par la puissance de leur propulsion. Dans ce contexte, cette thèse présente un nouveau concept d’actionnement hybride constitué de câbles et de propulseurs. Le concept vise à exploiter les fortes capacités de levage des câbles, actionnés par exemple depuis des navires de surfaces, afin de compléter l’actionnement d’un robot sous-marin. Plusieurs problèmes sont soulevés par la nature hybride (câbles et propulseurs) de ce système d'actionnement. En particulier, nous étudions l’effet de l'actionnement supplémentaire des câbles par rapport à un actionnement exploitant uniquement des propulseurs et nous tâchons de minimiser les efforts exercés par ces derniers. Ces deux objectifs sont les principales contributions de cette thèse. Dans un premier temps, nous modélisons la cinématique et la dynamique d'un robot sous-marin actionné à la fois par des propulseurs et des câbles et équipé d'un bras manipulateur. Un tel système possède une redondance cinématique et d'actionnement.. L'étude théorique sur l'influence de l'actionnement supplémentaire par câbles est appuyée par une étude en simulation, comparant les capacités de force d'un système hybride (câbles et propulseurs) à celles d'un système actionné uniquement par des propulseurs. L'évaluation des capacités est basée sur la détermination de l'ensemble des forces disponibles, en considérant les limites des forces d'actionnement. Une nouvelle méthode de calcul est proposée, pour déterminer l'ensemble des forces disponibles. Cette méthode est basée sur le calcul de la projection orthogonale de polytopes et son coût calculatoire est analysé et comparé à celui d'une méthode de l’état de l’art. Nous proposons également une nouvelle méthode pour le calcul de la distribution des forces d'actionnement, permettant d'affecter une priorité supérieure au sous-système d'actionnement par câbles afin de minimiser les efforts exercés par les propulseurs. Plusieurs cas d'études sont proposés pour appuyer les méthodes proposéesThe offshore industry for oil and gas applications is the main user of underwater robots, particularly, remotely operated vehicles (ROVs). Inspection, construction and maintenance of different subsea structures are among the applications of ROVs in this industry. The capability to keep a steady positioning as well as to lift and deploy heavy payloads are both essential for most of these applications. However, these capabilities are often limited by the available on-board vehicle propulsion power. In this context, this thesis introduces the novel concept of Hybrid Cable-Thruster (HCT)-actuated Underwater Vehicle-Manipulator Systems (UVMS) which aims to leverage the heavy payload lifting capabilities of cables as a supplementary actuation for ROVs. These cables are attached to the vehicle in a setting similar to Cable-Driven Parallel Robots (CDPR). Several issues are raised by the hybrid vehicle actuation system of thrusters and cables. The thesis aims at studying the impact of the supplementary cable actuation on the capabilities of the system. The thesis also investigate how to minimize the forces exerted by thrusters. These two objectives are the main contributions of the thesis. Kinematic, actuation and dynamic modeling of HCT-actuated UVMSs are first presented. The system is characterized not only by kinematic redundancy with respect to its end-effector, but also by actuation redundancy of the vehicle. Evaluation of forces capabilities with these redundancies is not straightforward and a method is presented to deal with such an issue. The impact of the supplementary cable actuation is validated through a comparative study to evaluate the force capabilities of an HCT-actuated UVMS with respect to its conventional UVMS counterpart. Evaluation of these capabilities is based on the determination of the available forces, taking into account the limits on actuation forces. A new method is proposed to determine the available force set. This method is based on the orthogonal projection of polytopes. Moreover, its computational cost is analyzed and compared with a standard method. Finally, a novel force resolution methodology is introduced. It assigns a higher priority to the cable actuation subsystem, so that the forces exerted by thrusters are minimized. Case studies are presented to illustrate the methodologies presented in this thesis
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Koch, Christian Ernst Siegfried. "Model Predictive Control for Six Degrees-of-Freedom Station-Keeping of an Underwater Vehicle-Manipulator System." Thesis, KTH, Reglerteknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-220907.
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Underwater robotics are a reliable and ecient mean for exploration and surveysin a submarine environment. Albeit, intervention tasks, e.g. installationand maintenance, require the expansive and hazardous deployment of professionaldivers. Lightweight unmanned underwater vehicles equipped with a multi-degreeof-freedom manipulator, have been proposed as an alternative. However, the controlof these vehicle-manipulator systems is challenging due to their non-linearhigh-dimensional coupled dynamics. The central problem explored in this thesis,is station keeping of an underwater vehicle under the inuence of a moving manipulator.The manipulator is represented by predictable disturbing forces andmoments. The proposed control scheme is a Model Predictive Control (MPC) algorithmwith preview of the disturbances. In simulation, performance of the MPCscheme is evaluated for dierent degrees of knowledge about the disturbances.Results are compared to a classical feedback controller.Undervattensrobotik medför ett pålitligt och effektivt sätt att utforska submarinamiljöer. Lätta obemannade undervattensfarkoster, utrustade med verktyg,har även föreslagits som ett alternativ till professionella dykare för installationoch underhåll under ytan. Styrning av verktygsutrustade farkoster är en utmaningdå de medför högdimensionell olinjär dynamik och korseffekter. Det centralaproblemet som behandlas i det här arbetet är reglering av en undervattensfarkostutrustad med en robotarm, vars rörelser stör farkosten. Robotarmen representerasav störande krafter och moment som går att förutsäga i modellramverket. Denföreslagna styrlagen är modell-prediktiv reglering (MPC) med störningsprediktion.Styrlagen utvärderas i simulering under olika vetskapsnivåer av störsignalen.Resultaten jämförs även med simuleringar där klassisk återkoppling används.
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Lo, Ka Meng. "A novel design of underwater vehicle-manipulator systems for cleaning water pool." Thesis, University of Macau, 2010. http://umaclib3.umac.mo/record=b2494142.
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Braganza, David. "Control techniques for robot manipulator systems with modeling uncertainties." Connect to this title online, 2007. http://etd.lib.clemson.edu/documents/1193079734/.
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Mohamed, Zaharuddin. "Dynamic modelling and control of a flexible manipulator." Thesis, University of Sheffield, 2003. http://etheses.whiterose.ac.uk/15085/.
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This thesis presents investigations into dynamic modelling and control of a flexible manipulator system. The work on dynamic modelling involves finite element and symbolic manipulation techniques. The control strategies investigated include feedforward control using command shaping techniques and combined feedforward and feedback control schemes. A constrained planar single-link flexible manipulator is used as test and verification platform throughout this work. Dynamic model of a single-link flexible manipulator incorporating structural damping, hub inertia and payload is developed using the finite element method. Experiments are performed on a laboratory-scale single-link flexible manipulator with and without payload for verification of the developed dynamic model. Simulated and experimental system responses to a single-switch bang-bang torque input are presented in the time and frequency domains. Resonance frequencies of the system for the first three modes are identified. The performance and accuracy of the simulation algorithm are studied in comparison to the experimental results in both domains. The effects of damping and payload on the dynamic behaviour of the manipulator are addressed. Moreover, the impact of using higher number of elements is studied. The application of a symbolic manipulation approach for modelling and performance analysis of a flexible manipulator system is investigated. System transfer function can be retained in symbolic form using this approach and good approximation of the system transfer function can be obtained. Relationships between system characteristics and parameters such as payload and hub inertia are accordingly explored. Simulation and experimental exercises are presented to demonstrate the effectiveness of the symbolic approach in modelling and simulation of the flexible manipulator system. Simulation and experimental investigations into the development of feedforward control strategies based on command shaping techniques for vibration control of flexible manipulators are presented. The command shaping techniques using input shaping, low-pass and band-stop filters are considered. The command shaping techniques are designed based on the parameters of the system obtained using the unshaped bang-bang torque input. ii Abstract Performances of the techniques are evaluated in terms of level of vibration reduction, time response specifications, robustness to error in natural frequencies and processing times. The effect of using higher number of impulses and filter orders on the system performance is also investigated. Moreover, the effectiveness of the command shaping techniques in reducing vibrations due to inclusion of payload into the system is examined. A comparative assessment of the performance of the command shaping techniques in vibration reduction of the system is presented. The development of hybrid control schemes for input tracking and vibration suppression of flexible manipulators is presented. The hybrid control schemes based on collocated feedback controllers for rigid body motion control with non-collocated PID control and feedforward control for vibration suppression of the system are examined. The non-collocated PID control is designed utilising the end-point deflection (elastic deformation) feedback whereas feedforward control is designed using the input shaping technique. The developed hybrid schemes are tested within the simulation environment of the flexible manipulator with and without payload. The performances of the control schemes are evaluated in terms of input tracking capability and vibration suppression of the flexible manipulator. Initially, a collocated PD utilising the hub-angle and hub-velocity feedback signals is used as a feedback controller. Subsequently, to achieve uniform performance in the presence of a payload, a collocated adaptive control is designed based on pole-assignment self-tuning control scheme. Lastly, a comparative assessment of the performance of the hybrid control schemes is presented.
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Verginis, Christos. "Planning and Control of Cooperative Multi-Agent Manipulator-Endowed Systems." Licentiate thesis, KTH, Reglerteknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-223243.
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Multi-agent planning and control is an active and increasingly studied topic of research, with many practical applications, such as rescue missions, security, surveillance, and transportation. More specifically, cases that involve complex manipulator-endowed systems deserve extra attention due to potential complex cooperative manipulation tasks and their interaction with the environment. This thesis addresses the problem of cooperative motion- and task-planning of multi-agent and multi-agent-object systems under complex specifications expressed as temporal logic formulas. We consider manipulator-endowed robotic agents that can coordinate in order to perform, among other tasks, cooperative object manipulation/transportation. Our approach is based on the integration of tools from the following areas: multi-agent systems, cooperative object manipulation, discrete abstraction design of multi-agent-object systems, and formal verification. More specifically, we divide the main problem into three different parts.The first part is devoted to the control design for the formation control of a team of rigid-bodies, motivated by its application to cooperative manipulation schemes. We propose decentralized control protocols such that desired position and orientation-based formation between neighboring agents is achieved. Moreover, inter-agent collisions and connectivity breaks are guaranteed to be avoided. In the second part, we design continuous control laws explicitly for the cooperative manipulation/transportation of an object by a team of robotic agents. Firstly, we propose robust decentralized controllers for the trajectory tracking of the object's center of mass. Secondly, we design model predictive control-based controllers for the transportation of the object with collision and singularity constraints. In the third part, we design discrete representations of multi-agent continuous systems and synthesize hybrid controllers for the satisfaction of complex tasks expressed as temporal logic formulas. We achieve this by combining the results of the previous parts and by proposing appropriate trajectory tracking- and potential field-based continuous control laws for the transitions of the agents among the discrete states. We consider teams of unmanned aerial vehicles and mobile manipulators as well as multi-agent-object systems where the specifications of the objects are also taken into account.Numerical simulations and experimental results verify the claimed results.QC 20180219
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Azad, A. K. M. "Analysis and design of control mechanisms for flexible manipulator systems." Thesis, University of Sheffield, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.312307.
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Chin, Pei-Chieh. "Simulation of manipulator control under combined motor and wrench systems /." The Ohio State University, 1993. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487844948074923.
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Smith, Anthony Lawrence. "Adaptive control of a three link in-parallel manipulator." Thesis, Georgia Institute of Technology, 1990. http://hdl.handle.net/1853/17957.
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Madani, Abdelmalek. "Modelling and control of a two-link flexible manipulator." Thesis, University of Sheffield, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.319485.
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Davidson, Ian Joseph. "Tele-operation of a manipulator using the Internet." Thesis, Georgia Institute of Technology, 1999. http://hdl.handle.net/1853/17623.
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Marr, William J. "Acoustic based tactical control of underwater vehicles." Diss., Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2003. http://library.nps.navy.mil/uhtbin/hyperion-image/03Jun%5FMarr%5FPhD.pdf.
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Thesis (Ph. D. in Mechanical Engineering)--Naval Postgraduate School, June 2003.Dissertation supervisor: Anthony J. Healey. Includes bibliographical references (p. 169-173). Also available online.
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Clegg, Andrew C. "Self-tuning position and force control of a hydraulic manipulator." Thesis, Heriot-Watt University, 2000. http://hdl.handle.net/10399/512.
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勞偉籌 and Wai-chau Edward Lo. "Servo control of robotic manipulator with artificial neural network." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1996. http://hub.hku.hk/bib/B31235128.
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Fraser, Robert James C. "Embedded command and control infrastructures for intelligent autonomous systems." Thesis, University of Southampton, 1994. https://eprints.soton.ac.uk/250158/.
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The issue of Command and Control (C2) is generally associated with the management infrastructure of large scale systems for warfare, public utilities and public transportation, and is concerned with ensuring that the distributed human elements of command and control can be fully integrated into a coherent, total system. Intelligent Autonomous Systems (IASs) are a class of complex systems that perform tasks autonomously in uncertain, dynamic environments, the management of which can be viewed from the perspective of embedded command and control systems. This thesis establishes a vision for the modular construction of intelligent autonomous embedded C2 systems, which defines a complex integration problem characterised by distributed intelligence, world knowledge and control, concurrent processing on heterogeneous platforms, and real-time performance requirements. It concludes that by adopting an appropriate systems infrastructure model, based on Object Technology, it is possible to view the construction of embedded C2 systems as the integration of a temporally assembled collection of reusable components. To support this metaphor it is necessary to construct a common reference model, or standards framework, for the representation and specification of modular C2 systems. This framework must support the coherent long term development and evolution in system capability, ensuring that systems are extensible, robust and perform correctly. In this research, which draws together the themes of other published research in object oriented systems and robotics, classical AI models for intelligent systems architectures are used to specify the overall system structure, with open systems technologies supporting the interoperation of elements within the architecture. All elements of this system are modelled in terms of objects, with well defined, implementation independent interfaces. This approach enables the system to be specified in terms of an object model, and the development process to be framed in terms of object technology, defining a new approach to IAS development. The implementation of an On-board Command and Control System for an Autonomous Underwater Vehicle is used to validate these concepts. The further application of emergent industrial standards in distributed object oriented systems means that this kind of component-based integration is scaleable, providing a near-term solution to generic command and control problems, including Computer Integrated Manufacturing and large scale autonomous systems, where individual autonomous systems, such as robots, form elements of a complete, total intelligent system, for application to areas such as fully automated factories and cooperating intelligent autonomous vehicles for construction sites.
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Maneewarn, Thavida. "Haptic feedback of manipulator kinematic conditioning for teleoperation /." Thesis, Connect to this title online; UW restricted, 2000. http://hdl.handle.net/1773/6107.
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Gueaieb, Wail. "Soft computing based approaches for the robust control of cooperative manipulator systems." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/NQ65242.pdf.
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Chan, Ting. "Analytical methods for power monitoring and control in an underwater observatory /." Thesis, Connect to this title online; UW restricted, 2007. http://hdl.handle.net/1773/6053.
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Yien, Christopher Edward. "Control of a three-link in-parallel manipulator for manufacturing applications." Thesis, Georgia Institute of Technology, 1989. http://hdl.handle.net/1853/17519.
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Glover, James Patrick Neil. "Real time simulation and parallel processing in the control of co-operating manipulator systems." Thesis, Queen's University Belfast, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.359066.
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Swain, Anjan Kumar. "Dynamic modelling and control of robotic manipulators with an investigation of evolutionary computation methods." Thesis, University of Sheffield, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.341801.
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Rokui, Mohammad Reza. "Adaptive control of nonlinear discrete-time systems and its application to control of a flexible-link manipulator." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0003/NQ39786.pdf.
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Smith, Ryan N. "Geometric Control Theory and its Application to Underwater Vehicles." Thesis, University of Hawaii at Manoa, 2008. https://eprints.qut.edu.au/40141/1/40141.pdf.
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This dissertation is based on theoretical study and experiments which extend geometric control theory to practical applications within the field of ocean engineering. We present a method for path planning and control design for underwater vehicles by use of the architecture of differential geometry. In addition to the theoretical design of the trajectory and control strategy, we demonstrate the effectiveness of the method via the implementation onto a test-bed autonomous underwater vehicle.
Bridging the gap between theory and application is the ultimate goal of control theory. Major developments have occurred recently in the field of geometric control which narrow this gap and which promote research linking theory and application. In particular, Riemannian and affine differential geometry have proven to be a very effective approach to the modeling of mechanical systems such as underwater vehicles. In this framework, the application of a kinematic reduction allows us to calculate control strategies for fully and under-actuated vehicles via kinematic decoupled motion planning. However, this method has not yet been extended to account for external forces such as dissipative viscous drag and buoyancy induced potentials acting on a submerged vehicle. To fully bridge the gap between theory and application, this dissertation addresses the extension of this geometric control design method to include such forces.
We incorporate the hydrodynamic drag experienced by the vehicle by modifying the Levi-Civita affine connection and demonstrate a method for the compensation of potential forces experienced during a prescribed motion. We present the design method for multiple different missions and include experimental results which validate both the extension of the theory and the ability to implement control strategies designed through the use of geometric techniques.
By use of the extension presented in this dissertation, the underwater vehicle application successfully demonstrates the applicability of geometric methods to design implementable motion planning solutions for complex mechanical systems having equal or fewer input forces than available degrees of freedom. Thus, we provide another tool with which to further increase the autonomy of underwater vehicles.
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Thome, De Faria Cassio. "Robust Model-Based Control of Nonlinear Systems for Bio-Inspired Autonomous Underwater Vehicles." Diss., Virginia Tech, 2013. http://hdl.handle.net/10919/23792.
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The growing need for ocean surveillance and exploration has pushed the development of novel autonomous underwater vehicle (AUV) technology. A current trend is to make use of bio-inspired propulsor to increase the overall system efficiency and performance, an improvement that has deep implications in the dynamics of the system. The goal of this dissertation is to propose a generic robust control framework specific for bio-inspired autonomous underwater vehicles (BIAUV). These vehicles utilize periodic oscillation of a flexible structural component to generate thrust, a propulsion mechanism that can be tuned to operate under resonance and consequently improve the overall system efficiency. The control parameter should then be selected to keep the system operating in such a condition. Another important aspect is to have a controller design technique that can address the time-varying behaviors, structured uncertainties and system nonlinearities. To address these needs a robust, model-based, nonlinear controller design technique is presented, called digital sliding mode controller (DSMC), which also takes into account the discrete implementation of these laws using microcontrollers. The control law is implemented in the control of a jellyfish-inspired autonomous underwater vehicle.Ph. D.
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Kucuk, Koray. "Modeling And Motion Simulation Of An Underwater Vehicle." Master's thesis, METU, 2007. http://etd.lib.metu.edu.tr/upload/12608918/index.pdf.
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This thesis involves modeling, controller design, and test case simulations for an underwater vehicle. Firstly, a complete dynamic model of the vehicle is developed with six degrees of freedom. The model includes the nonlinearities associated with the hydrodynamic forces and moments. The thrusters of the vehicle are also modeled. Then, using appropriate linearizations of the model, position and rate controllers are designed for the forward, downward, and turning motions of the vehicle. Finally, the designed controllers are tested for various maneuvers by means of simulations using the nonlinear dynamic model of the vehicle. The simulation results show that the designed controllers are quite satisfactory for the intended maneuvers.
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Gibson, Scott Brian. "Improved Dynamic Modeling and Robust Control of Autonomous Underwater Vehicles." Diss., Virginia Tech, 2018. http://hdl.handle.net/10919/84468.
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In this dissertation, we seek to improve the dynamic modeling and control of autonomous underwater vehicles (AUVs). We address nonlinear hydrodynamic modeling, simplifying modeling assumptions, and robust control for AUVs. In the literature, various hydrodynamic models exist with varying model complexity and with no universally accepted model. We compare various hydrodynamic models traditionally employed to predict the motion of AUVs by estimating model coefficients using least-squares and adaptive identifier techniques. Additionally, we derive several dynamic models for an AUV employing varying sets of simplifying assumptions. We experimentally assess the efficacy of invoking typical assumptions to simplify the equations of motion.
For robust control design, we develop a procedure for designing robust attitude controllers based on loop-shaping ideas. We specifically address the challenge of adjusting the desired actuator bandwidth in a loop-shaping design framework. Finally, we present a novel receding horizon H-infinity control algorithm to improve the control of autonomous vehicle systems working in high-disturbance environments, employing a Markov jump linear system framework to model the stochastic and non-stationary disturbances experienced by the vehicle. Our main results include a new Bounded Real Lemma for stability analysis and an output feedback H-infinity control synthesis algorithm.
This work uses numerical simulations and extensive field trials of autonomous underwater vehicles to identify and verify dynamic models and to validate control algorithms developed herein.Ph. D.
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Wang, Jihong. "Practical stabilization of uncertain dynamical systems with application to feedback control of a robotic manipulator." Thesis, Coventry University, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.387521.
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Supriyono, Heru. "Novel bacterial foraging optimisation algorithms with application to modelling and control of flexible manipulator systems." Thesis, University of Sheffield, 2012. http://etheses.whiterose.ac.uk/2122/.
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Biologically-inspired soft-computing algorithms, which were developed by mimicking evolution and foraging techniques of animals in nature, have attracted significant attention of researchers. The works are including the development of the algorithm itself, its modification and its application in broad areas. This thesis presents works on biologically-inspired algorithm based on bacterial foraging algorithm (BFA) and its performance evaluation in modelling and control of dynamic systems. The main aim of the research is to develop new modifications of BFA and its combination with other soft computing techniques and test their performances in modelling and control of dynamic systems. Modification of BFA focuses for improving its convergence in terms of speed and accuracy. The performances of modified BFAs are assessed in comparison to that of original BFA. In the original BFA, in this thesis referred as standard BFA (SBFA), bacteria use constant chemotactic step size to head to global optimum location. Very small chemotactic step size around global optimum location will assure bacteria find the global optimum point. However, a large number of steps is needed for the whole optimisation process. Moreover, there is potential for the algorithm to be trapped in one of the local optima. On the contrary, big chemotactic step size will assure bacteria have faster convergence speed but the literature shows that it results oscillation around global optimum point and the algorithm potentially missing the global optimum point and leading to oscillation around the point. Thus SBFA can be improved by applying adaptable chemotactic step size which could change: very large when bacteria are in locations far away from the global optimum location, to speed up the convergence, and very small when bacteria are in the locations near the global optimum so that bacteria able to find global optimum point without oscillation. Here, four novel adaptation schemes allowing the chemotactic step size to depending on the cost function value have been proposed. The adaptation schemes are developed based on linear, quadratic and exponential functions as well as fuzzy logic (FL). Then, the proposed BFAs with adaptable chemotactic step size, i.e. linearly adaptable BFA (LABFA), quadratic adaptable BFA (QABFA), exponentially adaptable BFA (EABFA) and fuzzy adaptable chemotactic step size (FABFA), are validated by using them to find global minimum point of seven well-known benchmark functions commonly used in development of optimisation techniques development. The results show that all ABFAs achieve better accuracy and speed compared to those of SBFA. The ABFAs are then used in modelling and control of a single-link flexible manipulator system. This includes modelling (based on linear model structures, neural network (NN), and fuzzy logic (FL)), optimising joint-based collocated (JBC) proportional-derivative (PD) control, and optimising both PD and proportional integral derivative (PID) control of end-point acceleration feedback for vibration reduction of a single-link flexible manipulator. The results show that ABFAs outperform SBFA in terms of convergence speed and accuracy. Since all SBFA and ABFAs use the same general parameters and bacteria are initially placed randomly across the nutrient media (cost function), the superiority better performance of ABFAs are attributed to the proposed adaptable chemotactic step size.
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Pauck, Simon James. "Movement control and guidance of an automated underwater vehicle." Thesis, Stellenbosch : University of Stellenbosch, 2010. http://hdl.handle.net/10019.1/4244.
Full textAbstract:
Thesis (MScEng (Electrical and Electronic Engineering))--University of Stellenbosch, 2010.ENGLISH ABSTRACT: This thesis presents the design process of the movement control and guidance systems for an automated underwater vehicle (AUV) constructed by the Institute of Maritime Technology in Simon’s Town. The full non-linear mathematical model and simulation environment for the AUV were previously developed in [1]. The design process in this thesis covers an analysis of existing test data and the performance of the current systems in place on the AUV, derivation and analysis of the linear model for the AUV, design of upgraded control and guidance systems, analysis of the new designs including simulation results, practical implementation of the new designs and the results thereof. Over the course of this project a number of flaws were identified in the original control designs and other aspects of the AUV. Most notably, the capability of the AUV is limited owing to its construction, and the current control and guidance methods result in poor movement characteristics. The new control designs are executed through multiple SISO feedback loops, with the most complicated controllers consisting of proportional and integral control. A completely new guidance method was designed which grants theAUVthe ability to track both straight line and circular path segments with no steady state error. These designs were tested in simulation, with results showing good tracking performance, even in the presence of output disturbances. The new designs were implemented on the physical AUV, but testing was limited, with poor results being obtained. The poor test results were caused primarily by the construction of the AUV.
AFRIKAANSE OPSOMMING: Hierdie tesis stel die ontwerpsproses voor vir die bewegingsbeheer- en navigasiestelsels vir ’n outonome duikboot wat gebou is deur die Instituut vir Maritieme Tegnologie in Simonstad. Die volle nie-lineˆere wiskundige model en simulasieomgewing vir die duikboot is voorheen ontwikkel in [1]. Die ontwerpsproses in hierdie tesis behels ’n analise van bestaande toetsdata en van die werksverrigting van die stelsels wat tans op die duikboot ge¨ınstalleer is, die afleiding en analise van ’n lineˆere model vir die duikboot, die ontwerp van verbeterde beheer- en navigasiestelsels, die analise van die nuwe ontwerpe, wat simulasieresultate insluit, die praktiese implementering van die nuwe ontwerpe, en die resultate daarvan. Deur die loop van die projek is ’n aantal tekortkominge ge¨ıdentifiseer in die oorspronklike beheerstelselontwerpe en ander aspekte van die duikboot. Die mees beduidende tekortkominge is dat die vermo¨e van die duikboot beperk word deur die konstruksie daarvan, en dat die huidige beheer- en navigasietegnieke swak bewegingseienskappe lewer. Die nuwe beheerstelselontwerpe is uitgevoer deur ’n aantal enkelintree, enkeluittree terugvoerlusse, waar die mees komplekse beheerders bestaan uit proporsionele en integraalbeheer. ’n Heeltemal nuwe navigasiemetode is ontwerp, wat die duikboot in staat stel om beide reguit lyne en sirkulˆere padsegmente te volg sonder ’n stasionˆere volgfout. Hierdie ontwerpe is getoets in simulasie, waar die resultate goeie volging getoon het, selfs in die teenwoordigheid van uittreeversteurings. Die nuwe ontwerpe is ge¨ımplementeer op die fisiese duikboot, maar beperkte toetse is gedoen, en het swak resultate gelewer. Die swak toetsresultate was hoofsaaklik as gevolg van die konstruksie van die duikboot.
33
Watson, Simon Andrew. "Mobile platforms for underwater sensor networks." Thesis, University of Manchester, 2012. https://www.research.manchester.ac.uk/portal/en/theses/mobile-platforms-for-underwater-sensor-networks(00f93130-f9d6-4479-80ab-58a0c60327c0).html.
Full textAbstract:
The production of clean water, the generation of nuclear power and the development of chemicals, petro-chemicals and pharmaceuticals all rely on liquid-based processes. They are fundamental to modern society, however the real-time monitoring of such processes is an inherently difficult challenge which has not yet been satisfactorily solved.Current methods of monitoring include on- and off-line spot checks and industrial process tomography. Neither of these methods provides the spatial or temporal resolution required to properly characterise the processes. This research project proposes a new monitoring method for processes which can tolerate foreign objects; a mobile underwater sensor network (MUSN).An MUSN has the potential to increase both the spatial and temporal resolution of measurements and could be used in real-time. The network would be formed by a number of mobile sensor platforms, in the form of micro-autonomous underwater vehicles (uAUVs) which would communicate using acoustics. The demonstrator for the technology is for use in the monitoring of nuclear storage ponds.Current AUV technology is not suitable for use in enclosed environments such as storage ponds due to the size and maneuverability. This thesis presents the research conducted in the development of a new vehicle uAUV. The work presented covers the mechatronic aspects of the vehicle; the design of the hull, propulsion systems, corresponding control circuitry and basic motion control systems. One of the main factors influencing the design of the vehicle has been cost. If a large number of vehicles are used to form a network, the cost of an individual uAUV should be kept as low as possible. This has raised a number of technical challenges as low-cost components are often of low-tolerance. Imbalanced time-varying thrust, low manufacturing tolerances and noisy indirect sensor measurements for the control systems have all been overcome in the design of the vehicle. The outcome of the research is a fully functional prototype uAUV. The vehicle is spherical in shape with a diameter of approximately 15cm, with six thruster units mounted around the equator (increasing the horizontal clearance to 20cm) to provide thrust in four degrees of freedom (surge, sway, heave and yaw). The vehicle has a sensor suite which includes a pressure sensor, digital compass and a gyroscope which provide inputs to the motion control systems. The controllers have been developed and implemented on the vehicle's custom built embedded system. Experiments have been conducted showing that the uAUV is able to move in 3D with closed-loop control in heave and yaw. Motion in surge and sway is open-loop, via a dead-reckoning system.
34
Maalouf, Divine. "Contribution to nonlinear adaptive control of low inertia underwater robots." Thesis, Montpellier 2, 2013. http://www.theses.fr/2013MON20196/document.
Full textAbstract:
L'utilisation des véhicules sous-marins (ROV, AUV, gliders) s'est considérablement accrue ces dernières décennies, aussi bien dans le domaine de l'offshore ou de l'océanographie, que pour des applications militaires. Dans cette thèse, nous abordons le problème particulier de la commande des véhicules sous-marins à faible inertie et fort rapport puissance/inertie. Ces derniers constituent des systèmes fortement non linéaires, dont la dynamique est susceptible de varier au cours du temps (charge embarquée, caractéristiques des propulseurs, variation de salinité...) et qui sont très sensibles aux perturbations environnementales (chocs, traction sur l'ombilical...). Afin d'assurer des performances de suivi de trajectoire satisfaisantes, il est nécessaire d'avoir recours à une commande adaptative qui compense les incertitudes ou les variations des paramètres du modèle dynamique, mais également qui rejette les perturbations, telles que les chocs. A cette fin, nous proposons dans ce manuscrit, l'étude théorique et la validation expérimentale de plusieurs lois de commande pour véhicules sous-marins. Nous analysons tout d'abord des approches classiques dans ce domaine (commande PID et commande par retour d'état non linéaire), puis nous les comparons avec deux autres architectures de commande. La première est la commande adaptative L1 non linéaire, introduite en 2010 notamment pour la commande des véhicules aériens, et implémentée pour la première fois sur un véhicule sous-marin. Le découplage entre adaptation et robustesse permet l'utilisation de très grands gains d'adaptation (et donc une convergence plus rapide des paramètres estimés, sans aucune connaissance a priori), sans pour autant dégrader la stabilité. La seconde méthode, que nous proposons et qui constitue l'apport principal de cette thèse, est une évolution de la commande L1, permettant d'en améliorer les performances lors du suivi d'une trajectoire variable. Nous présentons une analyse de stabilité de cette commande, ainsi que sa comparaison expérimentale avec les autres lois de commande (commande PID, commande adaptative par retour d'état non linéaire et commande adaptative L1 standard). Ces expérimentations ont été réalisées sur un mini-ROV et plusieurs scenarii ont été étudiés, permettant ainsi d'évaluer, pour chaque loi, sa robustesse et son aptitude à rejeter les perturbationsUnderwater vehicles have gained an increased interest in the last decades given the multiple tasks they can accomplish in various fields, ranging from scientific to industrial and military applications. In this thesis, we are particularly interested in the category of vehicles having a high power to weight ratio. Different challenges in autonomous control of such highly unstable systems arise from the inherent nonlinearities and the time varyingbehavior of their dynamics. These challenges can be increased by the low inertia of this class of vehicles combined with their powerful actuation. A self tuning controller is therefore required in order to avoid any performance degradation during a specific mission. The closed-loop system is expected to compensate for different kinds of disturbances or changes in the model parameters. To solve this problem, we propose in this work the design,analysis and experimental validation of different control schemes on an underwater vehicle. Classical methods are initially proposed, namely the PID controller and the nonlinear adaptive state feedback (NASF) one, followed by two more advanced schemes based on the recently developed L1 adaptive controller. This last method stands out among the other developed ones in its particular architecture where robustness and adaptation are decoupled. In this thesis, the original L1 adaptive controller has been designed and successfullyvalidated then an extended version of it is proposed in order to deal with the observed time lags occurring in presence of a varying reference trajectory. The stability of this latter controller is then analysed and real-time experimental results for different operating conditions are presented and discussed for each proposed controller, assessing their performance and robustness
35
Bhattacharyya, Siddhartha. "HIERARCHICAL HYBRID-MODEL BASED DESIGN, VERIFICATION, SIMULATION, AND SYNTHESIS OF MISSION CONTROL FOR AUTONOMOUS UNDERWATER VEHICLES." UKnowledge, 2005. http://uknowledge.uky.edu/gradschool_diss/344.
Full textAbstract:
The objective of modeling, verification, and synthesis of hierarchical hybrid mission control for underwater vehicle is to (i) propose a hierarchical architecture for mission control for an autonomous system, (ii) develop extended hybrid state machine models for the mission control, (iii) use these models to verify for logical correctness, (iv) check the feasibility of a simulation software to model the mission executed by an autonomous underwater vehicle (AUV) (v) perform synthesis of high-level mission coordinators for coordinating lower-level mission controllers in accordance with the given mission, and (vi) suggest further design changes for improvement. The dissertation describes a hierarchical architecture in which mission level controllers based on hybrid systems theory have been, and are being developed using a hybrid systems design tool that allows graphical design, iterative redesign, and code generation for rapid deployment onto the target platform. The goal is to support current and future autonomous underwater vehicle (AUV) programs to meet evolving requirements and capabilities. While the tool facilitates rapid redesign and deployment, it is crucial to include safety and performance verification into each step of the (re)design process. To this end, the modeling of the hierarchical hybrid mission controller is formalized to facilitate the use of available tools and newly developed methods for formal verification of safety and performance specifications. A hierarchical hybrid architecture for mission control of autonomous systems with application to AUVs is proposed and a theoretical framework for the models that make up the architecture is outlined. An underwater vehicle like any other autonomous system is a hybrid system, as the dynamics of the vehicle as well as its vehicle level control is continuous whereas the mission level control is discrete, making the overall system a hybrid system i.e., one possessing both continuous and discrete states. The hybrid state machine models of the mission controller modules is derived from their implementation done using TEJA, a software for representing hybrid systems with support for auto code generation. The verification of their logical correctness properties has been done using UPPAAL, a software tool for verification of timed automata a special kind of hybrid system. A Teja to Uppaal converter, called dem2xml, has been created at Applied Reserarch Lab that converts a hybrid (timed) autonomous system description in Teja to an Uppaal system description. Verification work involved developing abstract models for the lower level vehicle controllers with which the mission controller modules interact and follow a hierarchical approach: Assuming the correctness of level-zero or vehicle controllers, we establish the correctness of level-one mission controller modules, and then the correctness of level-two modules, etc. The goal of verification is to show that any valid meaning for a mission formalized in our research verifies the safe and correct execution of actions. Simulation of the sequence of actions executed for each of the operations give a better view of the combined working of the mission coordinators and the low level controllers. So we next looked into the feasibility of simulating the operations executed during a mission. A Perl program has been developed to convert the UPPAAL files in .xml format to OpenGL graphic files. The graphic files simulate the steps involved in the execution of a sequence of operations executed by an AUV. The highest level coordinators send mission orders to be executed by the lower level controllers. So a more generalized design of the highest level controllers would help to incorporate the execution of a variety of missions for a vast field of applications. Initially, we consider manually synthesized mission coordinator modules. Later we design automated synthesis of coordinators. This method synthesizes mission coordinators which coordinate the lower level controllers for the execution of the missions ordered and can be used for any autonomous system.
36
Lozano, Martin Jr. "Design and control of a spheroidal underwater robot for the inspection of nuclear piping systems." Thesis, Massachusetts Institute of Technology, 2012. http://hdl.handle.net/1721.1/74449.
Full textAbstract:
Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2012.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 59-60).
While it is critical that nuclear plants frequently inspect their facilities for cracking, corrosion or other failure modes, humans cannot safely perform these tasks due to the hazardous conditions within the tanks and piping systems. In response, the d'Arbeloff Laboratory in the Mechanical Engineering department is designing a compact submersible robot that is capable of precise navigation and maneuvering in order to detect defects within water filled piping systems. The robot is spheroidal with a smooth surface and no external appendages. It propels itself with centrifugal pumps which suck in water from the environment, and pump it out in various directions. This thesis covers the design and implementation of the software, electrical, and a few mechanical systems of the robot. Specifically, it details the programming techniques for the microcontroller and graphical user interface code, circuit board design, wiring, and waterproofing. A robot prototype was built, and experiments have given useful data to construct a model to supplement the field of underwater robotic design.
by Martin Lozano, Jr..
S.B.
37
Ellery, Alexander. "Systems design and control of a freeflying space robotic manipulator system (ATLAS) for in-orbit satellite servicing operations." Thesis, Cranfield University, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.359995.
Full text
38
Roberson, David Gray. "Environmental Tracking and Formation Control for an Autonomous Underwater Vehicle Platoon with Limited Communication." Diss., Virginia Tech, 2008. http://hdl.handle.net/10919/26175.
Full textAbstract:
A platoon of autonomous underwater vehicles provides a compelling platform for studying many challenging issues in multi-agent cooperative control. These challenges include developing cooperative algorithms suitable to practical multi-vehicle applications. They also include addressing intervehicle communication issues, such as sharing information via limited bandwidth channels and selecting network architecture to facilitate control design. This work addresses problems in each of these areas.
Environmental tracking and formation control serves as the main application upon which this work focuses. In the tracking and formation control application, a team of vehicles obtains a spatial average of an environmental feature by collecting and sharing local measurements. To achieve this objective, vehicles track a desired environmental field contour with their average position while maintaining a desired spatial formation about the average. A decentralized consensus-based algorithm is developed for controlling the platoon. In a novel two-level consensus approach, each vehicle estimates a virtual leader trajectory using local and shared measurements at one level, then positions itself about the virtual leader at a second level.
Due to very low bandwidth underwater communication, vehicles share information intermittently, and the platoon network is effectively disconnected at every instant of time. This issue is addressed by modeling the platoon as a periodic switched system whose frozen-time subsystems possess disconnected networks, but whose time-averaged system is connected. The stability and input-output properties of the switched system are related to those of the corresponding average system. Under sufficiently fast switching, asymptotic stability of the average system implies asymptotic stability of the switched system and the existence of an L2 gain. Estimates of the slowest stabilizing switching rate and the L2 gain are derived.
Controller and estimator design are complicated by the lack of a separation principle for decentralized systems and by the effects of intervehicle coupling. The potential for choosing the communication topology in a manner that leads to design simplifications is investigated. In particular, a transformation is presented that converts the platoon state coefficient matrix to block diagonal form when the communication network has a circulant structure.Ph. D.
39
Davis, Duane T. "Precision control and maneuvering of the Phoenix autonomous underwater vehicle for entering a recovery tube." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1996. http://handle.dtic.mil/100.2/ADA325015.
Full textAbstract:
Thesis (M.S. in Computer Science) Naval Postgraduate School, September 1996.Thesis advisor(s): Robert McGhee and Don Brutzman. "September 1996." Appendix videotape located at Circulation Desk, call number VHS 5000067. Includes bibliographical references (p. 179-184). Also available online.
40
NIGRI, ILANA. "COMPARISON BETWEEN LOOK-AND-MOVE AND VISUAL SERVO CONTROL USING SIFT TRANSFORMS IN EYE-IN-HAND MANIPULATOR SYSTEMS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2009. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=15390@1.
Full textAbstract:
CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOVisão Computacional pode ser utilizada para calibrar e auto-localizar robôs. Existem diversas aplicações de auto-localização e controle aplicadas a manipuladores industriais e robôs móveis. Em particular, o controle visual pode ser útil em intervenções submarinas, nas quais um manipulador robótico é acoplado a um ROV (Veículo de Operação Remota) para execução de tarefas em grandes profundidades, como o manuseio de válvulas de equipamentos como manifolds. Este trabalho tem como objetivo desenvolver e implementar técnicas de controle visual para auto-localização e posicionamento de manipuladores robóticos. Assume-se que o manipulador possui uma câmera presa em sua extremidade (configuração eye-in-hand). Duas técnicas de controle visual são estudadas: look-and-move e servo-visual, que diferem entre si pela realimentação do controle. A primeira utiliza sensores de posição, a partir de uma única imagem capturada no início da movimentação. A segunda utiliza diversas imagens capturadas durante o processo. A principal contribuição deste trabalho está no uso da transformada SIFT, robusta a rotações, translações, mudança de escala e iluminação, para obter e correlacionar pontos-chave entre as imagens de referência e capturadas em tempo real. A metodologia é validada experimentalmente através de um manipulador robótico baseado na estrutura mecânica de uma mesa x-y-0. Um sistema eletrônico é utilizado como interface entre o robô e o software de controle, onde estão implementadas todas as técnicas propostas. Testes iniciais são realizados com imagens de objetos circulares, sem o uso de transformações como o SIFT. Em seguida, são feitos testes com a imagem de um painel real de um manifold, utilizando transformadas SIFT para determinar a localização do manipulador em relação ao painel e controlá-lo até uma pose desejada. Os resultados mostram que o desempenho do controle servo-visual depende muito do tempo de processamento de cada imagem, ao contrário do look-and-move. No entanto, o controle servo-visual apresenta erros finais de posicionamento muito menores. O método SIFT é apropriado para uso em ambos os controles, desde que a resolução das imagens seja alta o suficiente para evitar correlações falsas.
Computer vision can be used to calibrate and self-localize robots. There are many applications in self-localization and control applied to industrial manipulators and mobile robots. In particular, visual control can be useful in submarine interventions, where a robotic manipulator is mounted on a Remote Operated Vehicle (ROV) to execute tasks at high depths, such as handling manifold valves. This work has the objective to develop and implement visual control techniques to self-localize and position robotic manipulators. It is assumed that a monocular camera is attached to the robot end-effector (eye-in-hand configuration). Two visual control techniques are studied: look-and-move and visual servo control. Their main difference is related to the adopted feedback sensors. The first technique uses position sensors with the aid of a single image captured at the beginning of the robot movement. The second technique relies on several images captured in real time during the robot movement. The main contribution of this work is the use of the SIFT transform, robust to rotation, translation, changes in scale and illumination, to obtain and correlate key-points between reference images and images captured in real time. The methodology is experimentally validated using a manipulator based on the mechanical structure of an x-y-0 coordinate table. An electronic system was developed to control the robot through a software in a computer, where were implemented all the techniques proposed. Preliminary tests are performed on simple circular-shaped objects, without the need for SIFT transforms. Next, tests are performed with a photo of an actual manifold panel typically used in submarine interventions, using SIFT transform to find the localization of the manipulator with respect to the panel. The results show that the performance of the visual servo control depends on the image processing time, unlike the look-and-move. However, the visual-servo control presents smaller positioning errors. The SIFT method is appropriate for both controls, since image resolution be high enough to avoid false matching.
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Bilale, Abudureheman. "State relativity and speed-allocated line-of-sight course control for path-following of underwater vehicles." Thesis, Cranfield University, 2018. http://dspace.lib.cranfield.ac.uk/handle/1826/13963.
Full textAbstract:
Path-following is a primary task for most marine, air or space crafts, especially during autonomous operations. Research on autonomous underwater vehicles (AUV) has received large interests in the last few decades with research incentives emerging from the safe, cost-effective and practical solutions provided by their applications such as search and rescue, inspection and monitoring of pipe-lines ans sub-sea structures. This thesis presents a novel guidance system based on the popular line-of-sight (LOS) guidance law for path-following (PF) of underwater vehicles (UVs) subject to environmental disturbances. Mathematical modeling and dynamics of (UVs) is presented first. This is followed by a comprehensive literature review on guidance-based path-following control of marine vehicles, which includes revised definitions of the track-errors and more detailed illustrations of the general PF problem. A number of advances on relative equations of motion are made, which include an improved understanding of the fluid FLOW frame and expression of its motion states, an analytic method of modeling the signs of forces and moments and the proofs of passivity and boundedness of relative UV systems in 3-D. The revision in the relative equations of motion include the concept of state relativity, which is an improved understanding of relativity of motion states expressed in reference frames and is also useful in incorporating environmental disturbances. In addition, the concept of drift rate is introduced along with a revision on the angles of motion in 3-D. A switching mechanism was developed to overcome a drawback of a LOS guidance law, and the linear and nonlinear stability results of the LOS guidance laws have been provided, where distinctions are made between straight and curved PF cases. The guidance system employs the unique formulation and solution of the speed allocation problem of allocating a desired speed vector into x and y components, and the course control that employs the slip angle for desired heading for disturbance rejection. The guidance system and particularly the general course control problem has been extended to 3-D with the new definition of vertical-slip angle. The overall guidance system employing the revised relative system model, course control and speed allocation has performed well during path-following under strong ocean current and/or wave disturbances and measurement noises in both 2-D and 3-D scenarios. In 2-D and 3-D 4 degrees-of-freedom models (DOF), the common sway-underactuated and fully actuated cases are considered, and in 3-D 5-DOF model, sway and heave underactuated and fully actuated cases are considered. Stability results of the LOS guidance laws include the semi-global exponential stability (SGES) of the switching LOS guidance and enclosure-based LOS guidance for straight and curved paths, and SGES of the loolahead-based LOS guidance laws for curved paths. Feedback sliding mode and PID controllers are applied during PF providing a comparison between them, and simulations are carried out in MatLab.
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Yang, Hee Doo. "Design, Manufacturing, and Control of Soft and Soft/Rigid Hybrid Pneumatic Robotic Systems." Diss., Virginia Tech, 2019. http://hdl.handle.net/10919/100635.
Full textAbstract:
Soft robotic systems have recently been considered as a new approach that is in principle better suited for tasks where safety and adaptability are important. That is because soft materials are inherently compliant and resilient in the event of collisions. They are also lightweight and can be low-cost; in general, soft robots have the potential to achieve many tasks that were not previously possible with traditional robotic systems.
In this paper, we propose a new manufacturing process for creating multi-chambered pneumatic actuators and robots. We focus on using fabric as the primary structural material, but plastic films can be used instead of textiles as well. We introduce two different methods to create layered bellows actuators, which can be made with a heat press machine or in an oven. We also describe origami-like actuators with possible corner structures. Moreover, the fabrication process permits the creation of soft and soft/rigid hybrid robotic systems, and enables the easy integration of sensors into these robots. We analyze various textiles that are possibly used with this method, and model bellows actuators including operating force, restoring force, and estimated geometry with multiple bellows. We then demonstrate the process by showing a bellows actuator with an embedded sensor and other fabricated structures and robots.
We next present a new design of a multi-DOF soft/rigid hybrid robotic manipulator. It contains a revolute actuator and several roll-pitch actuators which are arranged in series. To control the manipulator, we use a new variant of the piece-wise constant curvature (PCC) model. The robot can be controlled using forward and inverse kinematics with embedded inertial measurement units (IMUs). A bellows actuator, which is a subcomponent of the manipulator, is modeled with a variable-stiffness spring, and we use the model to predict the behavior of the actuator. With the model, the roll-pitch actuator stiffnesses are measured in all directions through applying forces and torques. The stiffness is used to predict the behavior of the end effector. The robotic system introduced achieved errors of less than 5% when compared to the models, and positioning accuracies of better than 1cm.Doctor of Philosophy
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Gul, Ugur Dogan. "Navigation And Path Planning Of An Unmanned Underwater Vehicle." Master's thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12614706/index.pdf.
Full textAbstract:
Due to the conditions peculiar to underwater, distinctive approaches are required to solve the navigation and path planning problem of an unmanned underwater vehicle (UUV). In this study, first of all, a detailed 6 degrees-of-freedom (DOF) mathematical model is formed, including the coupled non-linear forces and moments acting on an underwater vehicle. The hydrodynamic coefficients which correspond to the geometry of the vehicle which the model is based on are calculated using the strip theory. After the mathematical model is obtained, by applying appropriate linearization on the model, &ldquoLinear Quadratic Regulator (LQR)&rdquo
control method is implemented to govern the surge, heave, pitch and yaw motions of the underwater vehicle. Path planning algorithm of the vehicle is based on tracking the waypoints. Permutation of the waypoints is obtained by solving the &ldquo
Travelling Salesman Problem (TSP)&rdquo
via genetic algorithm. Linked with that, &ldquo
Rapidly-Exploring Random Trees (RRT)&rdquo
algorithm is introduced into the path planning algorithm to avoid collisions in environments with obstacles. Underwater navigation solution is based on the &ldquo
Inertial Navigation System (INS)&rdquo
outputs, located on the vehicle. To correct the long-term drift of the inertial solution, &ldquo
Kalman Filter&rdquo
based integration algorithm is used and external aids such as &ldquo
Global Navigation Satellite System (GNSS)&rdquo
, &ldquo
Ultra-Short Baseline (USBL)&rdquo
acoustic navigation system and attitude sensors have been utilized. The control method, path planning and navigation algorithms used in this study are verified by simulation results.
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Geridonmez, Fatih. "Simulation Of Motion Of An Underwater Vehicle." Master's thesis, METU, 2007. http://etd.lib.metu.edu.tr/upload/12608765/index.pdf.
Full textAbstract:
In this thesis, a simulation package for the Six Degrees of Freedom (6DOF) motion
of an underwater vehicle is developed. Mathematical modeling of an underwater
vehicle is done and the parameters needed to write such a simulation package are
obtained from an existing underwater vehicle available in the literature.
Basic equations of motion are developed to simulate the motion of the underwater
vehicle and the parameters needed for the hydrodynamic modeling of the vehicle is
obtained from the available literature.
6DOF simulation package prepared for the underwater vehicle was developed using
the MATLAB environment. S-function hierarchy is developed using the same
platform with C++ programming language. With the usage of S-functions the
problems related to the speed of the platform have been eliminated. The use of Sfunction
hierarchy brought out the opportunity of running the simulation package
on other independent platforms and get results for the simulation.
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Solowjow, Eugen [Verfasser], and Edwin [Akademischer Betreuer] Kreuzer. "Design, dynamics, and control of micro underwater vehicle systems for autonomous environmental exploration / Eugen Solowjow ; Betreuer: Edwin Kreuzer." Hamburg : Universitätsbibliothek der Technischen Universität Hamburg-Harburg, 2019. http://d-nb.info/1175660779/34.
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Bhat, Sriharsha. "Hydrobatics: Efficient and Agile Underwater Robots." Licentiate thesis, KTH, Farkostteknik och Solidmekanik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-286062.
Full textAbstract:
The term hydrobatics refers to the agile maneuvering of underwater vehicles. Hydrobatic capabilities in autonomous underwater vehicles (AUVs) can enable increased maneuverability without a sacrifice in efficiency and speed. This means innovative robot designs and new use case scenarios are possible. Benefits and technical challenges related to hydrobatic AUVs are explored in this thesis. The dissertation contributes to new knowledge in simulation, control and field applications, and provides a structured approach to realize hydrobatic capabilities in real world impact areas. Three impact areas are considered - environmental monitoring, ocean production and security. A combination of agility in maneuvering and efficiency in performance is crucial for successful AUV applications. To achieve such performance, two technical challenges must be solved. First, these AUVs have fewer control inputs than degrees of freedom, which leads to the challenge of underactuation. The challenge is described in detail and solution strategies that use optimal control and model predictive control (MPC) are highlighted. Second, the flow around an AUV during hydrobatic maneuvers transitions from laminar to turbulent flow at high angles of attack. This renders flight dynamics modelling difficult. A full 0-360 degree envelope flight dynamics model is therefore derived, which combines a multi-fidelity hydrodynamic database with a generalized component-buildup approach. Such a model enables real-time (or near real-time) simulations of hydrobatic maneuvers including loops, helices and tight turns. Next, a cyber-physical system (CPS) is presented -- it safely transforms capabilities derived in simulation to real-world use cases in the impact areas described. The simulator environment is closely integrated with the robotic system, enabling pre-validation of controllers and software before hardware deployment. The small and hydrobatic SAM AUV (developed in-house at KTH as part of the Swedish Maritime Robotics Center) is used as a test platform. The CPS concept is validated by using the SAM AUV for the search and detection of a submerged target in field operating conditions. Current research focuses on further exploring underactuated control and motion planning. This includes development of real-time nonlinear MPC implementations running on AUV hardware, as well as intelligent control through feedback motion planning, system identification and reinforcement learning. Such strategies can enable real-time robust and adaptive control of underactuated systems. These ideas will be applied to demonstrate new capabilities in the three impact areas.Termen hydrobatik avser förmåga att utföra avancerade manövrer med undervattensfarkoster. Syftet är att, med bibehållen fart och räckvidd, utvigda den operationella förmågan i manövrering, vilket möjliggör helt nya användningsområden för maximering av kostnadseffektivitet. I denna avhandling undersöks fördelar och tekniska utmaningar relaterade till hydrobatik som tillämpas på undervattensrobotar, vanligen kallade autonoma undervattensfarkoster (AUV). Avhandlingen bidrar till ny kunskap i simulering, reglering samt tillämpning i experiment av dessa robotar genom en strukturerad metod för att realisera hydrobatisk förmåga i realistiska scenarier. Tre nyttoområden beaktas - miljöövervakning, havsproduktion och säkerhet. Inom dessa nyttoområden har ett antal scenarios identifierats där en kombination av smidighet i manövrerbarhet samt effektivitet i prestanda är avgörande för robotens förmåga att utföra sin uppgift. För att åstadkomma detta måste två viktiga tekniska utmaningar lösas. För det första har dessa AUVer färre styrytor/trustrar än frihetsgrader, vilket leder till utmaningen med underaktuering. Utmaningen beskrivs i detalj och lösningsstrategier som använder optimal kontroll och modellprediktiv kontroll belyses. För det andra är flödet runt en AUV som genomför hydrobatiska manövrar komplext med övergång från laminär till stark turbulent flöde vid höga anfallsvinklar. Detta gör flygdynamikmodellering svår. En full 0-360 graders flygdynamikmodell härleds därför, vilken kombinerar en multi-tillförlitlighets hydrodynamisk databas med en generaliserad strategi för komponentvis-superpositionering av laster. Detta möjliggör prediktering av hydrobatiska manövrar som t.ex. utförande av looping, roll, spiraler och väldigt snäva svängradier i realtids- eller nära realtids-simuleringar. I nästa steg presenteras ett cyber-fysikaliskt system (CPS) – där funktionalitet som härrör från simuleringar kan överföras till de verkliga användningsområdena på ett effektivt och säkert sätt. Simulatormiljön är nära integrerad i robot-miljön, vilket möjliggör förvalidering av reglerstrategier och mjukvara innan hårdvaruimplementering. En egenutvecklad hydrobatisk AUV (SAM) används som testplattform. CPS-konceptet valideras med hjälp av SAM i ett realistiskt sceanrio genom att utföra ett sökuppdrag av ett nedsänkt föremål under fältförhållanden. Resultaten av arbetet i denna licentiatavhandling kommer att användas i den fortsatta forskningen som fokuserar på att ytterligare undersöka och utveckla ny metodik för reglering av underaktuerade AUVer. Detta inkluderar utveckling av realtidskapabla ickelinjära MPC-implementeringar som körs ombord, samt AI-baserade reglerstrategier genom ruttplaneringsåterkoppling, autonom systemidentifiering och förstärkningsinlärning. Sådan utveckling kommer att tillämpas för att visa nya möjligheter inom de tre nyttoområdena.
SMaRC
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KHALAF, POYA. "Design, Control, and Optimization of Robots with Advanced Energy Regenerative Drive Systems." Cleveland State University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=csu1552923998768344.
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Dang, Anh X. H. "Theoretical and experimental development of an active acceleration compensation platform manipulator for transport of delicate objects." Diss., Georgia Institute of Technology, 2002. http://hdl.handle.net/1853/17277.
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Teoh, Pek Loo. "A study of single laser interferometry-based sensing and measuring technique in robot manipulator control and guidance. Volume 1." Monash University, Dept. of Mechanical Engineering, 2003. http://arrow.monash.edu.au/hdl/1959.1/9565.
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Ogan, Osman Can. "Modeling And Control Of Constrained Flexible Joint Parallel Manipulators." Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/12611548/index.pdf.
Full textAbstract:
The purpose of the thesis is to achieve a hybrid force and motion control
method of parallel manipulators working in a constrained environment, in the
presence of joint flexibility that occurs at the actuated joints.
A flexible joint is modeled and the equations of motion of the parallel
manipulator are derived by using the Lagrange formulation. The structural
damping of the active joints, viscous friction at the passive joints and the rotor
damping are also considered in the model. It is shown that in a flexible joint
manipulator, the acceleration level inverse dynamic equations are singular
because the control torques do not have instantaneous effect on the manipulator
end-effector contact forces and accelerations due to the flexibility. Implicit
numerical integration methods are utilized for solving the singular equations.
As a case study, a two legged constrained planar parallel manipulator with
three degrees of freedom is simulated to illustrate the performance of the
method.