O presente trabalho descreve o desenvolvimento de um projeto para auxílio no ensino de robôs manipuladores em nível superior utilizando uma plataforma PC com sistema de segurança e software de tempo real. O sistema permite aos alunos testar soluções já existentes e configurar suas próprias alternativas para simulação e controle de um robô manipulador real com até seis graus de liberdade. / This text describes the project development to aid the robot manipulator learning at undergraduate courses using a PC-based architecture with security system and real time software. The system allows the students to test previous solutions and configure their own alternatives for simulating and controlling a real robot manipulator with up to six degrees-of-freedom

Este trabalho trata do controle Markoviano aplicado a um robô manipulador visando obter um sistema tolerante a falhas. Os controladores H2, H&#8734, e H2/H&#8734 Markovianos são calculados e aplicados ao robô em diversas situações de operação. Os controladores obtidos mantiveram a estabilidade do sistema tanto em situações de operação normal, quanto em situações de falhas sucessivas. / This work deals with Markovian control applied to a robot manipulator, in an effort to obtain a fault tolerant system. The H2, H&#8734, and H2/H&#8734 controllers were calculated and applied to the robot in different operation situations. The obtained controllers guaranteed the stability of the system in both situations: normal operation, and successive faults operation.

Este trabalho contempla o projeto de um manipulador robótico cilindro atuado por motores de passo com cinco juntas de atuação. As etapas do projeto do robô, que tratam este estudo, foram divididas em: projeto mecânico; modelagem matemática; projeto do controlador; e simulações. O projeto mecânico apresenta uma proposta de configuração e dimensionamento mecânicos que supre a demanda exigida para a operação analisada. O modelo matemático apresenta as características elétricas e mecânicas do atuador e as características mecânicas do robô. O projeto de um controlador linear é realizado por meio da alocação dos polos do sistema em malha fechada através da realimentação dos estados de posição e de velocidade angulares do rotor unidos a um integrador do erro de posição angular. Para o primeiro grau de liberdade, por conta da variação do momento de inércia de massa associado a essa junta, um controlador com ganhos parametrizados foi projetado, no qual os ganhos são calculados baseado no modelo matemático relativo ao momento de inércia de massa associado a essa junta. Por meio de simulações computacionais, avaliou-se o projeto dos controladores no movimento ponto a ponto dos cinco eixos de atuação e a variação do momento de inércia de massa sobre a primeira junta. Os resultados dessas simulações mostraram que os controladores propostos cumprem com a dinâmica desejada nos cinco graus de liberdade do robô. / This work contemplates the design of a robotic manipulator, which is operated by a stepper motor with five actuation joints. The robot design steps were divided into: mechanical design; mathematical modeling; controller design; and simulations. The mechanical design presents a proposal of mechanical configuration and sizing that supplies the required demand for the analyzed operation. The mathematical model presents the electrical and mechanical characteristics of the actuator and the mechanical characteristics of the robot. The design of a linear controller is accomplished by allocating the poles of the closed loop system by states feedback of the position and angular speed of the rotor attached to an angular position error integrator. For the first degree of freedom, due to the variation of mass moment of inertia associated with this joint, a controller with parameterized gains was projected, in which the gains are calculated based on the mathematical model related to the mass moment of inertia associated to this joint. By means of computational simulations, we evaluated the design of the controllers in the point-to-point movement of the five actuation joints and the variation of the mass moment of inertia on the first joint. The results of these simulations showed that the proposed controllers comply with the desired dynamics in the robot’s five degrees of freedom.

Escavadeiras hidráulicas são máquinas versáteis, amplamente utilizadas na construção civil e mineração. Máquinas melhores, mais produtivas, eficientes e que oferecem segurança ao operador são uma demanda constante da indústria. Devido a estes fatores, o controle para a automação de uma escavadeira hidráulica tem sido investigado. Este estudo tem o seu foco voltado para o controle do manipulador do equipamento, que é considerado como um dos elementos fundamentais para o desenvolvimento de uma escavadeira automática. Para desenvolver um sistema de controle viável, primeiramente, foi realizado a modelagem matemática dos subsistemas mecânico e hidráulico do manipulador; posteriormente esses modelos foram acoplados para representar a interação dos subsistemas. Todos os modelos desenvolvidos foram comparados com modelos de referência, obtidos a partir de softwares comerciais dedicados a modelagem de sistema dinâmicos. Tendo sido verificado a capacidade de representação física dos modelos, a fase de projeto do controlador para o manipulador foi iniciada. Para que o controlador seja eficiente, este deve ter duas propriedades essenciais: robustez para lidar com as incertezas e distúrbios severos, e adaptabilidade para lidar com um ambiente de operação altamente dinâmico. A fim de projetar um controlador que considera a dinâmica de cada subsistema do manipulador, a técnica de controle em cascata foi adotada. Esta consiste em dividir o sistema global em subsistemas, de tal forma que seja possível projetar um controlador para cada subsistema. Devido à complexidade do modelo matemático, técnicas avançadas de controle linear e não linear foram combinadas no projeto dos controladores dos subsistemas. O controlador sintetizado foi testado através de simulação numérica, em ambiente MATLAB/Simulink®, na execução de um ciclo completo de trabalho pelo manipulador. Os resultados obtidos foram considerados satisfatórios, mesmo na presença de incertezas, distúrbios severos e de ruídos. Posteriormente, na comparação desses resultados com os de outros controladores, ficou claro que o melhor desempenho foi obtido com o controlador proposto. Isto indica a possível aplicabilidade de tal controlador para a automação deste tipo de equipamento. / Hydraulic excavators are versatile machines, widely used in civil construction and in mining. Better, more productive, and efficient machines that offer operator safety are a constant industry demand. Due to these factors, the control for the automation of a hydraulic excavator has been investigated. This study focuses on the control of the equipment\'s manipulator, which is considered as one of the fundamental elements for the development of an automatic excavator. To develop a viable control system, first, the mathematical modeling of the mechanical and hydraulic subsystems of the manip-ulator was carried out; later these models were coupled to represent the interaction between the subsystems. All the developed models were compared with reference models, obtained from a commercial software dedicated to dynamic system modeling. Having verified the physical representation capacity of the analytical models, the de-sign phase of the controller was started. For the controller to be efficient, it must have two essential properties: robustness to deal with severe uncertainties and disturb-ances, and adaptability to handle a highly dynamic operating environment. To design a controller that considers the dynamics of each subsystem of the manipulator, the cascade control technique was adopted. This consists of dividing the global system into subsystems, in such a way that it is possible to design a controller for each sub-system. Due to the complexity of the mathematical model, advanced linear and non-linear control techniques were combined in subsystem controllers design. The synthe-sized controller was tested by numerical simulation, in MATLAB/Simulink® environ-ment, in the execution of a complete work operation by the manipulator. The results obtained were considered satisfactory, even in the presence of uncertainties, severe disturbances and noise. Subsequently, in the comparison of these results with those of others controllers, it was clear that the best performance was obtained with the pro-posed controller. This indicates the possible applicability of such a controller to the automation of this type of equipment.

The purpose of this thesis is to develop a position control method for parallel manipulators so that the end effector can follow a desired trajectory specified in the task space where joint flexibility that occurs at the actuated joints is also taken into consideration. At the beginning of the study, a flexible joint is modeled, and the equations of motion of the parallel manipulators are derived for both actuator variables and joint variables by using the Lagrange formulation under three assumptions regarding dynamic coupling between the links and the actuators. These equations of motion are transformed to an input/output relation between the actuator torques and the actuated joint variables to achieve the trajectory tracking control. Moreover, the singular configurations of the parallel manipulators are explained. As a case study, a three degree of freedom, two legged planar parallel manipulator is simulated considering joint flexibility. The structural damping of the active joints, viscous friction at the passive joints and the rotor damping are also considered throughout the study. Matlab&reg / and Simulink&reg / softwares are used for the simulations. The results of the simulations reveal that steady state errors are negligibly small and good tracking performances can be achieved.

In this thesis, a technique for the motion of parallel manipulators through drive singularities is investigated. To remedy the problem of unbounded inverse dynamics solution in the neighborhood of drive singularities, an inverse dynamics controller which uses a conventional inverse dynamics control law outside the neighborhood of singularities and switches to the mode based on the formerly derived modified equations inside the neighborhood of singularities is proposed. As a result, good tracking performance is obtained while the actuator forces remain within the saturation limits of the actuators around singular configurations.

The hyper redundant manipulators (HRMs) have excessively large degrees of freedom. As a special but practicable subset, the binary HRMs use binary (on-off) actuators with only two stable states such as pneumatic cylinders and solenoids. Such actuators are simple, cheap, and easy to control. Therefore, a binary HRM has been studied in this thesis. The thesis work covers the conceptual design of a spatial binary HRM together with its controlled motion simulations. The manipulator consists of many modules, each of which has the same constructive characteristics and consists of three submodules which are two cascaded variable geometry truss structures working in mutually orthogonal planes and a discrete twister. The manipulator is assumed to be powered with pneumatic on-off actuators. Because of the discrete nature of the binary actuators, a small but continuously actuated manipulator with six degrees of freedom is installed as the last module of the HRM in order to compensate the discretization errors. To solve the inverse kinematics problem of the HRM, three methods have been presented. These are the spline fitting, the extended spline fitting, and the workspace filling methods. The spline fitting method is based on forcing the spine (i.e. the center line) of the manipulator to approximate a spatial reference spline which is specified as a desired curve. In the extended spline fitting method, the result found in the first method is improved by using a genetic algorithm. In the work space filling method, the workspace of the manipulator is filled randomly with a sufficiently large finite number of discrete configurational samples. If it is desired to have concentration on a particular region of the work space, then that region is filled by using a genetic algorithm. After the filling stage, the sample closest to the desired configuration is determined by a suitable search algorithm. Finally, in order to simulate the motion of the HRM between two successive configurational steps, the equations of motions of the HRM are obtained in terms of the pressure forces generated by the binary pneumatic actuators. Then, the necessary simulations are carried out to demonstrate the performance of the HRM in some typical applications.

In dieser Arbeit wurde der Einsatz eines miniaturisierten Endoskop-Manipulator-Systems (EMS [TUM, MiMed, München]) in der endo- und transnasalen Chirurgie untersucht. In einem Modellversuch wurden an einem Nasennebenhöhlenmodell drei typische anatomische Landmarken je einmal manuell und zum Vergleich mit dem Endoskopmanipulator aufgesucht. Insgesamt wurden 240 Messwerte aufgenommen. Es wurden die benötigten Zeiten und die Genauigkeit der Endoskopposition gemessen. Grundlage des klinischen Versuchsteils war es, 31 funktionelle Nasennebenhöhleneingriffe durchzuführen. Dabei wurden die gewählten Endoskoppositionen, die Wechsel der Endoskoppositionen und die konzeptionsbedingten Unterbrechungen erfasst. Als Ausblick für eine Anwendung des EMS bei Operationen erhöhten Schwierigkeitsgrades wurde im Rahmen eines Kadaver-Versuches ein endoskopischer Zugang zur Hypophyse mit dem EMS erprobt. Es konnte weder im Laborversuch noch im klinischen Versuchsteil eine Unterlegenheit beim Einsatz des EMS bezüglich der Dauer und der Genauigkeit der assistierten Endoskopführung festgestellt werden. Die Anzahl der Positionswechsel lag durchschnittlich bei 6,4 pro Seite. Eine beidhändige Instrumentation war in allen untersuchten Fällen möglich, mit Ausnahme von Bereichen mit Hochrisikostruktu-ren (Lamina papyracea, Recessus frontalis), in welchen der Operateur aus Sicherheitsgründen auf eine manuelle Endoskopführung umstellte. Das untersuchte EMS wurde erfolgreich in den chirurgischen Workflow der endo- und transnasalen Chirurgie integriert, wobei die geringe Anzahl der Endoskoppositionswechsel eine beidhändige Instrumentation ermöglichte. Als Entwicklungspotenzial kann die Ergänzung der Joystickkonsole um eine Force-Feedback-Funktion bzw. die Möglichkeit einer rein navigiert-kontrollierten Steuerung hervorgehoben werden. Damit wird die Häufigkeit einer Unterbrechung des Workflows für die händische Steuerung über die Joystickkonsole minimiert.

When a robotic system executes a task, there are a number of responsibilities that belong to either the operator and/or the robot. A more autonomous system has more responsibilities in the completion of a task and must possess the decision making skills necessary to adequately deal with these responsibilities. The system must also handle environmental constraints that limit the region of operability and complicate the execution of tasks. There are decisions about the robot’s internal configuration and how the manipulator should move through space, avoid obstacles, and grasp objects. These motions usually have limits and performance requirements associated with them. Successful completion of tasks in a given environment is aided by knowledge of the robot’s capabilities in its workspace. This not only indicates if a task is possible but can suggest how a task should be completed. In this work, we develop a grasping strategy for selecting and attaining grasp configurations for flexible tasks in environments containing obstacles. This is done by sampling for valid grasping configurations at locations throughout the workspace to generate a task plane. Locations in the task plane that contain more valid configurations are stipulated to have higher dexterity and thus provide greater manipulability of targets. For valid configurations found in the plane, we develop a strategy for selecting which configurations to choose when grasping and/or placing an object at a given location in the workspace. These workspace task planes can also be utilized as a design tool to configure the system around the manipulator’s capabilities. We determine the quality of manipulator positioning in the workspace based on manipulability and locate the best location of targets for manipulation. The knowledge of valid manipulator configurations throughout the workspace can be used to extend the application of task planes to motion planning between grasping configurations. This guides the end-effector through more dexterous workspace regions and to configurations that move the arm away from obstacles. The task plane technique employed here accurately captures a manipulator’s capabilities. Initial tests for exploiting these capabilities for system design and operation were successful, thus demonstrating this method as a viable starting point for incrementally increasing system autonomy. / text

This thesis investigates particular topics in advanced motion control of two distinct mechanical systems: human-like motion control of redundant robot manipulators and advanced sensing and control for energy-efficient operation of electromagnetic devices. Control of robot manipulators for human-like motions has been one of challenging topics in robot control for over half a century. The first part of this thesis considers methods that exploits robot manipulators??? degrees of freedom for such purposes. Jacobian transpose control law is investigated as one of the well-known controllers and sufficient conditions for its universal convergence are derived by using concepts of ???stability on a manifold??? and ???transferability to a sub-manifold???. Firstly, a modification on this method is proposed to enhance the rectilinear trajectory of the robot end-effector. Secondly, an abridged Jacobian controller is proposed that exploits passive control of joints to reduce the attended degrees of freedom of the system. Finally, the application of minimally-attended controller for human-like motion is introduced. Electromagnetic (EM) access control systems are one of growing electronic systems which are used in applications where conventional mechanical locks may not guarantee the expected safety of the peripheral doors of buildings. In the second part of this thesis, an intelligent EM unit is introduced which recruits the selfsensing capability of the original EM block for detection purposes. The proposed EM device optimizes its energy consumption through a control strategy which regulates the supply to the system upon detection of any eminent disturbance. Therefore, it draws a very small current when the full power is not needed. The performance of the proposed control strategy was evaluated based on a standard safety requirement for EM locking mechanisms. For a particular EM model, the proposed method is verified to realize a 75% reduction in the power consumption.