Máquinas manuais são utilizadas em diversos processos, como na usinagem mecânica. Apesar da existência de máquinas automatizadas, com boa precisão e conformidade, as máquinas manuais de usinagem possuem baixo custo inicial e alta flexibilidade de produção, sendo empregadas para produção de lotes pequenos ou peças únicas, como protótipos ou peças empregadas em pesquisas científicas. O operador humano possui mais flexibilidade que qualquer sistema automatizado por ter a capacidade de tomar decisões. O posicionamento da ferramenta de usinagem através de uma mesa linear com parafuso e porca, acionada manualmente com um manípulo, exige perícia do operador e impacta no custo final das peças produzidas. Um dispositivo robótico acoplado ao mecanismo de posicionamento poderia trabalhar em cooperação com o operador humano, sendo utilizado como um recurso optativo para auxiliá-lo na tarefa de posicionamento. Atuadores passivos do tipo freio são seguros para a manipulação humana direta e naturalmente estáveis ao manter uma posição estática, além de baratos e simples. Sendo controlado por computador e com a posição desejada facilmente programável, o freio eliminaria a preocupação do operador com o posicionamento crítico, permitindo concentrar-se em outros detalhes do trabalho de usinagem ao delegar a tarefa de posicionamento ao freio. Literatura ou índices de desempenho escassos e iniciais foram encontrados sobre a utilização de freios neste contexto. Desta forma, este trabalho estuda os mecanismos típicos de máquinas manuais de usinagem e de freios por atrito, propondo então algoritmos de controle e avaliando seu desempenho. Desenvolveu-se dois tipos de controladores para lidar com as fortes não linearidades do atrito e fatores estocásticos do mesmo: um primeiro que utiliza pré-alimentação de um modelo do atuador e um segundo que tenta diminuir a influência de perturbações no posicionamento final diminuindo a velocidade do sistema nas imediações da posição desejada de frenagem. Um protótipo foi montado e permitiu avaliar experimentalmente os algoritmos, que apresentaram bons índices de desempenho que confirmam seu potencial de utilização, baseados em trabalhos anteriores e normas técnicas de tolerâncias gerais. / Manual machines are those with minimum or non-existent automation, being employed in many processes, like in the mechanical machining, where the operator have the task to position a machining tool to manufacture pieces. Despite the existence of automated machines, with good precision and production regularity in its produced pieces, the manual machines has low initial cost and high production flexibility, being used for the production of small or unique batches, like prototypes or pieces for scientific research. The human operator has greater flexibility than any automated system as it has the ability to make decisions. The positioning of the machining tool, thru a linear work table with screw and nut, manually operated by a hand wheel, requires operator skills which impacts the final cost of the manufactured pieces. A robotic device coupled to the positioning mechanism would work in cooperation with the human operator, being used as a resource to help with the task of positioning. Passive actuators, like brakes, are safe for human direct manipulation and naturally stable to maintain a position, despite being simple and cheap. Being computer-controlled, with the desired position easily programmable, the brake would eliminate the operators worry with the positioning task, leaving it to the brake. This work studies typical machine mechanisms of manual machines and friction brakes, leading to the development and evaluation of control algorithms. Two main types of feedback controllers were developed to deal with the brakes hard nonlinearities of friction and stochastic factors: one that uses a feedforward model to compensate for modeled disturbances and a second that tries to lower the disturbances influence by lowering the velocity nearby the desired position. A prototype were built and allowed to experimentally evaluate the proposed algorithms, which presented good performance in relation to early works and tolerance standards.

" Three dimensional travel in immersive virtual environments (IVE) has been a difficult problem since the beginning of virtual reality (VR), basically due to the difficulty of designing an intuitive, efficient, and precise three degrees of freedom (DOF) interface which can map the user's finite local movements in the real world to a potentially infinite virtual space. Inspired by the Silver Surfer Sci-Fi movie and the popularity of the Nintendo Wii Balance Board interface, a surfboard interface appears to be a good solution to this problem. Based on this idea, I designed and developed a VR Silver Surfer system which allows a user to surf in the sky of an infinite virtual environment, using either an isometric balance board or an elastic tilt board. Although the balance board is the industrial standard of board interface, the tilt board seems to provide the user more intuitive, realistic and enjoyable experiences, without any sacrifice of efficiency or precision. To validate this hypothesis we designed and conducted a user study that compared the two board interfaces in three independent experiments that break the travel procedure into separate DOFs. The results showed that in all experiments, the tilt board was not only as efficient and precise as the balance board, but also more intuitive, realistic and fun. In addition, despite the popularity of the balance board in the game industry, most subjects in the study preferred the tilt board in general, and in fact complained that the balance board could have been the cause of possible motion sickness. "

In this thesis, position and current control systems for a brushless DC (Direct Current) motor are designed and integrated into one FPGA (Field Programmable Gate Array) chip. Experimental results are obtained by driving the brushless DC motors of Control Actuation System of a guided missile. Because of their high performance, brushless DC motors are widely used in Control Actuation Systems of guided missiles. In order to control the motor torque, current controller is designed and implemented in the FPGA. Position controller is designed to fulfill the position commands. A soft processor in the FPGA is used to connect and configure the current controller, position sensor interfaces and communication modules such as UART (Universal Asynchronous Receiver Transmitter) and Spacewire. In addition / position controller is implemented in the soft processor in the FPGA. An FPGA based electronic board is designed and manufactured to implement control algorithms, power converter circuitry and to perform other tasks such as communication with PC (Personal Computer). In order to monitor the behavior of the controllers in real time and to achieve performance tests, a graphical user interface is provided.

Abstract This thesis studies on the design of hybrid fuzzy PID controller via genetic algorithms and the position control of linear DC motors. Due to the high precision and high speed positioning ability, linear DC motors have been widely used in many fields. However, with the higher requirements of positioning accuracy, the effect of nonlinear friction becomes very significant. Because of the large difference between dynamic friction in macrodynamic region and static friction in microdynamic region, we design the two-stage controller for positioning in macrodynamic and microdynamic stage individually. In the macrodynamic stage, we use the hybrid fuzzy PID controller and finding the optimal membership functions and scaling factors of the controller via adaptive genetic algorithms to enhance performance of the system. A novel formula for calculating adaptive crossover and mutation rate is also presented. Since it is not easy to establish a precise static friction model in the microdynamic region, the relay feedback method is adopted to design PID controllers. Finally, through computer simulations and experiments, it is obviously that the performance of the proposed controllers is satisfactor

Behrad Dehghan: Position Control of a Pneumatic System using Adaptive Intelligent Methods. M.A.Sc. Thesis, Queen’s University, June, 2012. A large body of research is devoted to the development of advanced control techniques to improve the positioning performance of pneumatic systems, which are known to be highly nonlinear systems. Although model based controllers show good results, the requirement for a system model makes these methods difficult to implement. So-called intelligent algorithms, such as neural networks and fuzzy rule based controllers, are attractive since they do not require a model. The performance of these controllers can be enhanced by adding an adaptive mechanism to adjust controller parameters in a continuous on-line fashion. The objective of this thesis was to explore different adaptive intelligent controllers for position control of a pneumatic system. The application was the x-axis and z-axis of a pneumatic gantry robot. They were tested independently for their ability to track step and sine wave trajectories. The rodded x-axis cylinder was an example of a short stroke low friction application. The rodless z-axis cylinder was an example of a long stroke high friction application. Five different controllers were tested: 1) PID, 2) Fuzzy, 3) PID+Adaptive Neural Network Compensator (ANNC), 4) ANNonly and 5) Fuzzy Adaptive PID (FAPID). Results with FAPID and PID+ANNC showed improvement in tracking performance over PID by 60% for the rodded and 35% for the rodless cylinder. This level of improvement was expected given the adaptive nature of the controller. Unfortunately, both required significant effort to setup and tune. In order to reduce the tuning effort, a second adaptive mechanism was added to FAPID, to adjust output weights. Results with adaptive PID and modified FAPID (MFAPID) showed further improvement performance over PID by 87% for the rodded and 70% for the rodless cylinder (in addition to being easier to tune). To provide a measure of robustness, experiments were conducted at two supply pressures and three tracking frequencies. The fact that MFAPID was able to improve performance for both cylinders, is considered further evidence of its robustness. MFAPID is considered novel for two reasons: 1) fuzzy rule set is reduced in size relative previous work and 2) addition of an adaptive mechanism for output weights is new. / Thesis (Master, Mechanical and Materials Engineering) -- Queen's University, 2012-06-20 11:09:19.694

This Ph.D. thesis presents the design, modeling, optimization, prototyping, and experimental methodologies for a novel actuation system for the synchronized segmentally interchanging pulley transmission system (SSIPTS). The SSIPTS is an improved transmission which offers the combined benefits of existing transmission systems for the automotive, the power generation, and the heating, ventilation, and air conditioning (HVAC) industries. As a major subsystem of the SSIPTS, the Pulley Segment Actuation System (PSAS) plays a critical role in the SSIPTS operation and success. However, the overall design of the SSIPTS and its operation principle introduce very challenging and conflicting design requirements for PSASs that the existing actuation technologies cannot meet. To address the lack of actuation technologies for the PSAS application, this research proposes a unique actuation system that meets all the challenging design requirements of the PSAS. This new actuation system is based on the electromagnetic moving coil actuator (MCA) technology. The proposed system is conceptualized and modeled. The key parameters of the actuation system are defined following the conceptual design and modeling. Further, the geometry mapping optimization and the FEM analysis are conducted to determine the optimized values for the key design parameters. From the simulation results, the optimized actuator is shaped. Moreover, a proper control strategy is proposed for the motion of the actuator. Experiments are performed to find the empirical parameters of the actuator, to validate the proposed design, and to test the performance of the actuator. Experimental results show that the prototype of the actuation system meets the design requirements and is feasible for implementation in the SSIPTS. The main contribution of this thesis is to develop a highly efficient and reliable ultra fast bi-stable actuation system for the PSAS for the SSIPTS. As an ultra fast bistable actuation system, the designed actuation system has many advantages over other types of actuation systems: higher load capacity, smaller dimensions, and good controllability. These performance characteristics make the designed actuation system an excellent candidate in applications requiring fast transient response, high precision, and high load capacity such as electromagnetic valve actuators for engines, high speed pick and place, and precise positioning.

This Ph.D. thesis presents the design, modeling, optimization, prototyping, and experimental methodologies for a novel actuation system for the synchronized segmentally interchanging pulley transmission system (SSIPTS). The SSIPTS is an improved transmission which offers the combined benefits of existing transmission systems for the automotive, the power generation, and the heating, ventilation, and air conditioning (HVAC) industries. As a major subsystem of the SSIPTS, the Pulley Segment Actuation System (PSAS) plays a critical role in the SSIPTS operation and success. However, the overall design of the SSIPTS and its operation principle introduce very challenging and conflicting design requirements for PSASs that the existing actuation technologies cannot meet. To address the lack of actuation technologies for the PSAS application, this research proposes a unique actuation system that meets all the challenging design requirements of the PSAS. This new actuation system is based on the electromagnetic moving coil actuator (MCA) technology. The proposed system is conceptualized and modeled. The key parameters of the actuation system are defined following the conceptual design and modeling. Further, the geometry mapping optimization and the FEM analysis are conducted to determine the optimized values for the key design parameters. From the simulation results, the optimized actuator is shaped. Moreover, a proper control strategy is proposed for the motion of the actuator. Experiments are performed to find the empirical parameters of the actuator, to validate the proposed design, and to test the performance of the actuator. Experimental results show that the prototype of the actuation system meets the design requirements and is feasible for implementation in the SSIPTS. The main contribution of this thesis is to develop a highly efficient and reliable ultra fast bi-stable actuation system for the PSAS for the SSIPTS. As an ultra fast bistable actuation system, the designed actuation system has many advantages over other types of actuation systems: higher load capacity, smaller dimensions, and good controllability. These performance characteristics make the designed actuation system an excellent candidate in applications requiring fast transient response, high precision, and high load capacity such as electromagnetic valve actuators for engines, high speed pick and place, and precise positioning.

Various roles for operators in human-machine systems have been proposed. This thesis shows that all of these views have in common the fact that operators perform best when given feedback that matches their intent. Past studies have shown that position control is superior to rate control except when operating large-workspace and/or dynamically slow manipulators and for exact tracking tasks. Operators of large-workspace and/or dynamically slow manipulators do not receive immediate position feedback. To remedy this lack of position feedback, a ghost arm overlay was displayed to operators of a dynamically slow manipulator, giving feedback that matches their intent. Operators performed several simple one- and two-dimensional tasks (point-to-point motion, tracking, path following) with three different controllers (position control with and without a ghost, rate control) to indicate how task conditions influence operator intent. Giving the operator position feedback via the ghost significantly increased performance with the position controller and made it comparable to performance with the rate control. These results were further validated by testing coordinated position control with and without a ghost arm and coordinated rate control on an excavator simulator. The results show that position control with the ghost arm is comparable, but not superior to rate control for the dynamics of our excavator example. Unlike previous work, this research compared the fuel efficiencies of different HMIs, as well as the time efficiencies. This work not only provides the design law of matching the feedback to the operator intent, but also gives a guideline for when to choose position or rate control based on the speed of the system.

Made available in DSpace on 2015-05-08T15:00:01Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 3802026 bytes, checksum: a4d2c7c653bac2c5343accc2b54bfc46 (MD5) Previous issue date: 2010-04-05 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / This work presents the project of fuzzy controllers for a X-Y coordinate table with two degrees of freedom. Both bases of the table moves horizontally, powered by tree-phases induction motors operated by frequency inverts. For detection position of bases, optical encoders were engaged to the axes of the engines to be obtained the angular displacement. A data acquisition board made the interface between a 1.4 GHz Pentium computer and the system. This board catches signals from the encoders and provides control signals to the frequency inverters. Fuzzy controllers, implemented im LabVIEM® software, determinate the control variables to power the engines. Step, sine and cosine reference were used to evaluate the system performance, in position control and following trajectory. Experimental results are presented. / No presente trabalho apresenta-se um projeto de controladores fuzzy para uma mesa de coordenadas X-Y com dois graus de liberdade. Ambas as bases que compõem a mesa se deslocam horizontalmente, sendo acionadas por motores de indução trifásicas alimentados através de inversores de frequência. Para a detecção de posição das bases, encoders ópticos foram acoplados aos eixos dos motores, a fim de serem obtidos os deslocamentos angulares desses últimos. Uma placa de aquisição de dados realizou a interface entre um computador Pentium 1,4 GHz e a planta, para captar os sinais provenientes dos encoders e fornecer os sinais de controle aos inversores de frequência. No ambiente de programação LabVIEW®, implementaram-se os controladores fuzzy, os quais determinam as variáveis de controle que acionam os motores. Sinais de referência do tipo degrau, senoidal e cosenoidal foram utilizados para a avaliação do desempenho do sistema, no controle de posição e acompanhamento de trajetória. Resultados experimentais são apresentados.

Made available in DSpace on 2015-05-08T15:00:06Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 1366150 bytes, checksum: 91eeeb49bf7b5f1a1e12de73985e1fa1 (MD5) Previous issue date: 2011-02-24 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / This work presents the design of neural controllers for a X-Y table with two degrees of freedom. Both bases of the table moves horizontally, powered by tree-phases induction motors operated by frequency inverters. For detection position of bases, optical encoders were engaged to the axes of the engines to be obtained the angular displacement. A data acquisition board made the interface between a 2.4 GHz Core2Duo computer and the system. This board catches signals from the encoders and provides control signals to the frequency inverters. Neural controllers implemented in LabVIEW® software, determinate the control variables to power the engines. Step, sine and cosine reference were used to evaluate the system performance, in position control and following trajectory. Experimental results are presented. / No presente trabalho apresenta-se um projeto de controladores neurais para uma mesa de coordenadas X-Y com dois graus de liberdade. Ambas as bases que compõem a mesa se deslocam horizontalmente, sendo acionadas por motores de indução trifásicos alimentados através de inversores de freqüência. Para a detecção de posição das bases, encoders ópticos foram acoplados aos eixos dos motores, a fim de serem obtidos os deslocamentos angulares desses últimos. Uma placa de aquisição de dados realizou a interface entre um computador Core2Duo 2,4 GHz e a planta, para captar os sinais provenientes dos encoders e fornecer os sinais de controle aos inversores de frequência. No ambiente de programação LabVIEW®, implementaram-se os controladores neurais, os quais determinam as variáveis de controle que acionam os motores. Sinais de referência do tipo degrau e acompanhamento de trajetória foram utilizados para a avaliação do desempenho do sistema. Resultados experimentais são apresentados.