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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Steering Of Redundant Robotic Manipulators And Spacecraft Integrated Power And Attitude Control - Control Moment Gyroscopes

Altay, Alkan 01 January 2006 (has links) (PDF)
In this thesis, recently developed Blended Inverse (B-inverse) steering law is applied to two different redundant actuator systems. First, repeatability of Binverse is demonstrated on a redundant robotic manipulator. Its singularity avoidance and singularity transition performance is also demonstrated on the same actuator system. It is shown that B-inverse steering law provides singularity avoidance, singularity transition and repeatability. Second, its effectiveness is demonstrated for an Integrated Power and Attitude Control - Control Moment Gyroscope (IPAC-CMG) cluster, which can perform energy management and attitude control functions simultaneously. For this purpose, an IPAC-CMG flywheel is conceptually designed. A control policy is developed for the energy management.
42

Mapeamento da cinemática inversa de um manipulador robótico utilizando redes neurais artificiais configuradas em paralelo / Mapping the inverse kinematics of a robot manipulator using artificial neural networks configured in parallel

Nunes, Ricardo Fernando [UNESP] 31 March 2016 (has links)
Submitted by RICARDO FERNANDO NUNES null (ricardofnes@gmail.com) on 2016-05-09T19:20:22Z No. of bitstreams: 1 Ricardo_Nunes_Pos_Defesa_FINAL.pdf: 4578185 bytes, checksum: 7d5f2601e5d33327aef16ab69587d77f (MD5) / Approved for entry into archive by Felipe Augusto Arakaki (arakaki@reitoria.unesp.br) on 2016-05-12T19:25:25Z (GMT) No. of bitstreams: 1 nunes_rf_me_ilha.pdf: 4578185 bytes, checksum: 7d5f2601e5d33327aef16ab69587d77f (MD5) / Made available in DSpace on 2016-05-12T19:25:25Z (GMT). No. of bitstreams: 1 nunes_rf_me_ilha.pdf: 4578185 bytes, checksum: 7d5f2601e5d33327aef16ab69587d77f (MD5) Previous issue date: 2016-03-31 / Neste trabalho apresenta-se uma abordagem para o mapeamento da cinemática inversa utilizando Redes Neurais Artificiais do tipo Perceptron Multicamadas na configuração em paralelo, tendo como referência o protótipo de um manipulador robótico de 5 graus de liberdade, composto por sete servomotores controlado pela plataforma de desenvolvimento Intel® Galileo Gen 2. As equações da cinemática inversa, normalmente apresentam múltiplas soluções, desta forma, uma solução interessante e frequentemente encontrada na literatura são as Redes Neurais Artificiais (RNA) em razão da sua flexibilidade e capacidade de aprendizado por meio do treinamento. As Redes Neurais são capazes de entender a relação cinemática entre o sistema de coordenadas das juntas e a posição final da ferramenta do manipulador. Para avaliar a eficiência do método proposto foram realizadas simulações no software MATLAB, as quais demostram pelos resultados obtidos e comparações a uma RNA do tipo MLP simples, aproximadamente redução das médias dos erros das juntas em até 87,8% quando aplicado à trajetória e 80% quando aplicado a pontos distribuídos no volume de trabalho. / This paper presents an approach to the mapping of inverse kinematics using Artificial Neural Networks Multilayer Perceptron in parallel configuration, in the prototype of a robotic manipulator 5 degrees of freedom, as reference, composed of seven servomotors controlled by development board Intel® Galileo Gen 2. The equations of inverse kinematics, usually have multiple solutions, therefore, an interesting solution and often found in the literature are the Artificial Neural Networks (ANN) because of their flexibility and learning capacity through training. Neural Networks are able to understand the kinematic relationship between the coordinate system of the joints and the final position of the manipulator tool. To evaluate the efficiency of the proposed, simulations in MATLAB software are performaded, that demonstrate by the results obtained and compared to a simple MLP type RNA, one reduction in mean errors of the joints by up to 87.8% when applied to the path and 80% when applied to points distributed in the work space.
43

Mapeamento da cinemática inversa de um manipulador robótico utilizando redes neurais artificiais configuradas em paralelo /

Nunes, Ricardo Fernando January 2016 (has links)
Orientador: Suely Cunha Amaro Mantovani / Resumo: Neste trabalho apresenta-se uma abordagem para o mapeamento da cinemática inversa utilizando Redes Neurais Artificiais do tipo Perceptron Multicamadas na configuração em paralelo, tendo como referência o protótipo de um manipulador robótico de 5 graus de liberdade, composto por sete servomotores controlado pela plataforma de desenvolvimento Intel® Galileo Gen 2. As equações da cinemática inversa, normalmente apresentam múltiplas soluções, desta forma, uma solução interessante e frequentemente encontrada na literatura são as Redes Neurais Artificiais (RNA) em razão da sua flexibilidade e capacidade de aprendizado por meio do treinamento. As Redes Neurais são capazes de entender a relação cinemática entre o sistema de coordenadas das juntas e a posição final da ferramenta do manipulador. Para avaliar a eficiência do método proposto foram realizadas simulações no software MATLAB, as quais demostram pelos resultados obtidos e comparações a uma RNA do tipo MLP simples, aproximadamente redução das médias dos erros das juntas em até 87,8% quando aplicado à trajetória e 80% quando aplicado a pontos distribuídos no volume de trabalho. / Abstract: This paper presents an approach to the mapping of inverse kinematics using Artificial Neural Networks Multilayer Perceptron in parallel configuration, in the prototype of a robotic manipulator 5 degrees of freedom, as reference, composed of seven servomotors controlled by development board Intel® Galileo Gen 2. The equations of inverse kinematics, usually have multiple solutions, therefore, an interesting solution and often found in the literature are the Artificial Neural Networks (ANN) because of their flexibility and learning capacity through training. Neural Networks are able to understand the kinematic relationship between the coordinate system of the joints and the final position of the manipulator tool. To evaluate the efficiency of the proposed, simulations in MATLAB software are performaded, that demonstrate by the results obtained and compared to a simple MLP type RNA, one reduction in mean errors of the joints by up to 87.8% when applied to the path and 80% when applied to points distributed in the work space. / Mestre
44

Local models for inverse kinematics approximation of redundant robots: a performance comparison / Modelos locais para aproximaÃÃo da cinemÃtica inversa de robÃs redundantes: um estudo comparativo

Humberto Ãcaro Pinto Fontinele 04 December 2015 (has links)
nÃo hà / In this dissertation it is reported the results of a comprehensive comparative study involving six local models applied to the task of learning the inverse kinematics of three redundant robotic arm (planar, PUMA 560 and Motoman HP6). The evaluated algorithms are the following ones: radial basis functions network (RBFN), local model network (LMN), SOMbased local linear mapping (LLM), local linear mapping over k-winners (K-SOM), local weighted regression (LWR) and counter propagation (CP). Each algorithm is evaluated with respect to its accuracy in estimating the joint angles given the cartesian coordinates which comprise end-effector trajectories within the robot workspace. A comprehensive evaluation of the performances of the aforementioned algorithms is carried out based on correlation analysis of the residuals. Finally, hypothesis testing procedures are also executed in order to verifying if there are significant differences in performance among the best algorithms. / Nesta dissertaÃÃo sÃo reportados os resultados de um amplo estudo comparativo envolvendo seis modelos locais aplicados à tarefa de aproximaÃÃo do modelo cinemÃtico inverso de 3 robÃs manipuladores (planar, PUMA 560 e Motoman HP6). Os modelos avaliados sÃo os seguintes: rede de funÃÃes de base radial (RBFN), rede de modelos locais (LMN), mapeamento linear local baseado em SOM (LLM), mapeamento linear local usando K vencedores (KSOM), regressÃo local ponderada (LWR) e rede counterpropagation (CP). Estes algoritmos sÃo avaliados quanto à acurÃcia na estimaÃÃo dos Ãngulos das juntas dos robÃs manipuladores em experimentos envolvendo a geraÃÃo de vÃrios tipos de trajetÃrias no espaÃo de trabalho dos referidos robÃs. Uma avaliaÃÃo abrangente do desempenho de cada algoritmo à feita com base na anÃlise dos resÃduos e testes de hipÃteses sÃo realizados para verificar a semelhanÃa estatistica entre os desempenhos dos melhores algoritmos.
45

Estudo e implementação de um método de cinemática inversa baseado em busca heurística para robôs manipuladores = aplicação em robôs redundantes e controle servo visual / Heuristic search based inverse kinematics for robotic manipulators : application to redundant robots and visual servoing

Nicolato, Fabricio 06 January 2007 (has links)
Orientador: Marconi Kolm Madrid / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação / Made available in DSpace on 2018-08-15T23:54:05Z (GMT). No. of bitstreams: 1 Nicolato_Fabricio_D.pdf: 1516280 bytes, checksum: 96229803f3bca54f669d4dcc22108c02 (MD5) Previous issue date: 2007 / Resumo: Esta tese trata o problema da resolução do modelo cinemático inverso para manipuladores industriais redundantes ou não. O problema foi abordado por um método de busca heurística no qual a solução da cinemática inversa é construída passo a passo calculando-se a contribuição do movimento de apenas uma junta a cada iteração. Dessa forma, o problema n-dimensional é transformado em problemas unidimensionais mais simples, cuja solução analítica tanto para juntas rotacionais quanto para juntas prismáticas é apresentada em termos da representação de Denavit-Hartenberg. O método proposto não possui singularidades internas. Além disso, o método foi expandido para incorporar informações de sensores externos visando fazer com que o processo seja mais robusto a incertezas nas modelagens envolvidas. Foram realizadas diversas simulações e comparações com técnicas tradicionais que evidenciaram as vantagens da abordagem proposta. O trabalho também englobou o projeto e a construção de um ambiente experimental e a implementação das técnicas desenvolvidas na parte teórica. Desenvolveu-se um sistema com um robô planar redundante de 3 DOF, assim como seus sistemas de controle, acionamento e interfaceamento usando técnicas de sistemas hardware-inthe-loop e lógica programável. As técnicas desenvolvidas foram aplicadas no ambiente experimental demonstrando características como: facilidade de lidar com redundâncias, capacidade de resolução em tempo real, robustez a incertezas de parâmetros etc / Abstract: This thesis deals with the problem of solving the inverse kinematics model of redundant and nonredundant industrial manipulators. The work was developed in a theoretical and a practical part. The problem was approached by an heuristic search method in which the solution of the inverse kinematics is built step by step calculating the movement contribution of just a single joint for each iteration. In that way, the n-dimensional problem is transformed in simpler one-dimensional problems, whose analytic solution for both rotational joints and prismatic joints is presented in terms of the Denavit and Hartenberg representation. The proposed method does not possess internal singularities. Furthermore, the method was expanded to incorporate information of external sensor in order to make the process more robust to uncertainties in the involved modelings. Several results of simulations and comparisons with traditional techniques, which evidence the advantages of the proposed approach, are presented. The work also included the construction of an experimental environment and the implementation of the techniques developed in the theoretical part. The details of a system with a 3-DOF redundant robot as well as its control system, drivers and interfaces using hardware-in-theloop techniques and programmable logic are presented. The developed techniques were applied in the experimental environment are demonstrating their efficiency and evidencing characteristics like: easiness of dealing with redundancies, real time capacity, robustness for parameters uncertainties etc / Doutorado / Automação
46

Procedurální animace lidské chůze / Procedural Animation of Human Walk

Mohelník, Petr January 2016 (has links)
Animation of human walk is employed in many interactive applications, mostly in computer games. There are many ways to create such animation which differ in compromise among naturalness, control over animation and computing time. This work implements procedural animation which is applicable for walking on uneven terrain. Skeletal animation is used for manipulation with model of human body. Furthermore, inverse kinematics is described and implemented. That allows for adaptation to uneven terrain. It also describes phases of human walk, so we can accurately aproximate them. Proposed solution enables specification of walk using number of parameters and is able to adapt to surrounding terrain. The result should be usable in creation of computer games and should allow for creation of specific animation of human walk without need to create such animation manually.
47

Linear Position Tracking for Controlling a Robotic Arm Using Inertial Sensors : Development of a Robotic Arm and an Inertial Sensor-Based Tracking System / Linjär positionsspårning för att styra en robotarm med hjälp av inertiella sensorer : Utveckling av en robotarm och ett inertiell-sensorbaserat spårningssystem

Knobe, Jesper, Pekola, Tobias January 2023 (has links)
In the field of mechatronics, different types of robotic arms are used for various applications. Control of robotic arms from a distance is required in certain situations, such as hazardous environments. The purpose of this thesis was to investigate the feasibility, speed, and accuracy of the movement of a robotic arm following the movement of one handheld Inertial Measuring Unit (IMU). The assessment of accuracy was determined through experiments with pre-established movements and examined responses from the arm. The robot arm has four degrees of freedom and is controlled by integrating and filtering the IMU data to obtain the linear position, and inverse kinematics are used to obtain the arm joint angles required to reach the position. The robotic arm was constructed using Solid Edge 3D CAD, 3D printed in PLA plastic. After construction electronic components were connected and assembled. The programs were implemented in MATLAB, and the data was processed and transferred through the Arduino Integrated Development Environment (IDE). The results indicate that the robotic arm demonstrates good capability in executing given coordinates. The accuracy of the IMU-based position tracking is inconsistent and not suitable for all applications. The system's total speed for reading and executing movements is found to be satisfactory, but improvements in precision are necessary for more demanding implementations. The primary causes of errors in the system are attributed to the precision of the measuring device, manufacturing deviations, and limitations in the IMU calculation. This study contributes to the understanding of linear position tracking using inertial sensors, filtering techniques, and communication between microcontrollers, providing insights for future research and development in the field. / Inom området mekatronik används olika typer av robotarmar för olika tillämpningar. Kontroll av robotarmar på avstånd krävs i situationer som farliga miljöer. Syftet med denna avhandling var att undersöka genomförbarhet, hastighet och rörelseprecision hos en robotarm som följer rörelsen av en handhållen tröghetsmätningsenhet (IMU). Bedömningen av noggrannheten fastställdes genom experiment med förutbestämda rörelser och undersökta svar från armen. Robotarmen har fyra frihetsgrader och styrs genom att integrera och filtrera IMU-data för att erhålla den linjära positionen, och inverskinematik används för att erhålla de nödvändiga armledsvinklarna för att nå positionen. Robotarmen konstruerades med hjälp av Solid Edge 3D CAD, 3D-utskrivet i PLA-plast och elektroniska komponenter monterades. Programmen implementerades i MATLAB och data bearbetades och överfördes via Arduino Integrated Development Environment. Resultaten visar att robotarmen har god förmåga att utföra givna koordinater, men noggrannheten i IMU-baserad positionsspårning är inkonsekvent och inte lämplig för alla tillämpningar. Systemets totala hastighet för att läsa av och utföra rörelser anses vara tillfredsställande, men förbättringar av precisionen är nödvändiga för mer krävande implementeringar. De främsta orsakerna till fel i systemet tillskrivs precisionen hos mätinstrumentet, tillverkningsavvikelser och begränsningar i IMU-beräkningen. Denna studie bidrar till förståelsen av linjär positionsspårning med tröghetssensorer, filtreringstekniker och kommunikation mellan mikrokontroller, vilket ger insikter för framtida forskning och utveckling inom området.
48

HEXA: Hazardous EnvironmenteXpedition Apparatus : Design of a multi-terrain hexapodal robot that utilizes sensory feedback / HEXA: Hazardous Environment eXpedition Apparatus : Design av en flerterränggående hexapodal robot som använder sig av sensor återkoppling

Backne-Genborg, Linus, Hamberg, Viggo January 2022 (has links)
Many hexapods and other robots struggle with walking in uneven terrain, this is due to their lack of sensory feedback. This is the problem aimed to be solved by introducing a sensory feedback loop that measures the current over the servos. By doing this one could know whether or not the leg is in contact with the ground. If a successful sensor can be made, this method could be implemented on any hexapod that uses servos and inverse kinematics for their locomotion to enable them to walk in uneven terrain. With the complete system in place most of what was expected from the system was achieved. HEXA can indeed walk in uneven terrain where the terrain had the maximum height difference of ±2.3 cm, as seen in the video linked in appendix B. It also can detect when a leg has contact with the ground but due to low servo quality the walking could not be tested to its full extent. / Många hexapoder och andra robotar har svårigheter att gå i ojämn terräng, detta är på grund av hur de inte har någon form av senosoråterkoppling. Detta är problemet som siktas på att lösas genom att introducera en sensor återkopplings slinga som mäter stömmen över de olika servon. Genom att implementera detta kan en få reda på om benet har kontakt med marken eller ej. Om en lyckas senor kan skapas, skulle denna metod kunna implementeras till vilken annan hexapodal robot som använder sig av servos och inverse kinematik för sin framdriving. Med det kompletta systemet integrerat uppfylls nästan allt som var förväntad. HEXA kan gå i en ojämn terräng med den maximala höjdsillnaden av ±2.3 cm, som sett i videon i appendix B. Samt kan den märka av när ett av benen är i marken, men på grund av den låga servokvaliteten kunde inte gången testas till sin fulla förmåga.
49

Distribution of Essential Tremor in the Degrees of Freedom of the Upper Limb

Pigg, Adam Charles 01 September 2017 (has links)
This study seeks to understand upper limb tremor in subjects with essential tremor (ET). A thorough understanding of tremor distribution will allow for the more effective development of tremor suppression devices, which offer an alternative to current treatments. Previous studies primarily focused on tremor in the hand only. This study seeks to characterize the distribution of tremor throughout the upper limb.We measured tremor in 25 subjects diagnosed with ET using motion capture, which provided displacement information of the limb during multiple postural and kinetic tasks. Inverse kinematics allowed us to analyze the motion capture data in the 7 major degrees of freedom (DOF) of the upper limb. The power spectral density estimate was used to determine: relative tremor magnitude throughout the DOFs, tremor variation between tasks, variation between subjects, and frequency variations between DOFs. Data analysis revealed that tremor increase is roughly proximal to distal. We also show that tremor magnitude in kinetic tasks is significantly higher than in postural tasks. Although we found some variation in tremor distribution between subjects, the roughly proximal to distal increase in tremor severity holds for several subsets of the study population. Finally, we found that tremor frequency doesnt vary significantly (< 1 Hz) between DOFs, in subjects with severe tremor. Our study shows that tremor distribution is quite stereotyped between subjects with ET. Furthermore, we have shown that tremor is greatest in the distal DOFs. This provides a compelling starting point for the development of future tremor suppression devices.
50

Complete Path Planning of Higher DOF Manipulators in Human Like Environments

Ananthanarayanan, Hariharan Sankara January 2015 (has links)
No description available.

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