The purpose of this research was to determine the feasibility of a laser-based positioning system as a primary navigation method. The system developed for this research consisted of an automated guided vehicle which navigated solely with the use of the laser-based positioning system in real-time. To date, there are no systems which can navigate a pre-defined path using such a positioning system. Some lessons were learned by the researcher, however, concerning the viability of this system in an industrial environment. The system should have had the following advantages over previous systems: 1) Greater range, 2) no prior structuring of environment, 3) real-time navigation, and 4) no reliance on dead-reckoning for navigation. The results showed that goals two through four had been met and are advantages of this system over current systems. The range of this system is limited, however, but it is believed that the next generation system should have greater range than the system used in this research. / Master of Science

No description available.

Thesis (M.S.)--Rochester Institute of Technology, 2008. / Typescript. Includes bibliographical references (leaves 62-63).

A Flexible Manufacturing System (FMS) is an integrated system consisting of several automated work centers interconnected by an automated material handling system. An integrated scheduling methodology is required to schedule all FMS sub-systems. The overall objective of this research was to develop a scheduling methodology to integrate job sequencing and Automatic Guided Vehicle System dispatching within a FMS environment. To develop the new scheduling methodology, the currently used AGVS controller decision set was examined and expanded. The expanded decision set gives the AGVS controller more options to choose from when scheduling the AGVS. The developed integrated scheduling methodology contains four steps. The first step determines which job is to be processed next by each work center based on job sequencing heuristics. The second step determines which work center is to be serviced next by the AGVS based on the estimated time till the work center is forced to stop production. The third step determines which specific job is to be serviced next by the AGVS by combining the work centers' processing orders and the work center servicing priorities. The fourth step decides which AGV is to transport the job requiring immediate service. Based on the preliminary study of a fictitious FMS, the new scheduling methodology showed a statistically significant increase in total job throughput, and a significant decrease in average flow time. Work center utilization also increased. A slight increase in unloaded AGV travel time was found, but was outweighed by the other benefits. / Master of Science

The purpose of this research was to develop and validate a simulation framework for automated guided vehicle systems (AGVSs). The framework that was developed, AGVSF, uses the discrete, next-event simulation method and the C programming language. AGVSF consists of an organizational structure that provides for control of the execution of the simulation and a set of modular C functions used to model the AGVS. The structure of AGVSF allows the user to organize the Simulation logic in a consistent manner. The modularity and flexibility of the code result from clearly defining the interdependencies of the functions that make up the various events and operations of the simulation. This enables the user to substitute functions where needed to represent new operational methods which are not directly provided in the original framework code set. A set of functions is provided within AGVSF for modeling basic AGVSs and AGVS layouts. The framework concept has been validated by simulating an AGVS under different operating conditions and control algorithms. / Master of Science

This research identifies the attributes to be considered in the selection of an automated guided vehicle (AGV). A distinction is made between automated guided vehicles (AGVs) and an automated guided vehicle system (AGVS). This research is concerned only with the selection of automated guided vehicles (AGVs). A selection model is developed which forces the user to evaluate attributes. his requirements and preferences for AGV The first step of the model allows the user to enter his specifications for AGV attributes which are applicable to his production environment. The second step in the selection model is for the user to determine 8-15 attributes to use as selection criteria. In the third phase, the user inputs his preferences and priorities with respect to the attributes chosen as selection criteria in the second step. model ranks the Based on this information, the selection AGV models in the feasible set. A description of the model and a numerical example are included. Steps 1 and 2, described above, are implemented using an R:BASE™ program. The BASIC computer language was used to perform the interrogation of the user with respect to his priorities and preferences among attributes in Step 3. The IBM PC™ is the hardware chosen for running the selection model. / M.S.

Thesis (M. Tech. (Engineering: Electrical)) -- Central University of technology, Free State, 2013 / Automatic Guided Vehicles (AGVs) are being used more frequently in a manufacturing environment. These AGVs are navigated in many different ways, utilising multiple types of sensors for detecting the environment like distance, obstacles, and a set route. Different algorithms or methods are then used to utilise this environmental information for navigation purposes applied onto the AGV for control purposes. Developing a platform that could be easily reconfigured in alternative route applications utilising vision was one of the aims of the research. In this research such sensors detecting the environment was replaced and/or minimised by the use of a single, omnidirectional Webcam picture stream utilising an own developed mirror and Perspex tube setup. The area of interest in each frame was extracted saving on computational recourses and time. By utilising image processing, the vehicle was navigated on a predetermined route. Different edge detection methods and segmentation methods were investigated on this vision signal for route and sign navigation. Prewitt edge detection was eventually implemented, Hough transfers used for border detection and Kalman filtering for minimising border detected noise for staying on the navigated route. Reconfigurability was added to the route layout by coloured signs incorporated in the navigation process. The result was the manipulation of a number of AGV’s, each on its own designated coloured signed route. This route could be reconfigured by the operator with no programming alteration or intervention. The YCbCr colour space signal was implemented in detecting specific control signs for alternative colour route navigation. The result was used generating commands to control the AGV through serial commands sent on a laptop’s Universal Serial Bus (USB) port with a PIC microcontroller interface board controlling the motors by means of pulse width modulation (PWM). A total MATLAB® software development platform was utilised by implementing written M-files, Simulink® models, masked function blocks and .mat files for sourcing the workspace variables and generating executable files. This continuous development system lends itself to speedy evaluation and implementation of image processing options on the AGV. All the work done in the thesis was validated by simulations using actual data and by physical experimentation.

Thesis (M. Tech. (Engineering: Electrical)) -- Central University of technology, Free State, 2013 / In the industry, automation is used to optimize production, improve product quality and increase profitability. By properly implementing automation systems, the risk of injury to workers can be minimized. Robots are used in many low-level tasks to perform repetitive, undesirable or dangerous work. Robots can perform a task with higher precision and accuracy to lower errors and waste of material. Machine Vision makes use of cameras, lighting and software to do visual inspections that a human would normally do. Machine Vision is useful in application where repeatability, high speed and accuracy are important. This study concentrates on the development of a dedicated robot vision system to automatically place components exiting from a conveyor system onto Automatic Guided Vehicles (AGV). A personal computer (PC) controls the automated system. Software modules were developed to do image processing for the Machine Vision system as well as software to control a Cartesian robot. These modules were integrated to work in a real-time system. The vision system is used to determine the parts‟ position and orientation. The orientation data are used to rotate a gripper and the position data are used by the Cartesian robot to position the gripper over the part. Hardware for the control of the gripper, pneumatics and safety systems were developed. The automated system‟s hardware was integrated by the use of the different communication protocols, namely DeviceNet (Cartesian robot), RS-232 (gripper) and Firewire (camera).

Orientador: Fernando Jose Von Zuben / Acompanha CD-ROM / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação / Made available in DSpace on 2018-08-13T02:48:36Z (GMT). No. of bitstreams: 1 Cazangi_RenatoReder_D.pdf: 8716830 bytes, checksum: 272657e08f1aeb5622ebeb4412c49048 (MD5) Previous issue date: 2008 / Resumo: Novas técnicas de navegação autônoma de robôs móveis visam suprir a crescente demanda pelo emprego de robôs em diversos setores da sociedade e junto a uma ampla gama de tarefas. Os desafios envolvidos no desenvolvimento do sistema que controla o robô permitem afirmar que a inteligência embarcada em robôs atuais ainda encontra-se em um nível incipiente e limitado. Neste trabalho, cinco frentes de pesquisa complementares são propostas visando estudar, teórica e praticamente, aspectos fundamentais de projeto e implementação de controladores autônomos inteligentes para robótica móvel. Metodologias de computação bio-inspirada e de robótica evolutiva provêem os conceitos e ferramentas que fundamentam as cinco propostas, as quais são validadas com base em sistemas de navegação concebidos e aplicados a problemas relevantes da área. Uma série de simulações computacionais em ambientes virtuais e experimentos com robôs reais é realizada, permitindo medir o alcance das contribuições e apontar as principais frentes de atuação que se abrem como perspectivas futuras da pesquisa. / Abstract: Novel techniques for autonomous robot navigation aim at fulfilling the growing demand for mobile robots in multiple segments of society and in a plethora of tasks. The challenges involved in developing the system which controls the robot allow to say that the intelligence embedded in the current robots is found to be still incipient and limited. In this work, five complementary research fronts are proposed intending to study, theoretical and practically, aspects which are fundamental to the design and implementation of intelligent autonomous controllers for mobile robotics. Bio-inspired computing and evolutionary robotics methodologies provide the concepts and tools underlying the five proposals, which are validated through navigation systems devised and applied to important problems. Numerous real robot experiments as well as computational simulations taking place in virtual environments are carried out, allowing for the evaluation of contributions and also the discussion of future possibilities. / Doutorado / Engenharia de Computação / Doutor em Engenharia Elétrica

Orientador: Fernando José Von Zuben / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de Computação / Made available in DSpace on 2018-08-18T14:21:13Z (GMT). No. of bitstreams: 1 Azzolini_AlissonGusatti_M.pdf: 3567259 bytes, checksum: 633eb00350cdfa625d0e628fdf1f247e (MD5) Previous issue date: 2011 / Resumo: Há uma demanda crescente por soluções avançadas de navegação autônoma em robótica móvel. Apresenta-se então um sistema de síntese e aprendizagem de controladores com tal finalidade. Propõe-se um controlador probabilístico, consistindo no acoplamento de um processo de decisão de Markov parcialmente observável (POMDP) com um classificador logístico multinomial. A parametrização empregada para o POMDP inspira-se numa proposta anterior de controle de robô por meio de redes imunológicas artificiais, que mostrou apresentar flexibilidade e capacidade de representação de conhecimento na execução de tarefas desafiadoras de navegação autônoma. A aprendizagem dos parâmetros do classificador logístico é efetuada através de um algoritmo de aprendizagem por reforço baseado em gradiente de política, e os do POMDP, atráves de um algoritmo de maximização de verossimilhança. Três experimentos computacionais são efetuados, dois deles utilizando somente o classificador logístico, e o terceiro utilizando o acoplamento entre POMDP e classificador logístico. Os resultados permitem a constatação de pontos fortes e algumas deficiências das duas abordagens. O trabalho aponta também para uma potencial reinterpretação do controlador baseado em rede imunológica em termos de um modelo probabilístico similar ao proposto / Abstract: There is an increasing demand for advanced solutions in autonomous navigation of mobile robots. A system is presented for the synthesis and learning of controllers for such purpose. A probabilistic controller is proposed, consisting of the coupling of a partially observable Markov decision process (POMDP) with a multinomial logistic classifier. The parametrization used for the POMDP draws on an earlier proposal of robot control based on artificial immune networks, that has shown to present flexibility and knowledge representation capability in the execution of challenging autonomous navigation tasks. Learning the logistic classifier parameters is accomplished through a reinforcement learning algorithm based on policy gradient, while the POMDP parameters are learned by a likelihood maximization algorithm. Three computational experiments are performed, two of them using only the logistic classifier, and the third one using the coupling of a POMDP with a logistic classifier. The results show some strong points and drawbacks of both approaches. The work also points torwards a potential reinterpretation of the immune network based controller in terms of a probabilistic model similar to the one proposed / Mestrado / Engenharia de Computação / Mestre em Engenharia Elétrica