A current challenge in neuroscience and systems biology is to better understand properties that allow organisms to exhibit and sustain appropriate behaviours despite the effects of perturbations (behavioural robustness). There are still significant theoretical difficulties in this endeavour, mainly due to the context-dependent nature of the problem. Biological robustness, in general, is considered in the literature as a property that emerges from the internal structure of organisms, rather than being a dynamical phenomenon involving agent-internal controls, the organism body, and the environment. Our hypothesis is that the capacity for behavioural robustness is rooted in dynamical processes that are distributed between agent ‘brain', body, and environment, rather than warranted exclusively by organisms' internal mechanisms. Distribution is operationally defined here based on perturbation analyses. Evolutionary Robotics (ER) techniques are used here to construct four computational models to study behavioural robustness from a systemic perspective. Dynamical systems theory provides the conceptual framework for these investigations. The first model evolves situated agents in a goalseeking scenario in the presence of neural noise perturbations. Results suggest that evolution implicitly selects neural systems that are noise-resistant during coupling behaviour by concentrating search in regions of the fitness landscape that retain functionality for goal approaching. The second model evolves situated, dynamically limited agents exhibiting minimalcognitive behaviour (categorization task). Results indicate a small but significant tendency toward better performance under most types of perturbations by agents showing further cognitivebehavioural dependency on their environments. The third model evolves experience-dependent robust behaviour in embodied, one-legged walking agents. Evidence suggests that robustness is rooted in both internal and external dynamics, but robust motion emerges always from the systemin-coupling. The fourth model implements a historically dependent, mobile-object tracking task under sensorimotor perturbations. Results indicate two different modes of distribution, one in which inner controls necessarily depend on a set of specific environmental factors to exhibit behaviour, then these controls will be more vulnerable to perturbations on that set, and another for which these factors are equally sufficient for behaviours. Vulnerability to perturbations depends on the particular distribution. In contrast to most existing approaches to the study of robustness, this thesis argues that behavioural robustness is better understood in the context of agent-environment dynamical couplings, not in terms of internal mechanisms. Such couplings, however, are not always the full determinants of robustness. Challenges and limitations of our approach are also identified for future studies.

Oscillatory neural activity is closely related to cognition and behaviour, with synchronisation mechanisms playing a key role in the integration and functional organization of different cortical areas. Nevertheless, its informational content and relationship with behaviour - and hence cognition - are still to be fully understood. This thesis is concerned with better understanding the role of neuronal oscillations and information dynamics towards the generation of embodied cognitive behaviours and with investigating the efficacy of such systems as practical robot controllers. To this end, we develop a novel model based on the Kuramoto model of coupled phase oscillators and perform three minimally cognitive evolutionary robotics experiments. The analyses focus both on a behavioural level description, investigating the robot's trajectories, and on a mechanism level description, exploring the variables' dynamics and the information transfer properties within and between the agent's body and the environment. The first experiment demonstrates that in an active categorical perception task under normal and inverted vision, networks with a definite, but not too strong, propensity for synchronisation are more able to reconfigure, to organise themselves functionally, and to adapt to different behavioural conditions. The second experiment relates assembly constitution and phase reorganisation dynamics to performance in supervised and unsupervised learning tasks. We demonstrate that assembly dynamics facilitate the evolutionary process, can account for varying degrees of stimuli modulation of the sensorimotor interactions, and can contribute to solving different tasks leaving aside other plasticity mechanisms. The third experiment explores an associative learning task considering a more realistic connectivity pattern between neurons. We demonstrate that networks with travelling waves as a default solution perform poorly compared to networks that are normally synchronised in the absence of stimuli. Overall, this thesis shows that neural synchronisation dynamics, when suitably flexible and reconfigurable, produce an asymmetric flow of information and can generate minimally cognitive embodied behaviours.

In this thesis, novel implementation methods for FPGA based real-time motion control systems are investigated. These methods are examined for conventional and modern controller topologies as well as peripheral device interfaces which are mutually essential pieces of a motion controller. The developed methods are initially tested one by one to assess the performance of the individual design / and finally an assembled solution is developed to test the overall design. Tests of the overall design are realized via hardware-in-the-loop simulation of a real-world control problem, selected as a CNC machining center. The developed methods are discussed in terms of their success, resource consumptions and attainable sampling rates.

This thesis describes the critical game flow and dynamic role assignment based on potential fields in robot soccer game and actions taken depending on role assignment. Role assignment is a standard problem of multi-agent game system like robot soccer and it can be realized by many techniques. In this thesis, game flow is described dynamically in terms of critical zones which is formed by potential fields based on the field environment as hills and valleys.

Orientador: Jose Ricardo Figueiredo / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica / Made available in DSpace on 2018-08-04T09:31:53Z (GMT). No. of bitstreams: 1 QuinterosPanesi_AndreRicardo_M.pdf: 5200860 bytes, checksum: 50a776e6a73c01814b4bfb64919bb6d7 (MD5) Previous issue date: 2005 / Resumo: Foi projetada e construída uma bomba de diafragma para um sistema de refrigeração por absorção de água-amônia que opera empregando vapor expandido entre os mesmos níveis de pressão de bombeamento. Através de uma bancada experimental, verificaram-se as condições de funcionamento da bomba que simula um sistema de absorção nas fases de sucção e recalque da solução água-amônia do absorvedor para o gerador através de um nível de baixa pressão para um nível de alta pressão. No teste utilizou-se um recipiente contendo água sujeito a baixa pressão no reservatório representando o absorvedor, um cilindro hermético a alta pressão com entradas e saídas necessárias para a tomada de ar e água representando o gerador, um compressor de ar para pressurização do sistema e dispositivos de controle e comando para a automação do sistema. Foi demonstrada a viabilidade de operação do equipamento como também as limitações encontradas do protótipo / Abstract: Was projected and constructed one diaphragm pump for one system of refrigeration for water-ammonia absorption that operates using expanded vapor it enters the same levels of pump action pressure. Through an experimental group of benches, the conditions of functioning of the pump had been verified that simulates a system of absorption in the suction phases and stresses of the solution water-ammonia of the absorber for the generator through an leveI of low pressure for an high-pressure leveI. In the test one container was used contains water subject to lowers pressure in the reservoir representing the absorber, an air-tight cylinder the high pressure with entrances and necessary exits for the water and air scoop representing the generator, an air compressor for pressurization of the system and devices of control and command for the a automation of the system. The viability of operation of the equipment was demonstrated as also the joined limitations of the archetype / Mestrado / Termica e Fluidos / Mestre em Engenharia Mecânica

Conceptual design synthesis is part of the conceptual phase of the design process, which focuses on creating alternative, candidate solutions. Conceptual design phase has the greatest influence on the cost and characteristics of the final product; an excellent detailed design based on a poor and inappropriate concept can never compensate for the inadequacy of the concept. Conceptual design is difficult, which currently relies on the designer’s intuition and experience to guide the process. A major issue in conceptual design is that often not many alternative candidate solutions are explored by the designer during the design process. The major reasons for this are the tendency to delimit a design problem area too narrowly and thus not being able to diversify the possible set of design solutions, possible bias towards a limited set of ideas, and time constraints. Many researchers recommended a thorough search of the design space for developing a good solution; this requires generation of a large solution space. Mechanical devices (mechanisms and machines) have fascinated the mankind throughout recorded history. Conceptual design synthesis of mechanical devices is difficult even for humans, and is also difficult to completely automate. In a single state design task, the relation between an input and output are fixed, but in a multiple state design task, the relation is not fixed. Much of the current research has been focused on supporting synthesis of single state devices, in particular where the device has to convert an input motion into an output motion. Synthesis of multiple state device is in contrast rather poorly understood and supported. Complete automation is unlikely to be possible; developing support taking into account the strength of computer and and human is important mechanical device is not adequate the biggest source for understanding of this process, and for its subsequent support, is human designers. The concept of state for a mechanical device is explained in detail by analyzing the existing multiple state mechanical devices. An operating state described by elemental functions (defined by efforts- motions of input and output components) and their associated Understanding and Supporting Conceptual Design Synthesis of Multiple State Mechanical Devices configurations and configuration changes. However, study of current literature indicates that little has been known about the actual processes carried out by designers in synthesizing multiple state devices. The main objectives of this thesis, therefore, are as follows: (1) understand the multiple state device design synthesis process carried out by designers, and (2) develop methods for supporting synthesis of multiple state mechanical devices to enhance the number of solution alternatives generated. Empirical studies are conducted to understand how designers currently carry out multiple state design tasks. Ten designers are given a multiple state design task and asked to generate as many solutions as possible. The designers are asked to think aloud while carrying out their synthesis processes. All these synthesis processes are video recorded, and analyzed to identify what activities are involved in the multiple state design synthesis, what the inputs are to each activity, and what the outcomes are from each activity. It has been found from these studies that design fixation is quite common, and the majority of the designers pursued developing a single solution to the given design task. A generic descriptive model of the multiple state mechanical device design synthesis process, explaining how this is carried by the designers, is developed. Based on this model, a prescriptive model of multiple state design synthesis process, explaining how the multiple state synthesis process should be carried by designers in order to develop a large solution space, is also developed. The prescriptive support, for synthesizing a large solution space for a given multiple state design task, has been evaluated. Eight engineering designers participated in the evaluation procedure, where each designer had to synthesize solutions for two, given multiple state design tasks. Results indicate that use of the prescriptive support, even without the power of a computational implementation, may have been beneficial in helping designers develop feasible solutions in a greater number of cases in a more efficient manner (that is, by considering fewer solution proposals and in similar amounts of time). All the designers who participated in this exercise gave a positive feedback regarding the prescriptive support. However, in none of the design sessions did the designers develop more than one feasible solution. This, along with various other comments from designers, indicates that a faster and more proactive support – implemented on computer – might be more useful in supporting the tasks. The various aspects for a potential computer support are discussed.

It is a great advantage of gaining knowledge about the environment for navigation. The environment should be measured during the employment as exactly as possible, in order to be able to react correctly. Robots are being used for different tasks at contaminated environments, places in danger or completely safe places. For robotic use, scanning capabilities of the environment are limited at the present. Adhering to the limitations of the scanning systems, the environment is scanned at a particular level and charted with appropriate software. In some cases, this scanning capability is not enough to react correctly. Taking these needs into consideration, this thesis successfully demonstrates the design and implementation of a scanning platform for mobile robotics. A scanning platform with a laser rangefinder scanner will be addressed in a compact design with maximum field of view for quickly mapping and high resolution. With this design, the scanning system will be provided by rotating laser rangefinder at z-axis in one dimension. Laser rangefinder will also measure the distance as the second dimension of the system. Also it rotates the laser beam at another axis which is different from the measuring distance axis and rotary z-axis. In this way, the scanning system will have the three-dimensional scanning ability. This design allows the scanning platform, continuous scanning capability at three dimensional.

In this thesis, the dynamic performances of kinematically and dynamically adjustable planar mechanisms have been investigated. An adjustable mechanism is here defined to be a mechanism where some of the kinematic and/or dynamic parameters are changed in a controlled manner in order to optimize the dynamic behaviour of the mechanism in spite of variable operating conditions. Here, variable operating conditions refer to variable load(s) on the mechanism and/or variable desired input motion. The dynamic behaviour of the mechanism may be optimized via minimization of the actuator torque/force fluctuations, minimization of energy consumed by the actuators etc. According to the type of the adjustable parameter, the adjustable mechanisms are classified into two groups namely, dynamically adjustable mechanisms and kinematically adjustable mechanisms. Mechanisms, where the main concern is to change a dynamic parameter(s) are called dynamically adjustable mechanisms. In the kinematically adjustable mechanisms, on the other hand , the main concern is to change a kinematic parameter(s). The main objective of this study is to investigate the benefits of adjustable planar mechanisms, regarding different dynamic behaviours under variable operating conditions. To achieve this objective , various simulations have been performed on the computer. In these simulations, practical constraints that will exist in a real application have been taken into account as much as possible. The results reveal that, in many cases, the dynamic behaviour of a planar mechanism may be improved quite extensively via adjustable mechanisms which are obtained from the original mechanisms with slight modifications.

In this study, it is aimed to improve the previously developed data acquisition program which was run under DOS and 2D surface reconstruction program under Windows. A new system is set up and both data acquisition and processing software are developed to collect and process data within just one application, running under Windows. The main goal of the thesis is to acquire and process the range data taken from the laser rangefinder in order to construct the 3D image map of simple objects in different positions for indoor environments. The data acquisition program collects data in helical way. To do this, appropriate parameters for the data acquisition interface are determined. In the data processing step, it is aimed to use basic triangulation algorithms and threshold conditions to calculate resolutions, detect noisy points and segment objects from the environment for line fitting. The developed and implemented data acquisition and processing interfaces in the thesis are capable of creating 3D image map and obtaining the view of scanned environment in a short time with high accuracy.

This thesis analyses the existing types of polyhedral linkages and presents new linkage types for resizing polyhedral shapes. First, the transformation characteristics, most specifically, magnification performances of existing polyhedral linkages are given. Then, methods for synthesizing single degree-of-freedom planar polygonal linkages are described. The polygonal linkages synthesized are used as faces of polyhedral linkages. Next, the derivation of some of the existing linkages using the method given is presented. Finally, some designs of cover panels for the linkages are given. The Cardan Motion is the key point in both analyses of existing linkages and synthesis of new linkages.