The motivation that originated this work was the desire to create an invasion team sports simulator capable of applying user defined strategies to guide the behavior of the agents in the simulation. With this objective in mind we created a formal strategy model to describe complex team behavior and developed methods of using that model to calculate collective plans. We defined both the strategy model and the planning methods in a broad manner that can be applied in many different domains. Then we defined a basketball simulation domain and implemented our methodology to develop a simulator. We also present a control system architecture that is compatible with our proposed planner and show how we implemented it to create the basketball simulator. The formal strategy model we developed can be used to represent team behavior, analyze real world events and create simulations. We developed a strategy design tool that allows the end user to create and visualize team strategies for basketball. Finally, we developed a system that interprets the user generated strategies and creates a basketball match simulation of the described behavior. We also proposed a methodology for the development of simulation systems involving multiple intelligent agents. Our recommended control system architecture separates the many layers of control, which simplifies the development process and results in a naturally expansible system. In this thesis we have provided a novel approach to collective behavior simulation utilizing user input as a guide to the strategy planning. Both the theory and methods developed have been tested through the implementation of a basketball simulator and the results were satisfactory. We believe this is a seminal work that will lead to many interesting developments, both in the realm of sports and in broader domains. / A motivação que deu origem a esse trabalho foi um desejo de criarmos um simulador de esportes de invasão coletivos capaz de aplicar estratégias definidas pelo usuário para guiar o comportamento de agentes na simulação. Com esse objetivo em mente nós criamos um modelo formal de estratégia para descrever comportamentos complexos em equipe e desenvolvemos métodos para usar esse modelo no cálculo de planos coletivos. Definimos o modelo e os métodos de planejamento de uma forma abrangente que pode ser aplicada em muitos domínios diferentes. Definimos um domínio para a simulação de partidas de basquete e implementamos nossa metodologia para desenvolver um simulador. Também apresentamos uma arquitetura de controle que é compatível com o planejador proposto e mostramos como implementá-la na criação de um simulador de basquete. O modelo formal que desenvolvemos pode ser usado para representar comportamento coletivo, analisar eventos reais e criar simulações. Desenvolvemos um desenhador de estratégia que permite que o usuário final desenhe e visualize estratégias de equipes de basquete. Finalmente, desenvolvemos um sistema que interpreta o conteúdo gerado pelo usuário e cria uma simulação de basquete usando o comportamento descrito. Propusemos também uma metodologia para o desenvolvimento de sistemas de simulação envolvendo múltiplos agentes inteligentes. Nossa arquitetura de controle separa as várias camadas de controle, simplificando o processo de desenvolvimento e resultando em um sistema naturalmente expansível.

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A map is a description of an environment allowing an agent--a human, or in our case a mobile robot--to plan and perform effective actions. From a single location, an agent’s sensors can not observe the whole structure of a complex, large environment. For this reason, the agent must build a map from observations gathered over time and space. We distinguish between large-scale space, with spatial structure larger than the agent’s sensory horizon, and small-scale space, with structure within the sensory horizon. We propose a factored approach to mobile robot map-building that handles qualitatively different types of uncertainty by combining the strengths of topological and metrical approaches. Our framework is based on a computational model of the human cognitive map; thus it allows robust navigation and communication within several different spatial ontologies. Our approach factors the mapping problem into natural sub-goals: building a metrical representation for local small-scale spaces; finding a topological map that represents the qualitative structure of large-scale space; and (when necessary) constructing a metrical representation for large-scale space using the skeleton provided by the topological map. The core contributions of this thesis are a formal description of the Hybrid Spatial Semantic Hierarchy (HSSH), a framework for both small-scale and large-scale representations of space, and an implementation of the HSSH that allows a robot to ground the largescale concepts of place and path in a metrical model of the local surround. Given metrical models of the robot’s local surround, we argue that places at decision points in the world can be grounded by the use of a primitive called a gateway. Gateways separate different regions in space and have a natural description at intersections and in doorways. We provide an algorithmic definition of gateways, a theory of how they contribute to the description of paths and places, and practical uses of gateways in spatial mapping and learning. / text

The motivation that originated this work was the desire to create an invasion team sports simulator capable of applying user defined strategies to guide the behavior of the agents in the simulation. With this objective in mind we created a formal strategy model to describe complex team behavior and developed methods of using that model to calculate collective plans. We defined both the strategy model and the planning methods in a broad manner that can be applied in many different domains. Then we defined a basketball simulation domain and implemented our methodology to develop a simulator. We also present a control system architecture that is compatible with our proposed planner and show how we implemented it to create the basketball simulator. The formal strategy model we developed can be used to represent team behavior, analyze real world events and create simulations. We developed a strategy design tool that allows the end user to create and visualize team strategies for basketball. Finally, we developed a system that interprets the user generated strategies and creates a basketball match simulation of the described behavior. We also proposed a methodology for the development of simulation systems involving multiple intelligent agents. Our recommended control system architecture separates the many layers of control, which simplifies the development process and results in a naturally expansible system. In this thesis we have provided a novel approach to collective behavior simulation utilizing user input as a guide to the strategy planning. Both the theory and methods developed have been tested through the implementation of a basketball simulator and the results were satisfactory. We believe this is a seminal work that will lead to many interesting developments, both in the realm of sports and in broader domains. / A motivação que deu origem a esse trabalho foi um desejo de criarmos um simulador de esportes de invasão coletivos capaz de aplicar estratégias definidas pelo usuário para guiar o comportamento de agentes na simulação. Com esse objetivo em mente nós criamos um modelo formal de estratégia para descrever comportamentos complexos em equipe e desenvolvemos métodos para usar esse modelo no cálculo de planos coletivos. Definimos o modelo e os métodos de planejamento de uma forma abrangente que pode ser aplicada em muitos domínios diferentes. Definimos um domínio para a simulação de partidas de basquete e implementamos nossa metodologia para desenvolver um simulador. Também apresentamos uma arquitetura de controle que é compatível com o planejador proposto e mostramos como implementá-la na criação de um simulador de basquete. O modelo formal que desenvolvemos pode ser usado para representar comportamento coletivo, analisar eventos reais e criar simulações. Desenvolvemos um desenhador de estratégia que permite que o usuário final desenhe e visualize estratégias de equipes de basquete. Finalmente, desenvolvemos um sistema que interpreta o conteúdo gerado pelo usuário e cria uma simulação de basquete usando o comportamento descrito. Propusemos também uma metodologia para o desenvolvimento de sistemas de simulação envolvendo múltiplos agentes inteligentes. Nossa arquitetura de controle separa as várias camadas de controle, simplificando o processo de desenvolvimento e resultando em um sistema naturalmente expansível.

When interpreting how an animal "learns" discrimination tasks, strain capabilities must be considered, and it should be shown that they comprehend the task in a manner consistent with the given interpretation. A novel visual-discrimination (VD) task for relative-size-relations was used to examine visual cue use in C57BL/6J mice, which are shown to have biologically good vision and neurologically intact memory for VD tasks. Results suggest C57BL/6J strain may not be fully capable of relative cue-size associations or even object recognition-based on a water maze VD task. This is in contrast to previous studies suggesting this mice strain is quite strong in visual skills and on VD tasks. Additionally, cue size and/or cue-pairings do appear to influence specific directional preferences or stereotyped behaviors as trainings continued, and these strategies shifted during novel probes. Future studies should assess how mice discriminate between objects and test rat's capabilities on this task. / by Eric D. Buerger. / Thesis (M.A.)--Florida Atlantic University, 2008. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2008. Mode of access: World Wide Web.

In the simulation of human crowd behavior including evacuation planning, transportation management, and safety engineering in architecture design, the development of pedestrian model for higher behavior fidelity is an important task. To construct plausible facsimiles of real crowd movements, simulations should exhibit human behaviors for navigation, pedestrian decision-making, and social behaviors such as grouping and crowding. The research field is quite mature in some sense, with a large number of approaches that have been proposed to path finding, collision avoidance, and visually pleasing steering behaviors of virtual humans. However, there is still a clear disparity between the variety of approaches and the quality of crowd behaviors in simulations. Many social science field studies inform us that crowds are typically composed of multiple social groups (James, 1953; Coleman and James, 1961; Aveni, 1977). These observations indicate that one component of the complexity of crowd dynamics emerges from the presence of various patterns of social interactions within small groups that make up the crowd. Hence, realism in a crowd simulation may be enhanced when virtual characters are organized in multiple social groups, and exhibit human-like coordination behaviors. Motivated by the need for modeling groups in a crowd, we present a multi-agent model for large crowd simulations that incorporates socially plausible group behaviors. A computational model for multi-agent coordination and interaction informed by well- established Common Ground theory (Clark, 1996; Clark and Brennan, 1991) is proposed. In our approach, the task of navigation in a group is viewed as performing a joint activity which requires maintaining a state of common ground among group members regarding walking strategies and route choices. That is, group members communicate with, and adapt their behaviors to each other in order to maintain group cohesiveness while walking. In the course of interaction, an agent may present gestures or other behavioral cues according to its communicative purpose. It also considers the spatiotemporal conditions of the agent-group's environment in which the agent interacts when selecting a kind of motions. With the incorporation of our agent model, we provide a unified framework for crowd simulation and animation which accommodates high-level socially-aware behavioral realism of animated characters. The communicative purpose and motion selection of agents are consistently carried through from simulation to animation, and a resulted sequence of animated character behaviors forms not merely a chain of reactive or random gestures but a socially meaningful interactions. We conducted several experiments in order to investigate the impact of our social group interaction model in crowd simulation and animation. By showing that group communicative behaviors have a substantial influence on the overall distribution of a crowd, we demonstrate the importance of incorporating a model of social group interaction into multi-agent simulations of large crowd behaviors. With a series of perceptual user studies, we show that our model produces more believable behaviors of animated characters from the viewpoint of human observers. / Ph. D.

Orientador: Siome Klein Goldenstein / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Computação / Made available in DSpace on 2018-08-16T21:25:11Z (GMT). No. of bitstreams: 1 Saboia_PriscilaCorrea_M.pdf: 2582894 bytes, checksum: 1645aa6b8b779ee7180adbbb04d23981 (MD5) Previous issue date: 2010 / Resumo: Atualmente, estima-se que a população mundial seja de cerca de seis bilhões e oitocentos milhões de habitantes (6.800.000.000), dos quais metade mora em aglomerados urbanos. Nestes centros, é corriqueiro o fen¿omeno da movimentação de multidões. Tecnicamente, entende-se multidão como um grande grupo de indivíduos em um mesmo ambiente físico, compartilhando um objetivo comum e podendo agir diferentemente do que quando estão sozinhos. Compreender a movimentação destas multidões é de vital import¿ancia para o planejamento e a melhoria dos locais públicos, não só no sentido de facilitar e agilizar o deslocamento dos cidadãos, mas também garantir-lhes segurança, especialmente em condições de perigo iminente, onde pode haver a necessidade de evacuação de tais locais. Além disso, existem várias áreas do conhecimento que têm potencial para se beneficiar do estudo do comportamento de multidões. Na indústria de entretenimento, por exemplo, simulações de multidões podem ser utilizadas na produção de animações e jogos de computador. No treinamento policial e militar, simulações podem ser usadas para demonstração e controle de rebeliões. Na área de engenharia de segurança, simulações podem ser utilizadas para estudo de desocupação emergencial de construções, navios e aviões. Em todas as áreas citadas, observa-se que a necessidade por simulações de multidões advém de duas situações que podem ocorrer no mundo real. Primeiramente, pode ser perigoso para os indivíduos realizar as ações objetivadas (como cair de um prédio em um filme, ou evacuar uma sala de cinema em chamas, por exemplo), bem como é antiético submetê-los a tais condições. Segundo, é muito complexo e oneroso lidar com um grande número de indivíduos no mundo real. Ambas as situações podem ser evitadas pela simulação computacional da situação real. Nestes termos, o objetivo desta dissertação é modelar a movimentação de multidões, tendo em vista a simulação em computador. Para tanto, sistemas multiagentes brownianos são introduzidos como uma alternativa tecnológica 'a implementação dos modelos encontrados na literatura, bem como 'a implementação de um novo modelo de movimentação de multidões, híbrido por reunir conceitos de modelos que lançam mão das chamadas forças sociais, com conceitos de modelos baseados na estratégia Lattice-Gas. Como resultado prático, um novo simulador de sistemas multiagentes construído para a tarefa de simulação de movimentação de multidões é apresentado / Abstract: Currently, it is estimated that world population is about six billion and eight hundred million inhabitants (6.8 billion), of whom half live in urban areas. In these centers, it is common the phenomenon of moving crowds. Technically, a crowd can be seen as a large group of individuals put in the same physical environment, sharing a common goal and acting differently than when they are alone. Understanding the movement of these crowds is very important for planning and improving public places, not only in order to facilitate and expedite the movement of citizens, but also in order to guarantee their safety, especially in conditions of imminent danger, where it can be necessary the evacuation of such sites. Furthermore, there are several areas of knowledge that can gain benefits from the study of crowd behavior. In the entertainment industry, for example, crowd simulations can be used to produce animations and computer games. In Police and military training, simulations can be used for demonstration and control of riots. In the area of safety engineering, simulations can be used to study the urgent evacuation of buildings, ships and aircrafts. In all mentioned areas, it is observed that the need for crowd simulations comes from two situations, taking into consideration the real world. First, it can be dangerous for individuals to perform the desired actions (like falling from a building in a movie, or evacuating the room on fire of a failing movie session). It is also unethical to expose them to such conditions. Second, it is very complex and expensive to handle a large number of individuals in the real world. Both situations can be dealt by simulating the real world into a computer. Thus, this dissertation aims to model the movement of crowds, always having in mind the computer simulation. For this, Brownian multi-agent systems are introduced as a technological alternative to implement the models found in literature, as well as to implement a new hybrid movement model, that gathers together concepts from solutions based on social forces, and solutions based on Lattice- Gas. As a practical result, a new simulator for multi-agent systems is presented, built for the task of simulating moving crowds / Mestrado / Sistemas de Informação / Mestre em Ciência da Computação

Orientadores: Leo Pini Magalhães, Soraia Raupp Musse / Acompanha 1 CD-ROM / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação / Made available in DSpace on 2018-08-14T12:44:21Z (GMT). No. of bitstreams: 1 Bicho_AlessandrodeLima_D.pdf: 3153035 bytes, checksum: 02699fbfe11ede429a8d387c957cfb0d (MD5) Previous issue date: 2009 / Resumo: Este trabalho apresenta um método para simulação de multidões baseado no algoritmo de colonização do espaço. Este algoritmo foi originalmente proposto para modelar padrões de nervuras em folhas vegetais e de ramificações em árvores. A técnica baseia-se na competição por espaço entre nervuras ou ramificações durante o crescimento vegetal. Adaptado à simulação de multidões, o algoritmo de colonização do espaço visa simular a competição por espaço durante o movimento dos pedestres. Vários comportamentos observados em multidões reais, tais como evitar colisões, variar a velocidade de deslocamento do pedestre em função da densidade populacional e formar vias (lanes) de pedestres, nas quais o pedestre seguirá aquele imediatamente a sua frente, cuja direção e sentido são similares, são propriedades do algoritmo. O modelo de simulação de multidões proposto também caracteriza-se pela simplicidade de implementação, robustez e eficência computacional, permitindo, de acordo com o ambiente de simulação adotado, o controle interativo da multidão simulada. / Abstract: This work presents a method for crowd simulation based on the biologically-motivated space colonization algorithm. This algorithm was originally introduced to model leaf venation patterns and the branching architecture of trees. It operates by simulating the competition for space between growing veins or branches. Adapted to crowd modeling, the space colonization algorithm focuses on the competition for space among moving agents. Several behaviors observed in real crowds, including collision avoidance, relationship of crowd density and speed of agents, and the formation of lanes in which people follow each other, are properties of the algorithm. The proposed crowd modeling method is simple to implement, robust, computationally efficient, and suited to the interactive control of simulated crowds. / Doutorado / Engenharia de Computação / Doutor em Engenharia Elétrica

The traditional pen-paper sketching is extensively used in the early stages of product design as it supports creative exploration of product concepts and provides a fluidic mode for the expression of ideas. The Computer Aided Design (CAD) models support the later stages of design and manufacturing process. Faithful conversion of the designer’s ideas from concept sketches to the CAD models is a skill intensive and time consuming exercise which reduces the overall productivity of the organization. Providing computer based support can help the designer, in several ways, by reducing demand on the skill and allow focusing more on creative exploration of the concepts. Towards that, the thesis presents methodologies to understand the product concept sketches, support cognitive activities like perceiving the composition and behaviour, and create and interact with the sketches, directly in 3D. To begin with, traditional 2D sketches of product concepts are studied mainly to explores the psychological (cognitive) and physiological (musculoskeletal) activities of the designer in the context of the product being designed. A sketching application is created for capturing the sketches created using a tablet in digitized form. The captured data is analyzed based on the identified parameters. A grouping methodology is devised to group the stroke based on the observations which are akin to Gestalt laws of perceptual organization. This functional grouping or segmentation is used to identify the mental model of the product concept and the design rationale behind it. In concept sketches, annotations carry information like behaviour, functionality and usage. These wishful declarations need to be verified through simulation! To simulate the behavior of the components identified by the functional segmentation method, a kinematic model is defined where the designers interactively describe the constituents like joints, fixed links, inputs, etc. The interactive simulation changes the underlying kinematic model and makes the sketches to move to show the behavior. This system also provides methods to verify boundary constraints and allows creating patterns. Traditional 2D sketching suffers from several deficiencies. To overcome these, a novel direct 3D sketching methodology is proposed with stereo vision and haptic feedback. Different types of strokes creations like curves, strips and sweep surfaces, directly in 3D space, are demonstrated. Further, to provide control over stroke creation process, visual and haptic feedbacks are studied. Haptic rendering schemes for stroke generation are explored based on mechanics of sketching. Using the curve generation methods, surface generation schemes are devised. Mainly two types of schemes are explored (a) sweep surface and (b) Hatching surfaces. To support constrained concept exploration, two types of haptic constraints are modeled and their application is demonstrated in constraining a sketch within a boundary and outside a boundary. Motion constraints are implemented by simulating the behaviour of identified components’ motions. Two types of motion are implemented (a) Linear translation and (b) Rotation about an axis. Finally, a sketch based distributed collaboration method is presented to enable design interaction in the context of global product development. Several issues related to the realization of a sketch based collaborative conceptual design system are explored and, one such instance is demonstrated through experiments.

The focus of the present work is natural human like grasping, for realistic performance simulations in digital human modelling (DHM) environment. The performance simulation for grasping in DHM is typically done through high level commands to the digital human models (DHMs). This calls for a natural and unambiguous scheme to describe a grasp which would implicitly accommodate variations due to the hand form, object form and hand kinematics. A novel relational description scheme is developed towards this purpose. The grasp is modelled as a spatio-temporal relationship between the patches (a closed region on the surface) in the hand and the object. The task dependency of the grasp affects only the choice of the relevant patches. Thus, the present scheme of grasp description enables a human like grasp description possible. Grasping can be simulated either in an interactive command mode as discussed above or in an autonomous mode. In the autonomous mode the patches have to be computed. It is done using a psychological concept, of affordance. This scheme is employed to select a tool from a set of tools. Various types of grasps a user may adopt while grasping a spanner for manipulating a nut is simulated. Grasping of objects by human evolves through distinct naturally occurring phases, such as re-oreintation, transport and preshape. Hand is taken to the object ballpark using a novel concept of virtual object. Before contact establishment hand achieves the shape similar to the global shape of the object, called preshaping. Various hand preshape strategies are simulating using an optimization scheme. Since the focus of the present work is human like grasping, the mechanism which drives the DHMs should also be anatomically pertinent. A methodology is developed wherein the hand-object contact establishment is done based on the anatomical observation of logarithmic spiral pattern during finger flexion. The effect of slip in presence of friction has been studied for 2D and 3D object grasping endeavours and a computational generation of the slip locus is done. The in-grasp slip studies are also done which simulates the finger and object response to slip. It is desirable that the grasping performance simulations be validated for diverse hands that people have. In the absence of an available database of articulated bio-fidelic digital hands, this work develops a semi-automatic methodology for developing subject specific hand models from a single pose 3D laser scan of the subject's hand. The methodology is based on the clinical evidence that creases and joint locations on human hand are strongly correlated. The hand scan is segmented into palm, wrist and phalanges, both manually and computationally. The computational segmentation is based on the crease markings in the hand scan, which is identified by explicitly painting them using a mesh processing software by the user. Joint locations are computed on this segmented hand. A 24 dof kinematic structure is automatically embedded into the hand scan. The joint axes are computed using a novel palm plane normal concept. The computed joint axes are rectified using the convergence, and intra-finger constraints. The methodology is significantly tolerant to the noise in the scan and the pose of the hand. With the proposed methodology articulated, realistic, custom hand models can be generated. Thus, the reported work presents a geometric framework for comprehensive simulation of grasping performance in a DHM environment.