Agent Behaviour Simulator (ABS):a platform for urban behaviour development

Computer Graphics have become important for many applicationsand the quality of the produced images have greatly improved. Oneof the interesting remaining problems is the representation of densedynamic environments such as populated cities. Although recentlywe saw some successfulwork on the rendering such environments,the real?time simulation of virtual cities populated by thousands ofintelligent animated agents is still very challenging.In this paperwe describe a platformthat aims to accelerate the developmentof agent behaviours. The platform makes it easy to enterlocal rules and callbacks which govern the individual behaviours.It automatically performs the routine tasks such as collision detectionallowing the user to concentrate on defining the more involvedtasks. The platform is based on a 2D-grid with a four-layered structure.The two first layers are used to compute the collision detectionagainst the environment and other agents and the last two are usedfor more complex behaviours.A set of visualisation tools is incorporated that allows the testingof the real?time simulation. The choices made for the visualisationallow the user to better understand the way agents move inside theworld and how they take decisions, so that the user can evaluate ifit simulates the expected behaviour.Experimentation with the system has shown that behaviours inenvironments with thousands of agents can be developed and visualisedin effortlessly

GIS Data Based Automatic High-Fidelity 3D Road Network Modeling

3D road models are widely used in many computer applications such as racing games and driving simulations_ However, almost all high-fidelity 3D road models were generated manually by professional artists at the expense of intensive labor. There are very few existing methods for automatically generating 3D high-fidelity road networks, especially those existing in the real world. This paper presents a novel approach thai can automatically produce 3D high-fidelity road network models from real 2D road GIS data that mainly contain road. centerline in formation. The proposed method first builds parametric representations of the road centerlines through segmentation and fitting . A basic set of civil engineering rules (e.g., cross slope, superelevation, grade) for road design are then selected in order to generate realistic road surfaces in compliance with these rules. While the proposed method applies to any types of roads, this paper mainly addresses automatic generation of complex traffic interchanges and intersections which are the most sophisticated elements in the road network

An algorithmic definition of the axial map

The fewest-line axial map, often simply referred to as the 'axial map, is one of the primary tools of space syntax. Its natural language definition has allowed researchers to draw consistent maps that present a concise description of architectural space; it has been established that graph measures obtained from the map are useful for the analysis of pedestrian movement patterns and activities related to such movement: for example, the location of services or of crime. However, the definition has proved difficult to translate into formal language by mathematicians and algorithmic implementers alike. This has meant that space syntax has been criticised for a lack of rigour in the definition of one of its fundamental representations. Here we clarify the original definition of the fewest-line axial map and show that it can be implemented algorithmically. We show that the original definition leads to maps similar to those currently drawn by hand, and we demonstrate that the differences between the two may be accounted for in terms of the detail of the algorithm used. We propose that the analytical power of the axial map in empirical studies derives from the efficient representation of key properties of the spatial configuration that it captures

Encoding natural movement as an agent-based system: an investigation into human pedestrian behaviour in the built environment

Gibson's ecological theory of perception has received considerable attention within psychology literature, as well as in computer vision and robotics. However, few have applied Gibson's approach to agent-based models of human movement, because the ecological theory requires that individuals have a vision-based mental model of the world, and for large numbers of agents this becomes extremely expensive computationally. Thus, within current pedestrian models, path evaluation is based on calibration from observed data or on sophisticated but deterministic route-choice mechanisms; there is little open-ended behavioural modelling of human-movement patterns. One solution which allows individuals rapid concurrent access to the visual information within an environment is an 'exosomatic visual architecture" where the connections between mutually visible locations within a configuration are prestored in a lookup table. Here we demonstrate that, with the aid of an exosomatic visual architecture, it is possible to develop behavioural models in which movement rules originating from Gibson's principle of affordance are utilised. We apply large numbers of agents programmed with these rules to a built-environment example and show that, by varying parameters such as destination selection, field of view, and steps taken between decision points, it is possible to generate aggregate movement levels very similar to those found in an actual building context

Analysing the visual dynamics of spatial morphology

Recently there has been a revival of interest in visibility analysis of architectural configurations. The new analyses rely heavily on computing power and statistical analysis, two factors which, according to the postpositivist school of geography, should immediately cause us to be wary. Thedanger, they would suggest, is in the application of a reductionist formal mathematical description in order to `explain' multilayered sociospatial phenomena. The author presents an attempt to rationalise how we can use visibility analysis to explore architecture in this multilayered context by considering the dynamics that lead to the visual experience. In particular, it is recommended that we assess the visualprocess of inhabitation, rather than assess the visibility in vacuo. In order to investigate the possibilities and limitations of the methodology, an urban environment is analysed by means of an agent-based model of visual actors within the configuration. The results obtained from the model are compared with actual pedestrian movement and other analytic measurements of the area: the agents correlate well both with human movement patterns and with configurational relationship as analysed by space-syntax methods. The application of both methods in combination improves on the correlation with observed movement of either, which in turn implies that an understanding of both the process of inhabitation and the principles of configuration may play a crucial role in determining the social usage of space

Space and Time Constrained Task Scheduling for Crowd Simulation

Crowd simulation, through the generation of realistic pedestrian ows and densities, has a great potential as a validation tool for urban planning or design of public buildings. In macroscopic simulations approaches, agents are modelled such as their behaviour mimics human's one in similar situations. As a consequence, realistic macroscopic phenomena are expected to emerge from the sum of all agents decisions. When performing an intended activity, people decisions and behaviour mainly consist in scheduling tasks that compose this activity, planning paths between locations where these tasks should be performed, navigating along the planned paths and performing the scheduled tasks. In this paper, we focus on the task scheduling process. This task scheduling process aims at selecting where, when and in which order several tasks, representing the intended activity, should be performed. The proposed model handles spatial and temporal constraints relating to the environment and to the agent itself. Personal preferences, characterizing the agent, are also taken into account. Produced task schedules are optimized on the long term and exhibit adequate choices of locations and times with respect to the agent intended activity and its environment. We conducted an experiment that shows that our algorithm produces task schedules which are representative of human's ones. Once computed, these task schedules are relaxed and used to drive a microscopic crowd simulation in which observable ows of pedestrians emerge from the scheduled individual activities. Such simulations are easy to produce and do not require the use of a complex decisional model.La simulation de foule, à travers la génération de flux et de densités de piétons réalistes, possède un grand potentiel en tant qu'outil de validation d'aménagements urbains. Les approches microscopiques visent à modéliser des agents virtuels dont le comportement imite celui d'humains se trouvant dans des situations similaires. En conséquence, l'apparition de phénomènes macroscopiques doit résulter de la somme des décisions des agents. Les décisions et comportements des personnes effectuant une activité consistent principalement à ordonnancer les tâches qui constituent cette dernière, planifier des chemins entre les lieux où les tâches doivent être effectuées, naviguer le long de ces chemins et effectuer ces tâches. Dans cet article, nous nous focalisons sur le processus d'ordonnancement de tâches. Ce processus vise à sélectionner où, quand et dans quel ordre des tâches, représentant une activité désirée, doivent être effectuées. Le modèle proposé gère les contraintes temporelles et spatiales associées à l'environnement et à l'agent lui-même ainsi que les préférences personnelles qui caractérisent l'agent. Les ordonnancements de tâches calculés sont optimisés sur la durée et démontrent des choix de lieux et d'horaires en adéquation avec l'activité de l'agent et son environnement. Nous avons effectué une expérience qui a démontré que notre algorithme produit des ordonnancements de tâches représentatifs de ceux effectuées par des humains. Après une phase de relaxation des contraintes temporelles associées à l'ordonnancement, ce dernier est utilisé pour diriger un modèle microscopique de simulation de foule. Des flots et densités de piétons réalistes émergent des activités individuelles. Ces simulations sont aisées à produire et ne nécessitent pas d'utiliser de modèle décisionnel complexe, permettant ainsi de peupler rapidement et de manière réaliste des environnements complexes

Automatic High-Fidelity 3D Road Network Modeling

Many computer applications such as racing games and driving simulations frequently make use of 3D high-fidelity road network models for a variety of purposes. However, there are very few existing methods for automatic generation of 3D realistic road networks, especially for those in the real world. On the other hand, vast road network GIS data have been collected in the past and used by a wide range of applications, such as navigation and evaluation. A method that can automatically produce 3D high-fidelity road network models from 2D real road GIS data will significantly reduce both the labor and time needed to generate these models, and greatly benefit numerous applications involving road networks. Based on a set of selected civil engineering rules for road design, this dissertation research addresses this problem with a novel approach which transforms existing road GIS data that contain only 2D road centerline information into 3D road network models. The proposed method consists of several components, mainly including road GIS data preprocessing, 3D centerline modeling and 3D geometry modeling. During road data preprocessing, topology of the road network is extracted from raw road data as a graph composed of road nodes and road links; road link information is simplified and classified. In the 3D centerline modeling part, the missing height information of the road centerline is inferred based on 2D road GIS data, intersections are extracted from road nodes and the whole road network is represented as road intersections and road segments in parametric forms. Finally, the 3D road centerline models are converted into various 3D road geometry models consisting of triangles and textures in the 3D geometry modeling phase. With this approach, basic road elements such as road segments, road intersections and traffic interchanges are generated automatically to compose sophisticated road networks. Results show that this approach provides a rapid and efficient 3D road modeling method for applications that have stringent requirements on high-fidelity road models

Regeneração do Rio Alenquer: Complexo Desportivo da Romeira: Centro de Reabilitação e Treino de Alto Rendimento

A presente dissertação descreve a investigação desenvolvida no âmbito da componente teórica da disciplina de Projeto Final de Arquitetura (PFA). O trabalho de investigação desenvolveu-se sobre o campo tecnológico da simulação de multidões e defende uma metodologia que propõe a integração da simulação por agentes autónomos, facilitada pela interoperabilidade da metodologia BIMFM. O modelo 3D paramétrico do edifício em formato IFC, transportando informação semântica fulcral para a relação entre o indivíduo e o edifício/cenário é usado como base da simulação. O software de simulação utilizado permite uma análise visual, gráfica e analítica de variáveis, úteis da fase de projeto à gestão de património. Conforme o nível de maturidade do modelo BIM evolui, o modelo social de simulação, permite por processos simples, a atualização do cenário e evolução dos parâmetros sociais. Embora com algumas limitações, a simulação do desempenho sócio espacial acrescenta uma dimensão espaço-tempo, ausente de forma geral das ferramentas de sintaxe espacial atuais. Um modelo que suporte um padrão social de um contexto específico permite o estudo exaustivo de variáveis resultantes da relação ambiente-comportamento em multidão a diferentes níveis. O ensaio e desenvolvimento constante dos parâmetros sociais, a par do ambiente virtual, assentam na interpretação cognitiva de agentes programados por algoritmos de inteligência artificial. O caso de estudo visa um cenário específico, inserido num contexto de metodologia BIM-FM do campus universitário do ISCTE-IUL, onde a dimensão e complexidade social dos utilizadores do campus, tem um grande impacto diário no desempenho geral da organização.This dissertation describes the investigation developed in the theoric component of the Projeto Final de Arquitetura discipline. The investigation work was developed on the technologic field of crowds simulation and it defends a methodology that propose the integration of simulation of independent agents, facilitated by BIM_FM methodologies interoperability. The 3D parametric model of the build in IFC format, by transporting semantic information that is core to the relation between the individual and the building/scenario, is used as the base of simulation. The simulation software allows a visual, graphic and analytical review of the variables, that are useful from the project stage to the management. As the maturity of the BIM model grows, the social model of simulation allows, by simples processes, the scenario’s update and the evolution of social parameters. Thought some limitations, the simulation of social-spatial performance brings a space-time dimention, generally absent from today’s spatial syntax tools. A model that supports a social pattern of a specific context allows the exhaustive study of variables that result from the environment-behavior relationship in crown in several levels. The constant test and development of the social parameters, besides the virtual environment, are based on the cognitive interpretation of agents programmed by artificial intelligence algorithms. The study case aims a specific scenario that is inserted in a contexto of a BIM-FM methodology of the ISCTE-IUL university campus, where the dimension and social complexity of campus users have a big daily impact in the general organization’s performance