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

Ageing Futures: Towards Cognitively Inclusive Digital Media Products

This thesis is situated in a moment when the theory and practice of inclusive design appears to be significantly implicated in the social and economic response to demographic changes in Western Europe by addressing the need to reconnect older people with technology. In light of claims that cognitive ageing results in an increasing disconnection from novel digital media in old age, inclusive design is apparently trapped in a discourse in which digital media products and interfaces are designed as a response to a deterministic decline in abilities. The thesis proceeds from this context to ask what intellectual moves are required within the discourses of inclusive design so that its community of theorists and practitioners can both comprehend and afford the enaction of cognitive experience in old age? Whilst influential design scholarship actively disregards reductionist cognitive explanations of human and technological relationships, it appears that inclusive design still requires an explanation of temporal changes to human cognition in later life. Whilst there is a burgeoning area of design related research dealing with this issue—an area this thesis defines as ‘cognitively inclusive design’—the underlying assumptions and claims supporting this body of research suggests its theorists and practitioners are struggling to move beyond conceptualising older people as passive consumers suffering a deterioration in key cognitive abilities. The thesis argues that, by revisiting the cognitive sciences for alternative explanations for the basis of human cognition, it is possible to relieve this problem by opening up new spaces for designers to critically reflect upon the manner in which older people interact with digital media. In taking a position that design is required to support human cognitive enactment, the thesis develops a new approach to conceptualising temporal changes in human cognition, defined as ‘senescent cognition’. From this new critical lens, the thesis provides an alternative ‘senescentechnic’ explanation of cognitive disconnections between older people and digital media that eschews reductionism and moves beyond a deterministic process of deterioration. In reassessing what ageing cognition means, new strategies for the future of inclusive design are proposed that emphasise the role of creating space for older people to actively explore, reflect upon and enact their own cognitive couplings with technology.Arts and Humanities Research Counci

Ecological adaptation in the context of an actor-critic

Biological beings are the result of an evolutionary and developmental process of adaptation to the environment they perceive and where they act. Animals and plants have successfully adapted to a large variety of environments, which supports the ideal of inspiring artificial agents after biology and ethology. This idea has been already suggested by previous studies and is extended throughout this thesis. However, the role of perception in the process of adaptation and its integration in an agent capable of acting for survival is not clear.Robotic architectures in AI proposed throughout the last decade have broadly addressed the problems of behaviour selection, namely deciding "what to do next", and of learning as the two main adaptive processes. Behaviour selection has been commonly related to theories of motivation, and learning has been bound to theories of reinforcement. However, the formulation of a general theory including both processes as particular cases of the same phenomenon is still an incomplete task. This thesis focuses again on behaviour selection and learning; however it proposes to integrate both processes by stressing the ecological relationship between the agent and its environment. If the selection of behaviour is an expression of the agent's motivations, the feedback of the environment due to behaviour execution can be viewed as part of the same process, since it also influences the agent's internal motivations and the learning processes via reinforcement. I relate this to an argument supporting the existence of a common neural substrate to compute motivation and reward, and therefore relating the elicitation of a behaviour to the perception of reward resulting from its executionAs in previous studies, behaviour selection is viewed as a competition among parallel pathways to gain control over the agent's actuators. Unlike for the previous cases, the computation of every motivation in this thesis is not anymore the result of an additive or multiplicative formula combining inner and outer stimuli. Instead, the ecological principle is proposed to constrain the combination of stimuli in a novel fashion that leads to adaptive behavioural patterns. This method aims at overcoming the intrinsic limitations of any formula, the use of which results in behavioural responses restricted to a set of specific patterns, and therefore to the set of ethological cases they can justify. External stimuli and internal physiology in the model introduced in this thesis are not combined a priori. Instead, these are viewed from the perspective of the agent as modulatory elements biasing the selection of one behaviour over another guided by the reward provided by the environment, being the selection performed by an actor-critic reinforcement learning algorithm aiming at the maximum cumulative reward.In this context, the agent's drives are the expression of the deficit or excess of internal resources and the reference of the agent to define its relationship with the environment. The schema to learn object affordances is integrated in an actor-critic reinforcement learning algorithm, which is the core of a motivation and reinforcement framework driving behaviour selection and learning. Its working principle is based on the capacity of perceiving changes in the environment via internal hormonal responses and of modifying the agent's behavioural patterns accordingly. To this end, the concept of reward is defined in the framework of the agent's internal physiology and is related to the condition of physiological stability introduced by Ashby, and supported by Dawkins and Meyer as a requirement for survival. In this light, the definition of the reward used for learning is defined in the physiological state, where the effect of interacting with the environment can be quantified in an ethologically consistent manner.The above ideas on motivation, behaviour selection, learning and perception have been made explicit in an architecture integrated in an simulated robotic platform. To demonstrate the reach of their validity, extensive simulation has been performed to address the affordance learning paradigm and the adaptation offered by the framework of the actor-critic. To this end, three different metrics have been proposed to measure the effect of external and internal perception on the learning and behaviour selection processes: the performance in terms of flexibility of adaptation, the physiological stability and the cycles of behaviour execution at every situation. In addition to this, the thesis has begun to frame the integration of behaviours of an appetitive and consummatory nature in a single schema. Finally, it also contributes to the arguments disambiguating the role of dopamine as a neurotransmitter in the Basal Ganglia

Formalizing affordances in situation

The representation of a perceptual scene by a computer is usually limited to numbers representing dimensions and colours. The theory of affordances attempted to provide a new way of representing an environment, with respect to a particular agent. The view was introduced as part of an entire field of psychology labeled as 'ecological,' which has since branched into computer science through the field of robotics, and formal methods. This thesis will describe the concept of affordances, review several existing formalizations, and take a brief look at applications to robotics. The formalizations put forth in the last 20 years have no agreed upon structure, only that both the agent and the environment must be taken in relation to one another. Situation theory has also been evolving since its inception in 1983 by Barwise & Perry. The theory provided a formal way to represent any arbitrary piece of information in terms of relations. This thesis will take a toy version of situation theory published in CSLI lecture notes no. 22, and add to the given ontologies. This thesis extends the given ontologies to include specialized affordance types, and individual object types. This allows for the definition of semantic objects called environments, which support a situation and a set of affordances, and niches which refer to a set of actions for an individual. Finally, a possible way for an environment to change into a new environment is suggested via the activation of an affordance

You Can\u27t Get There from Here: Movement SF and the Picaresque

This dissertation examines the crisis of authenticity in postmodern culture and argues that contemporary science fiction, specifically the subgenre of Movement SF, has evolved a unique answer to this crisis by adopting, perhaps spontaneously, the picaresque narrative structure. Postmodern fiction has a tenuous relationship with the issue of authenticity, such that the average postmodern subject is utterly without true authenticity at all, alternately victim to the socioeconomic conditions of his or her culture and to the elision of the self as a result of the homogenizing effects of advertising, television, etc. Postmodern SF also carries this bleak perception of the possibility of agency; William Gibson\u27s Sprawl and Bridge trilogies are rife with negations of human agency at the metaphorical hands of various aspects and incarnations of what Fredric Jameson terms the technological sublime. This dissertation puts forth the argument that a group of post-Eighties SF texts all participate in a spontaneous revival of the picaresque mode, using the picaresque journey and related motifs to re-authenticate subjects whose identity and agency are being erased by powerful social and economic forces exterior to and normally imperceptible by the individual. This dissertation is organized around three loosely connected parts. Part 1 attempts to define Movement SF by separating the various, often confusing marketing labels (such as cyberpunk, postcyberpunk, etc.) and extracting a cluster of core characteristics that have shaped the genre since its inception in the early 80s. Part 1 further examines how these core characteristics (or premises) of Movement SF provide fertile ground for picaresque narrative strategies. Part 2 describes in detail the picaresque as it appears in Movement SF, examining worldbuilding strategies, the persistence and evolution of tropes and motifs common to the traditional picaresque, and the generation of new tropes and motifs unique to Movement picaresques. Part 3 examines the spatial tactics used in Movement picaresque narratives to enable picaresque marginality in totalized, globalized environments. Furthermore, Part 3 examines the use of psychological plurality as an internal tactic to escape closed environments

Perception in real and artificial insects: a robotic investigation of cricket phonotaxis

The aim of this thesis is to investigate a methodology for studying percep¬ tual systems by building artificial ones. It is proposed that useful results can be obtained from detailed robotic modelling of specific sensorimotor mechanisms in lower animals. By looking at the sensory control of behaviour in simple biological organisms, and in working robots, it is argued that proper appreciation of the physical interaction of the system with the environment and the task is essential for discovering how perceptual mechanisms function. Although links to biology, and concern with perceptual competence, are fields of growing interest in Artificial Intelligence, much of the current research fails to adequately address these issues, as the model systems being built do not represent real sensorimotor problems.By analyzing what is required for a model of a system to contribute to ex¬ plaining that system, a particular approach to modeling perceptual systems is suggested. This involves choosing an appropriate target system to model, building a system that validly represents the target with respect to a particular hypothesis, and properly evaluating the behaviour of the model system to draw conclusions about the target. The viability and potential contribution of this approach is demonstrated in the design, implementation and evaluation of a mobile robot model of a hypothesised mechanism for phonotaxis in the cricket.The result is a robot that successfully locates a specific sound source under a variety of conditions, with a range of behaviour that resembles the cricket in many ways. This provides some support for the hypothesis that the neural mechanism for phonotaxis in crickets does not involve separate processing for recognition and location of the signal, as is generally supposed. It also shows the importance of un¬ derstanding the physical interaction of the system's structure with its environment in devising and implementing perceptual systems. Both these results vindicate the proposed methodology

The Question of Knowledge in Evidence-Based Design for Healthcare Facilities: Limitations and Suggestions

This is the author's accepted manuscript. The original published version can be found at http://her.sagepub.com/content/6/4/101.abstract.OBJECTIVE: To help designers and researchers and other proponents of evidence-based design (EBD) overcome limitations concerning knowledge categorization and acquisition of evidence-based design (EBD). BACKGROUND: The evidence-based design (EBD) approach for healthcare facilities has been widely embraced by both designers and researchers in recent years; however, there are some limitations concerning knowledge categorization and acquisition of EBD. These limitations include an overemphasis on empirical knowledge gained by experimental research, a narrow focus that excludes design knowledge generated outside healthcare and allied fields, and a lack of interest in empirical knowledge gained by qualitative studies. In order to overcome these limitations, the proponents of EBD must acknowledge that design knowledge relevant to healthcare design can be found in disciplines unrelated to healthcare; that design knowledge does not always need empirical validation; and that design knowledge of the semantic kind can be more easily accessed and understood through qualitative studies. CONCLUSIONS: To reassess the foundations of knowledge of EBD with moderated skepticism is necessary because there are philosophical and analytical problems yet to be overcome in delivering on the promises of EBD. To question and reassess the foundations of knowledge base of EBD is not necessarily to deny its value, but rather to stimulate a judicious and balanced appraisal of its limitations so that, in future, we are able to take necessary steps to overcome these limitations

Bodies in place : enactive cognition as development of ecological norms

Les partisans de l’approche énactive soutiennent que la cognition se constitue à travers l’histoire des différentes formes d'interaction (biologique, sensorimotrice, intercorporelle, linguistique, etc.) entre un vivant et son environnement. Ces interactions ne sont pas aléatoires, mais des activités obéissant à certaines normes que les énactivistes appellent sense-making. La cognition est, de ce point de vue, une forme de sense-making. Malgré les avantages indéniables que confère une telle perspective pour étudier la cognition, la présente thèse développe un point de vue critique par rapport à l’approche énactive et soutient qu'il est nécessaire d'approfondir notre compréhension de la dimension écologique du sense-making. Le but principal de la thèse est en conséquence de montrer que l'environnement joue un rôle encore plus important que l’approche énactive ne lui attribue habituellement. En m'engageant de manière critique dans le répertoire conceptuel de la cognition énactive, de la phénoménologie et des approches écologiques de la cognition, l’objectif de cette thèse consiste à poser les bases conceptuelles d'une approche énactive-écologique de la cognition. Pour ce faire, la thèse s’attèle à mettre de l’avant trois idées principales. La première consiste à redéfinir le concept du sense-making : contrairement à la conception qui s’est traditionnellement imposée dans le mouvement énactif, nous allons démontrer qu’il s’agit d’un phénomène de développement (et non de création) de normes. La rencontre du corps et du monde est toujours ancrée dans un champ normatif prédéfini, de sorte que nous devons réévaluer le rôle que joue l'environnement dans les processus de sense-making. En effet, si les agents se retrouvent toujours-déjà plongés dans un champ normatif (et non dans un environnement purement causal et physique), il faut alors reconnaître que l'environnement joue un rôle actif dans la constitution et l'auto-transformation des normes de sense-making. La deuxième idée poursuit dans cette veine et porte sur cette nouvelle conception de l'environnement, qui est ici défini comme un champ normatif actif, incarnant une tension entre le passé habituel du système agent-environnement et les contingences incessantes des événements du monde qui poussent le système vers leur auto-transformation et développement. La troisième idée principale de cette thèse consiste en une description holistique du champ d'action des agents (un lieu énactif) et des normes édictées (enacted) par des processus de sense-making sur le terrain (normes de lieu). Une esquisse générale du lieu énactif montre que les activités de sense-making sont liées à des processus écologiques qui enchevêtrent de multiples agents et localités matérielles dans un réseau écologique local. Ces réseaux écologiques forment une unité systémique et résiliente qui se déploie dans le temps avec les habitants du lieu, et fonctionne comme un champ normatif qui contraint et motive l'auto-transformation de chaque système agent-environnementSupporters of autonomist enactivism or the enactive approach claim that cognition is a phenomenon constituted by the historical development of different forms of interaction (biological, sensorimotor, intercorporeal, and linguistic) between living bodies and their environments. For autonomist enactivists, the nature of these interactions is not entirely predetermined by general laws of causation but by norms enacted in the historical path of the agent-environment system, and thanks to processes of sense-making. Cognition is, from the enactivist standpoint, a form of sense-making. While there are multiple advantages in holding such perspective to study mind and cognition, this thesis develops a critical point of view and argues that it is necessary to deepen our understanding of the ecological dimension of sense-making. Specifically, the thesis aims to show that the environment plays a more critical role than autonomist enactivism usually attributes to it. By drawing on and critically engaging with the conceptual repertoire of enactive cognition, phenomenology, and ecological approaches to cognition, my objective is to set the conceptual foundations for an enactive-ecological approach to cognition. For this task, I propose three interrelated ideas. The first redefines sense-making as a phenomenon of norm development. The most common descriptions of sense-making involve the emergence of meaning from raw physical matter thanks to the activity of living organisms. As norm development, by contrast, sense-making refers to a constant enactment and re-enactment of norms of interaction from other pregiven norms, previously enacted in the past of the agent-environment system. I argue that the encounter of the body and the world is permanently embedded in a pregiven normative field and never in an abstract void where raw physical interactions occur. From this standpoint, we need, however, to re-evaluate the role that the environment plays in sense-making processes. If agents find themselves immersed in normative fields and not in raw physical landscapes, then the environment has a more active role for the constitution and self-transformation of sense-making norms than autonomist enactivists have acknowledged. In this vein, the second main idea of this thesis concerns the environment as an active normative field that incarnates a tension between the habitual past of the agent-environment system and the ongoing contingencies of worldly events that push the system to their self-transformation and development. The third main idea of this thesis consists of a holistic description of the field of action of agents (enactive place) and the norms enacted by processes of sense-making in the field (place-norms). A general sketch of enactive place shows that sense-making is tied to processes that entangle multiple agents and material localities into a local ecological web. An enactive place constitutes a systemic and resilient unity that unfolds in time altogether with its inhabitants, working as a normative field that constrains and motivates the self-transformation of each agent-environment system. Bodies are therefore part of wider unities of historical development: places