Analysis domain model for shared virtual environments

The field of shared virtual environments, which also encompasses online games and social 3D environments, has a system landscape consisting of multiple solutions that share great functional overlap. However, there is little system interoperability between the different solutions. A shared virtual environment has an associated problem domain that is highly complex raising difficult challenges to the development process, starting with the architectural design of the underlying system. This paper has two main contributions. The first contribution is a broad domain analysis of shared virtual environments, which enables developers to have a better understanding of the whole rather than the part(s). The second contribution is a reference domain model for discussing and describing solutions - the Analysis Domain Model

A Perspective on Cephalopods Mimicry and Bioinspired Technologies toward Proprioceptive Autonomous Soft Robots

Octopus skin is an amazing source of inspiration for bioinspired sensors, actuators and control solutions in soft robotics. Soft organic materials, biomacromolecules and protein ingredients in octopus skin combined with a distributed intelligence, result in adaptive displays that can control emerging optical behavior, and 3D surface textures with rough geometries, with a remarkably high control speed (≈ms). To be able to replicate deformable and compliant materials capable of translating mechanical perturbations in molecular and structural chromogenic outputs, could be a glorious achievement in materials science and in the technological field. Soft robots are suitable platforms for soft multi-responsive materials, which can provide them with improved mechanical proprioception and related smarter behaviors. Indeed, a system provided with a “learning and recognition” functions, and a constitutive “mechanical” and “material intelligence” can result in an improved morphological adaptation in multi-variate environments responding to external and internal stimuli. This review aims to explore challenges and opportunities related to smart and chromogenic responsive materials for adaptive displays, reconfigurable and programmable soft skin, proprioceptive sensing system, and synthetic nervous control units for data processing, toward autonomous soft robots able to communicate and interact with users in open-world scenarios

Mental content : consequences of the embodied mind paradigm

The central difference between objectivist cognitivist semantics and embodied cognition consists in the fact that the latter is, in contrast to the former, mindful of binding meaning to context-sensitive mental systems. According to Lakoff/Johnson's experientialism, conceptual structures arise from preconceptual kinesthetic image-schematic and basic-level structures. Gallese and Lakoff introduced the notion of exploiting sensorimotor structures for higherlevel cognition. Three different types of X-schemas realise three types of environmentally embedded simulation: Areas that control movements in peri-personal space; canonical neurons of the ventral premotor cortex that fire when a graspable object is represented; the firing of mirror neurons while perceiving certain movements of conspecifics. ..

The Effects of Visuomotor Calibration to the Perceived Space and Body, through Embodiment in Immersive Virtual Reality

We easily adapt to changes in the environment that involve cross-sensory discrepancies (e.g., between vision and proprioception). Adaptation can lead to changes in motor commands so that the experienced sensory consequences are appropriate for the new environment (e.g., we program a movement differently while wearing prisms that shift our visual space). In addition to these motor changes, perceptual judgments of space can also be altered (e.g., how far can I reach with my arm?). However, in previous studies that assessed perceptual judgments of space after visuomotor adaptation, the manipulation was always a planar spatial shift, whereas changes in body perception could not directly be assessed. In this study, we investigated the effects of velocity-dependent (spatiotemporal) and spatial scaling distortions of arm movements on space and body perception, taking advantage of immersive virtual reality. Exploiting the perceptual illusion of embodiment in an entire virtual body, we endowed subjects with new spatiotemporal or spatial 3D mappings between motor commands and their sensory consequences. The results imply that spatiotemporal manipulation of 2 and 4 times faster can significantly change participants’ proprioceptive judgments of a virtual object’s size without affecting the perceived body ownership, although it did affect the agency of the movements. Equivalent spatial manipulations of 11 and 22 degrees of angular offset also had a significant effect on the perceived virtual object’s size; however, the mismatched information did not affect either the sense of body ownership or agency. We conclude that adaptation to spatial and spatiotemporal distortion can similarly change our perception of space, although spatiotemporal distortions can more easily be detected

Direct Manipulation Of Virtual Objects

Interacting with a Virtual Environment (VE) generally requires the user to correctly perceive the relative position and orientation of virtual objects. For applications requiring interaction in personal space, the user may also need to accurately judge the position of the virtual object relative to that of a real object, for example, a virtual button and the user\u27s real hand. This is difficult since VEs generally only provide a subset of the cues experienced in the real world. Complicating matters further, VEs presented by currently available visual displays may be inaccurate or distorted due to technological limitations. Fundamental physiological and psychological aspects of vision as they pertain to the task of object manipulation were thoroughly reviewed. Other sensory modalities--proprioception, haptics, and audition--and their cross-interactions with each other and with vision are briefly discussed. Visual display technologies, the primary component of any VE, were canvassed and compared. Current applications and research were gathered and categorized by different VE types and object interaction techniques. While object interaction research abounds in the literature, pockets of research gaps remain. Direct, dexterous, manual interaction with virtual objects in Mixed Reality (MR), where the real, seen hand accurately and effectively interacts with virtual objects, has not yet been fully quantified. An experimental test bed was designed to provide the highest accuracy attainable for salient visual cues in personal space. Optical alignment and user calibration were carefully performed. The test bed accommodated the full continuum of VE types and sensory modalities for comprehensive comparison studies. Experimental designs included two sets, each measuring depth perception and object interaction. The first set addressed the extreme end points of the Reality-Virtuality (R-V) continuum--Immersive Virtual Environment (IVE) and Reality Environment (RE). This validated, linked, and extended several previous research findings, using one common test bed and participant pool. The results provided a proven method and solid reference points for further research. The second set of experiments leveraged the first to explore the full R-V spectrum and included additional, relevant sensory modalities. It consisted of two full-factorial experiments providing for rich data and key insights into the effect of each type of environment and each modality on accuracy and timeliness of virtual object interaction. The empirical results clearly showed that mean depth perception error in personal space was less than four millimeters whether the stimuli presented were real, virtual, or mixed. Likewise, mean error for the simple task of pushing a button was less than four millimeters whether the button was real or virtual. Mean task completion time was less than one second. Key to the high accuracy and quick task performance time observed was the correct presentation of the visual cues, including occlusion, stereoscopy, accommodation, and convergence. With performance results already near optimal level with accurate visual cues presented, adding proprioception, audio, and haptic cues did not significantly improve performance. Recommendations for future research include enhancement of the visual display and further experiments with more complex tasks and additional control variables

Mechanisms and functions of the nucleus as a mechano-controller of cell contractility and migration plasticity

Living tissues are crowded and dynamic environments, in which signalling molecules and physical forces constantly act on single cells. To ensure correct tissue development and homeostasis, cells function like small processors: they measure and integrate the various mechano-chemical inputs they receive from their surrounding. As an output, cells translate this information into specific signalling pathways controlling their behavior, cell specification or their physical properties, among others. %Cells can detect changes in chemicals and signalling molecules thanks to specific receptors on their surface, and the associated signalling cascades have been well characterized. In particular, as tissues are built, when external stresses are applied, or when cells rearrange and move, single cells can undergo dynamic shape deformations. Previous studies showed that large cell deformations in confined environments control cellular contractility by tuning myosin II motor protein activity and can transform various cell types into a novel amoeboid phenotype, termed stable-bleb. Still, how single cells can sense shape changes and, as a consequence, tune myosin II activity and cell behaviour remained unknown. Here, by combining planar micro-confinement assays with live cell fluorescence microscopy and quantitative image analysis, we performed a systematic study to characterize the response of progenitor stem cells derived from zebrafish embryos to mechanical shape deformations. By quantifying cellular contractility levels in various conditions and by interfering with specific signalling pathway, we then aimed to identify the mechano-sensitive mechanism that allows cells to sense and respond to shape changes. We found that cells can measure different degrees of confinement, which accordingly defines their contractility set-point. We discovered that the nucleus, the largest cellular organelle, acts as an intracellular mechano-sensor for large cell shape changes. Nucleus deformation induced an unfolding of the inner nuclear membrane, which controls the activity of cytosolic phospholipase A2 (cPLA2) in the nucleus. When active, cPLA2 triggers the release of arachidonic acid that activates myosin II through the Rho/ROCK pathway. As a result, the nucleus allows single cells to accurately and dynamically sense shape deformations and controls cellular contractility and migration plasticity under external force load. This process, further equips cells with an "escape reflex mechanism" that allows migration away from confined environments. Moreover, the combination of inner nuclear membrane unfolding and intracellular nucleus positioning, allows cells to sense and distinguish different shape deformations, as anisotropic cell compression versus isotropic swelling, through the same mechano-sensitive pathway. Our data support that the nucleus establishes a functional module for cellular mechano-transduction, enabling cells to sense and interpret different types of shape changes and to dynamically adapt their behavior to mechanical forces in the 3D microenvironment.Los tejidos son estructuras compactas y dinámicas, en las que moléculas de señalización y fuerzas físicas actúan constantemente sobre células individuales. Para garantizar el correcto desarrollo y homeostasis de los tejidos, las células funcionan como pequeños procesadores: miden e integran las diversas señales mecano-químicas que reciben de su entorno. Como resultado, las células traducen esta información en vías de señalización específicas que controlan su comportamiento, la especificación celular o sus propiedades físicas, entre otras. Concretamente, células individuales pueden experimentar deformaciones dinámicas de su morfología durante distintos procesos, ya sea durante la formación de los tejidos, la aplicación de tensiones externas o la reorganización y motilidad celular. Según estudios anteriores, las deformaciones celulares causadas por entornos confinados controlan la contractilidad celular mediante la regulación de la actividad de la proteína miosina II. De éste modo, las células adoptan un fenotipo ameboide, denominado stable-bleb. Éste fenómeno se observò en varios tipos celulares pero aún se desconoce cómo las células individuales pueden percibir los cambios de forma y, en consecuencia, ajustar la actividad de la miosina II y su comportamiento. En éste trabajo, hemos combinado el micro-confinamiento planar de células vivas con microscopia fluorescente y el análisis cuantitativo de las imágenes para realizar un estudio sistemático de caracterización de la respuesta celular a deformaciones mecánicas en células embrionarias de pez cebra. Mediante la cuantificación de los niveles de contractilidad celular en diversas condiciones y la interferencia con vías de señalización específicas, pretendemos identificar el mecanismo mecanosensitivo que permite a las células detectar y responder a los cambios de forma. Los resultados nos mostraron que las células pueden medir diferentes grados de confinamiento y en consecuencia ajustar sus contractilidad. Descubrimos que el núcleo, el mayor orgánulo celular, actúa como un mecanosensor intracelular para grandes cambios de forma celular. La deformación del núcleo induce el despliegue de la membrana nuclear interna, que controla la actividad de la fosfolipasa A2 citosólica (cPLA$_2$) en el núcleo. Cuando se encuentra activo, el cPLA$_2$ desencadena la liberación de ácido araquidónico que a su vez activa la miosina II a través de Rho/ROCK. Como resultado, el núcleo permite a la célula percibir sus forma y deformaciones dinámicas, y controlar la contractilidad celular y la plasticidad de la migración bajo fuerzas externas. Este proceso, además, dota a las células con un "reflejo de fuga" que permite la migración fuera de entornos confinados. Además, la combinación del despliegue de la membrana nuclear interna con el posicionamiento intracelular del núcleo, permite a las células percibir y distinguir diferentes tipos de deformación, tales como la compresión anisotrópica o la hinchazón isotrópica, a través de la misma vía mecanosensitiva. Nuestros datos sugieren que el núcleo establece un módulo funcional para la mecano-transducción celular, permitiendo a las células percibir e interpretar diferentes tipos de deformación y adaptar su comportamiento de manera dinámica frente a las fuerzas mecánicas de su microambiente.Postprint (published version

Immunitary Gaming: Mapping the First-Person Shooter

Videogames have been theorised as an action-based medium. The original contribution to knowledge this thesis makes is to reconfigure this claim by considering popular multiplayer FPS games as reaction-based – particularly, immune reactions. I take up Roberto Esposito’s claim that the individual in contemporary biopolitics is defined negatively against the other, controlled and ultimately negated via their reactions to power’s capacity to incessantly generate threats. By inciting insecurity and self-protective gestures, FPS games like Activision’s Call of Duty franchise and EA’s Battlefield series vividly dramatise Esposito’s thought, producing an immunitary gaming. Immunitary Gaming locates the FPS within key moments of change as well as evolution in Western image systems including the emergence of linear perspective, cartography and the early years of the cinema. The FPS appropriates these image systems, but also alters their politics. Giorgio Agamben has argued that the apparatuses of late modernity no longer subjectify like their forebears, but desubjectify the individual, producing an impotent neoliberal body politic. I trace a similar development here. My work also seeks to capture the player’s movements via autoethnographic writing that communicates the viscerally and intensity of the experience. The FPS is framed as capable of giving insight into both the present and the future of our technological and political milieu and ‘sensorium,’ in Walter Benjamin’s terms. In its valorisation of the individual and production of insecurity to incite action, this project argues that the FPS is a symbolic form of immunitary neoliberal governmentality

WRITING UTOPIA NOW: Utopian Poetics In The Work Of Theresa Hak Kyung Cha

This thesis examines Theresa Hak Kyung Cha’s DICTEE (1982), Audience Distant Relative (1977) and Reveillé dans la Brume (Awakened in the Mist) (1977). The premise of the thesis is an exploration of the various ways in which these works both perform and gesture toward the possibility of a ‘utopian’ experience of nonalienation. In Cha’s vocabulary, this takes the form of ‘interfusion’ and is related to the role of the artist as alchemist. Cha employs formal and linguistic innovations in her text, mail art and performance works to invite active participation from her readers and audience in a gesture toward embodied intersubjectivity. Her grappling with the challenges relating to the articulation of subjectivity place her work at the centre of contemporary critical debates around subjectivity and innovative poetics. In particular, recent scholarship on race and the poetic avant-garde has called for cross-disciplinary approaches to reading DICTEE as a text that explores the intersections of subjectivity and its performance in contemporary innovative poetics. Developing a theory of Utopian Poetics from my reading of Ernst Bloch’s utopian philosophy, I explore the ways in which DICTEE and Cha’s other works perform a yearning for non-alienated subjectivity that remains necessarily open and incomplete. My reading of DICTEE, in particular, is primarily informed by my own practices of yoga and meditation, and these practices form the basis of both my scholarly and creative engagements with this research. This scholarly thesis comprises Part 1 of a two-part submission. Part 2 comprises my own creative experiments with UtopianPoetics

Redesigning the human-robot interface : intuitive teleoperation of anthropomorphic robots

textA novel interface for robotic teleoperation was developed to enable accurate and highly efficient teleoperation of the Industrial Reconfigurable Anthropomorphic Dual-arm (IRAD) system and other robotic systems. In order to achieve a revolutionary increase in operator productivity, the bilateral/master-slave approach must give way to shared autonomy and unilateral control; autonomy must be employed where possible, and appropriate sensory feedback only where autonomy is impossible; and today’s low-information/high feedback model must be replaced by one that emphasizes feedforward precision and minimal corrective feedback. This is emphasized for task spaces outside of the traditional anthropomorphic scale such as mobile manipulation (i.e. large task spaces) and high precision tasks (i.e. very small task spaces). The system is demonstrated using an anthropomorphically dimensioned industrial manipulator working in task spaces from one meter to less than one millimeter, in both simulation and hardware. This thesis discusses the design requirements and philosophy of this interface, provides a summary of prototype teleoperation hardware, simulation environment, test-bed hardware, and experimental results.Mechanical Engineerin