Perception of Motion and Architectural Form: Computational Relationships between Optical Flow and Perspective

Perceptual geometry refers to the interdisciplinary research whose objectives focuses on study of geometry from the perspective of visual perception, and in turn, applies such geometric findings to the ecological study of vision. Perceptual geometry attempts to answer fundamental questions in perception of form and representation of space through synthesis of cognitive and biological theories of visual perception with geometric theories of the physical world. Perception of form, space and motion are among fundamental problems in vision science. In cognitive and computational models of human perception, the theories for modeling motion are treated separately from models for perception of form.Comment: 10 pages, 13 figures, submitted and accepted in DoCEIS'2012 Conference: http://www.uninova.pt/doceis/doceis12/home/home.ph

Human Visual Field and Navigational Strategies

In this study we use a particular virtual reality environment to investigate spatial navigation in human adults in two viewing conditions. In the first, participants could simultaneously see both landmarks of the virtual environment which inform about the location of the goal (simultaneous vision). In the second, participants could see only one landmark at a time (sequential vision). Basically, conditions differed with regard to the amplitude of the visual fields, which might influence the strategy adopted by the participant to navigate in the virtual space and locate the goal. When people have visual access to both landmarks, they can use all relevant information to navigate. However, when people see only one landmark at a time, they need to integrate the partial viewings of the environment in order to reconstruct the visual space. Consequently, simultaneous and sequential vision tasks involve different cognitive demands..

Visual perception related to head control

Visual perception interferes with the movement of the head, before the maturation of vision, related to the perception of image, place, space, and distance of objects. The present study aimed to detail the importance of this cognitive factor in the psychomotor development related to vision. The methodology used was a literature review, using the descriptors "visual perception", "head control", "postural control" and "sensory information" in the National Library of Medicine (PubMed), Scientific Electronic Library Online (SciELO) and CAPES Periodicals databases. From the data survey, it was evident that visual perception has a great influence on head motor control, and is related to the later development of visual cognitive skills. There is also the need for further research in the meantime, due to the scarce amount of material available

The multisensory body revealed through its cast shadows

One key issue when conceiving the body as a multisensory object is how the cognitive system integrates visible instances of the self and other bodies with one\u2019s own somatosensory processing, to achieve self-recognition and body ownership. Recent research has strongly suggested that shadows cast by our own body have a special status for cognitive processing, directing attention to the body in a fast and highly specific manner. The aim of the present article is to review the most recent scientific contributions addressing how body shadows affect both sensory/perceptual and attentional processes. The review examines three main points: (1) body shadows as a special window to investigate the construction of multisensory body perception; (2) experimental paradigms and related findings; (3) open questions and future trajectories. The reviewed literature suggests that shadows cast by one\u2019s own body promote binding between personal and extrapersonal space and elicit automatic orienting of attention toward the bodypart casting the shadow. Future research should address whether the effects exerted by body shadows are similar to those observed when observers are exposed to other visual instances of their body. The results will further clarify the processes underlying the merging of vision and somatosensation when creating body representations

Instrumentation and robotic image processing using top-down model control

A top-down image processing scheme is described. A three-dimensional model of a robotic working environment, with robot manipulators, workpieces, cameras, and on-the-scene visual enhancements is employed to control and direct the image processing, so that rapid, robust algorithms act in an efficient manner to continually update the model. Only the model parameters are communicated, so that savings in bandwidth are achieved. This image compression by modeling is especially important for control of space telerobotics. The background for this scheme lies in an hypothesis of human vision put forward by the senior author and colleagues almost 20 years ago - the Scanpath Theory. Evidence was obtained that repetitive sequences of saccadic eye movements, the scanpath, acted as the checking phase of visual pattern recognition. Further evidence was obtained that the scanpaths were apparently generated by a cognitive model and not directly by the visual image. This top-down theory of human vision was generalized in some sense to the frame in artificial intelligence. Another source of the concept arose from bioengineering instrumentation for measuring the pupil and eye movements with infrared video cameras and special-purpose hardware

Computationally rendered painterly portrait spaces

This work is ongoing output from research work by Steve DiPaola that attempts to build a computational painting system (called ‘painterly’) that allows aspects of art (the creative human act of fine art painting) and science (cognition, vision and perception; as well as computational design) to both enhance and validate each other. The research takes a novel approach to non photorealistic rendering (NPR) which relies on parameterizing a semantic knowledge space of how a human painter paints, that is, the creative and cognitive process

Cognitive Robots for Social Interactions

One of my goals is to work towards developing Cognitive Robots, especially with regard to improving the functionalities that facilitate the interaction with human beings and their surrounding objects. Any cognitive system designated for serving human beings must be capable of processing the social signals and eventually enable efficient prediction and planning of appropriate responses. My main focus during my PhD study is to bridge the gap between the motoric space and the visual space. The discovery of the mirror neurons ([RC04]) shows that the visual perception of human motion (visual space) is directly associated to the motor control of the human body (motor space). This discovery poses a large number of challenges in different fields such as computer vision, robotics and neuroscience. One of the fundamental challenges is the understanding of the mapping between 2D visual space and 3D motoric control, and further developing building blocks (primitives) of human motion in the visual space as well as in the motor space. First, I present my study on the visual-motoric mapping of human actions. This study aims at mapping human actions in 2D videos to 3D skeletal representation. Second, I present an automatic algorithm to decompose motion capture (MoCap) sequences into synergies along with the times at which they are executed (or "activated") for each joint. Third, I proposed to use the Granger Causality as a tool to study the coordinated actions performed by at least two units. Recent scientific studies suggest that the above "action mirroring circuit" might be tuned to action coordination rather than single action mirroring. Fourth, I present the extraction of key poses in visual space. These key poses facilitate the further study of the "action mirroring circuit". I conclude the dissertation by describing the future of cognitive robotics study

An investigation into usability and exclusivity issues of digital programmable thermostats

This is the pre-print version of the Article - Copyright @ 2011 Taylor & FrancisWith nearly 60% of domestic energy consumption relating to space heating, the interaction between users and their heating controls is crucial in reducing consumption. Yet, many heating controls are complex and exclude people due to the demands placed upon their capabilities in terms of vision, reach, dexterity and thinking. This study explores the scale of and reasons for user exclusion in relation to digital programmable thermostats. The Exclusion Calculator was used to estimate the percentage of the population excluded from the use of three products. Full user testing was then conducted to elicit specific usability problems of the devices. The participants were a group of 14 younger users (aged 24–44) and 10 older users (aged 62–75). The exclusion calculations underestimated the actual exclusion significantly for both age ranges (p<0.05). None of the older users were able to complete the programming of the thermostats. Additionally, the cognitive demands of these systems were considered using a subjective workload assessment method, based on the NASA Task Load Index, and were found to be excessive. In conclusion, this study makes recommendations to facilitate the design of more inclusive digital programmable thermostats. It is argued that such changes could result in reductions in domestic heat energy consumption.This work is funded by the ESPRC and Buro Happold