44 research outputs found
Humanoid Robots
For many years, the human being has been trying, in all ways, to recreate the complex mechanisms that form the human body. Such task is extremely complicated and the results are not totally satisfactory. However, with increasing technological advances based on theoretical and experimental researches, man gets, in a way, to copy or to imitate some systems of the human body. These researches not only intended to create humanoid robots, great part of them constituting autonomous systems, but also, in some way, to offer a higher knowledge of the systems that form the human body, objectifying possible applications in the technology of rehabilitation of human beings, gathering in a whole studies related not only to Robotics, but also to Biomechanics, Biomimmetics, Cybernetics, among other areas. This book presents a series of researches inspired by this ideal, carried through by various researchers worldwide, looking for to analyze and to discuss diverse subjects related to humanoid robots. The presented contributions explore aspects about robotic hands, learning, language, vision and locomotion
From locomotion to cognition: Bridging the gap between reactive and cognitive behavior in a quadruped robot
The cognitivistic paradigm, which states that cognition is a result of computation with symbols that represent the world, has been challenged by many. The opponents have primarily criticized the detachment from direct interaction with the world and pointed to some fundamental problems (for instance the symbol grounding problem). Instead, they emphasized the constitutive role of embodied interaction with the environment. This has motivated the advancement of synthetic methodologies: the phenomenon of interest (cognition) can be studied by building and investigating whole brain-body-environment systems. Our work is centered around a compliant quadruped robot equipped with a multimodal sensory set. In a series of case studies, we investigate the structure of the sensorimotor space that the application of different actions in different environments by the robot brings about. Then, we study how the agent can autonomously abstract the regularities that are induced by the different conditions and use them to improve its behavior. The agent is engaged in path integration, terrain discrimination and gait adaptation, and moving target following tasks. The nature of the tasks forces the robot to leave the ``here-and-now'' time scale of simple reactive stimulus-response behaviors and to learn from its experience, thus creating a ``minimally cognitive'' setting. Solutions to these problems are developed by the agent in a bottom-up fashion. The complete scenarios are then used to illuminate the concepts that are believed to lie at the basis of cognition: sensorimotor contingencies, body schema, and forward internal models. Finally, we discuss how the presented solutions are relevant for applications in robotics, in particular in the area of autonomous model acquisition and adaptation, and, in mobile robots, in dead reckoning and traversability detection
Ontogeny and Adaptation: A Cross-Sectional Study of Primate Limb Elements
How primates achieve their adult skeletal form can be ascribed to two broad biological
mechanisms: genetic inheritance, where morphological characters are regulated by an individual's
phenotype over development; and plastic adaptation, where morphology responds to extrinsic
factors engendered by the physical environment. While skeletal morphology should reflect an
individual’s ecological demands throughout its life, only a limited amount of published research
has considered how ontogeny and locomotor behaviour influence limb element form together. This
thesis presents an investigation of long bone cross-sectional shape, size and strength, to inform
how five catarrhine taxa adapt their limbs over development, and further, evaluate which limb
regions more readily emit signals of plasticity or constraint along them. The sample includes Pan,
Gorilla, Pongo, Hylobatidae and Macaca, subdivided into three developmental stages: infancy,
juvenility and adulthood. Three-dimensional models of four upper (humerus and ulna) and lower
(femur and tibia) limb elements were generated using a laser scanner and sectioned at proximal,
midshaft and distal locations along each diaphysis. Three methods were used to compare geometry
across the sample: 1) principal and anatomical axis ratios served as indices of section circularity,
2) polar section moduli evaluated relative strength between limb sections and 3) a geometric
morphometric approach was developed to define section form. The results demonstrated that
irrespective of taxonomic affinity, forelimb elements serve as strong indicators of posture and
locomotor ontogenetic transitions, while hindlimb form is more reflective of body size and
developmental shifts in body mass. Moreover, geometric variation at specific regions like the midhumerus
was indistinguishable across all infant taxa in the sample, only exhibiting posture-specific
signals among mature groups, while sections like the distal ulna exhibited little or no intraspecific
variation over development. Identifying patterns of plasticity and constraint across taxonomic and
developmental groups informs how limb cross-sections either allometrically or isometrically scale
their form as they grow. These findings have direct implications to extant and extinct primate
research pertaining to body mass estimation, functional morphology and behavioural ecology
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Bio-inspired soft robotic systems: Exploiting environmental interactions using embodied mechanics and sensory coordination
Despite the widespread development of highly intelligent robotic systems exhibiting great precision, reliability, and dexterity, robots remain incapable of performing basic manipulation tasks that humans take for granted. Manipulation in unstructured environments continues to be acknowledged as a significant challenge. Soft robotics, the use of less rigid materials in robots, has been proposed as one means of addressing these limitations. The technique enables more compliant interactions with the environment, allowing for increasingly adaptive behaviours better suited to more human-centric applications.
Embodied intelligence is a biologically inspired concept in which intelligence is a function of the entire system, not only the controller or `brain'. This thesis focuses on the use of embodied intelligence for the development of soft robots, with a particular focus on how it can aid both perception and adaptability. Two main hypotheses are raised: first, that the mechanical design and fabrication of soft-rigid hybrid robots can enable increasingly environmentally adaptive behaviours, and second, that sensing materials and morphology can provide intelligence that assists perception through embodiment. A number of approaches and frameworks for the design and development of embodied systems are presented that address these hypotheses.
It is shown how embodiment in soft sensor morphology can be used to perform localised processing and thereby distribute the intelligence over the body of a system. Specifically in soft robots, sensor morphology utilises the directional deformations created by interactions with the environment to aid in perception. Building on and formalising these ideas, a number of morphology-based frameworks are proposed for detecting different stimuli.
The multifaceted role of materials in soft robots is demonstrated through the development of materials capable of both sensing and changes in material property. Such materials provide additional functionality beyond their integral scaffolding and static mechanical characteristics. In particular, an integrated material has been created exhibiting both sensing capabilities and also variable stiffness and `tack’ force, thereby enabling complex single-point grasping.
To maximise the intelligence that can be gained through embodiment, a design approach to soft robots, `soft-rigid hybrid' design is introduced. This approach exploits passive behaviours and body dynamics to provide environmentally adaptive behaviours and sensing. It is leveraged by multi-material 3D printing techniques and novel approaches and frameworks for designing mechanical structures.
The findings in this thesis demonstrate that an embodied approach to soft robotics provides capabilities and behaviours that are not currently otherwise achievable. Utilising the concept of `embodiment' results in softer robots with an embodied intelligence that aids perception and adaptive behaviours, and has the potential to bring the physical abilities of robots one step closer to those of animals and humans.EPSR