Neuromuscular Mechanisms of Movement Variability: Implications for Rehabilitation and Augmentation

Although speed-accuracy trade-offs and planning and execution of rapid goaldirected movements have garnered significant research interest, far fewer studies have reported results on the lower end of the movement speed spectrum. Not only do very interesting observations exist that are unique to slow movements, but an explanation of these observations is highly relevant to motor function recovery and motor skill learning, where movements are typically slow at the initiation of therapy or learning, and movement speed increases through practice, exercise or therapy. In the first part of this thesis, based on data from nine stroke patients who underwent a month-long hybrid traditional and robotic therapy protocol, a correlation analysis shows that measures of movement quality based on minimum jerk theory for movement planning correlates significantly and strongly with clinical measures of motor impairment. In contrast, measures of movement speed lack statistical significance and show only weak to moderate correlations with clinical measures. These results constitute an important step towards establishing a much-needed bridge between clinical and robotic rehabilitation research communities. In the second part, the origins of movement intermittency or variability in slow movements are explored. A study with five healthy subjects who completed a manual circular tracking task shows that movement intermittency increases in distal direction along the arm during multi-joint movements. This result suggests that a neuromuscular noise option is favored against a submovement-based central planning alternative, as the source of variability in slow movements. An additional experimental study with eight healthy subjects who completed slow elbow flexion movements at a constant slow speed target under varying resistive torque levels demonstrates that resistive torques can significantly decrease movement speed variability. The relationship between resistive torque levels and speed variability, however, is not monotonic. This finding may constitute a basis for proper design of novel human skill augmentation methods for delicate tasks and improve motor rehabilitation and learning protocols. Finally, a neuro-musculoskeletal model of the elbow suggests that movement speed variability in slow movements cannot be solely attributed to variability in the mechanics of muscle force generation. Together, these analyses, simulations, and experiments shed light on variability in slow movements, and will inform the development of novel paradigms for robotic rehabilitation, motor skill learning and augmentation

TRAINING AND ASSESSMENT OF HAND-EYE COORDINATION WITH ELECTROENCEPHALOGRAPHY

Ph.DDOCTOR OF PHILOSOPH

Image-Guided Robot-Assisted Techniques with Applications in Minimally Invasive Therapy and Cell Biology

There are several situations where tasks can be performed better robotically rather than manually. Among these are situations (a) where high accuracy and robustness are required, (b) where difficult or hazardous working conditions exist, and (c) where very large or very small motions or forces are involved. Recent advances in technology have resulted in smaller size robots with higher accuracy and reliability. As a result, robotics is fi nding more and more applications in Biomedical Engineering. Medical Robotics and Cell Micro-Manipulation are two of these applications involving interaction with delicate living organs at very di fferent scales.Availability of a wide range of imaging modalities from ultrasound and X-ray fluoroscopy to high magni cation optical microscopes, makes it possible to use imaging as a powerful means to guide and control robot manipulators. This thesis includes three parts focusing on three applications of Image-Guided Robotics in biomedical engineering, including: Vascular Catheterization: a robotic system was developed to insert a catheter through the vasculature and guide it to a desired point via visual servoing. The system provides shared control with the operator to perform a task semi-automatically or through master-slave control. The system provides control of a catheter tip with high accuracy while reducing X-ray exposure to the clinicians and providing a more ergonomic situation for the cardiologists. Cardiac Catheterization: a master-slave robotic system was developed to perform accurate control of a steerable catheter to touch and ablate faulty regions on the inner walls of a beating heart in order to treat arrhythmia. The system facilitates touching and making contact with a target point in a beating heart chamber through master-slave control with coordinated visual feedback. Live Neuron Micro-Manipulation: a microscope image-guided robotic system was developed to provide shared control over multiple micro-manipulators to touch cell membranes in order to perform patch clamp electrophysiology. Image-guided robot-assisted techniques with master-slave control were implemented for each case to provide shared control between a human operator and a robot. The results show increased accuracy and reduced operation time in all three cases

Investigation of end-stop motion constraint for a wave energy converter

This work develops a design protocol for wave energy converter motion constraint, endstop systems. It applies the protocol by first using a numerical hydrodynamic wave energy converter (WEC) model to obtain preliminary design loads. Following a definitive set of selection criteria, comprehensive design of a system of load-bearing, helical springs is produced. A preliminary design is modeled with finite element analysis, and compared to analytical results. New dynamical collision models are conceived for impact damping systems based on spring-mass and anisotropic surface friction phenomena, by applying the concept observed on the snake ventral skin. Friction and compressive forces are correlated by classical mechanics. Finally, dimensional analysis is applied to yield design parameterization to directly compare the micro and macro influences within these distinct models, resulting in new knowledge on the physical relationships within contact interfaces and a dimensionless mechanical impedance formulationEsta dissertação desenvolve um protocolo para projetos de sistemas de restrição de movimentos associado a um limitador de fim de curso em conversores de energia das ondas. Inicialmente, é aplicado um modelo numérico hidrodinâmico para análise de cargas em um conversor de energia das ondas (WEC). Em seguida, é apresentado um conjunto definitivo de critérios de seleção, para análise de um sistema de molas helicoidais compressivas, para atenuar as forças provocadas pelos movimentos extremos da boia. Um projeto preliminar é modelado com análises de elementos finitos e comparado com os resultados analíticos. Novos tipos de modelos dinâmicos são idealizados para amortecimento do impacto, baseados em molas e no fenômeno de atrito superficial anisotrópico, aplicando o conceito observado na pele ventral de cobras. As forças de atrito e compressivas foram correlacionadas por meio de princípios de mecânica clássica. Finalmente, uma análise adimensional é utilizada para gerar a parametrização do projeto, para comparar diretamente as micro e macro influências entre esses modelos distintos, resultando em novos conhecimentos sobre as relações físicas nas interfaces de contato e uma formulação adimensional de impedância mecânica

Advanced Mobile Robotics: Volume 3

Mobile robotics is a challenging field with great potential. It covers disciplines including electrical engineering, mechanical engineering, computer science, cognitive science, and social science. It is essential to the design of automated robots, in combination with artificial intelligence, vision, and sensor technologies. Mobile robots are widely used for surveillance, guidance, transportation and entertainment tasks, as well as medical applications. This Special Issue intends to concentrate on recent developments concerning mobile robots and the research surrounding them to enhance studies on the fundamental problems observed in the robots. Various multidisciplinary approaches and integrative contributions including navigation, learning and adaptation, networked system, biologically inspired robots and cognitive methods are welcome contributions to this Special Issue, both from a research and an application perspective

Whole-hand input

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Architecture, 1992.Includes bibliographical references (p. 219-233).by David Joel Sturman.Ph.D

Treatise on Hearing: The Temporal Auditory Imaging Theory Inspired by Optics and Communication

A new theory of mammalian hearing is presented, which accounts for the auditory image in the midbrain (inferior colliculus) of objects in the acoustical environment of the listener. It is shown that the ear is a temporal imaging system that comprises three transformations of the envelope functions: cochlear group-delay dispersion, cochlear time lensing, and neural group-delay dispersion. These elements are analogous to the optical transformations in vision of diffraction between the object and the eye, spatial lensing by the lens, and second diffraction between the lens and the retina. Unlike the eye, it is established that the human auditory system is naturally defocused, so that coherent stimuli do not react to the defocus, whereas completely incoherent stimuli are impacted by it and may be blurred by design. It is argued that the auditory system can use this differential focusing to enhance or degrade the images of real-world acoustical objects that are partially coherent. The theory is founded on coherence and temporal imaging theories that were adopted from optics. In addition to the imaging transformations, the corresponding inverse-domain modulation transfer functions are derived and interpreted with consideration to the nonuniform neural sampling operation of the auditory nerve. These ideas are used to rigorously initiate the concepts of sharpness and blur in auditory imaging, auditory aberrations, and auditory depth of field. In parallel, ideas from communication theory are used to show that the organ of Corti functions as a multichannel phase-locked loop (PLL) that constitutes the point of entry for auditory phase locking and hence conserves the signal coherence. It provides an anchor for a dual coherent and noncoherent auditory detection in the auditory brain that culminates in auditory accommodation. Implications on hearing impairments are discussed as well.Comment: 603 pages, 131 figures, 13 tables, 1570 reference

Conference on Intelligent Robotics in Field, Factory, Service, and Space (CIRFFSS 1994), volume 1

The AIAA/NASA Conference on Intelligent Robotics in Field, Factory, Service, and Space (CIRFFSS '94) was originally proposed because of the strong belief that America's problems of global economic competitiveness and job creation and preservation can partly be solved by the use of intelligent robotics, which are also required for human space exploration missions. Individual sessions addressed nuclear industry, agile manufacturing, security/building monitoring, on-orbit applications, vision and sensing technologies, situated control and low-level control, robotic systems architecture, environmental restoration and waste management, robotic remanufacturing, and healthcare applications

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