812 research outputs found
Recent Advances in Motion Analysis
The advances in the technology and methodology for human movement capture and analysis over the last decade have been remarkable. Besides acknowledged approaches for kinematic, dynamic, and electromyographic (EMG) analysis carried out in the laboratory, more recently developed devices, such as wearables, inertial measurement units, ambient sensors, and cameras or depth sensors, have been adopted on a wide scale. Furthermore, computational intelligence (CI) methods, such as artificial neural networks, have recently emerged as promising tools for the development and application of intelligent systems in motion analysis. Thus, the synergy of classic instrumentation and novel smart devices and techniques has created unique capabilities in the continuous monitoring of motor behaviors in different fields, such as clinics, sports, and ergonomics. However, real-time sensing, signal processing, human activity recognition, and characterization and interpretation of motion metrics and behaviors from sensor data still representing a challenging problem not only in laboratories but also at home and in the community. This book addresses open research issues related to the improvement of classic approaches and the development of novel technologies and techniques in the domain of motion analysis in all the various fields of application
Tennis racket performance studies and the design of a novel test machine
The investigation was instigated by a growing concern from the
International Tennis Federation (ITF) that the contribution of racket technology
in the modem game of tennis might be changing the nature of the game by
making it too fast. The serve was earmarked as the most critical stroke
influencing the speed of the game, resulting in the decision to build a test
machine, which would investigate racket performance under realistic serve
conditions. In order to determine the design specifications for the machine the
following studies were performed. [Continues.
Bridging the Gap between Detection and Tracking for 3D Human Motion Recovery
The aim of this thesis is to build a system able to automatically and robustly track human motion in 3–D starting from monocular input. To this end two approaches are introduced, which tackle two different types of motion: The first is useful to analyze activities for which a characteristic pose, or key-pose, can be detected, as for example in the walking case. On the other hand the second can be used for cases in which such pose is not defined but there is a clear relation between some easily measurable image quantities and the body configuration, as for example in the skating case where the trajectory followed by a subject is highly correlated to how the subject articulates. In the first proposed technique we combine detection and tracking techniques to achieve robust 3D motion recovery of people seen from arbitrary viewpoints by a single and potentially moving camera. We rely on detecting key postures, which can be done reliably, using a motion model to infer 3D poses between consecutive detections, and finally refining them over the whole sequence using a generative model. We demonstrate our approach in the cases of golf motions filmed using a static camera and walking motions acquired using a potentially moving one. We will show that this approach, although monocular, is both metrically accurate because it integrates information over many frames and robust because it can recover from a few misdetections. The second approach is based on the fact that the articulated body models used to represent human motion typically have many degrees of freedom, usually expressed as joint angles that are highly correlated. The true range of motion can therefore be represented by latent variables that span a low-dimensional space. This has often been used to make motion tracking easier. However, learning the latent space in a problem independent way makes it non trivial to initialize the tracking process by picking appropriate initial values for the latent variables, and thus for the pose. In this thesis, it will be shown that by directly using observable quantities as latent variables, this issue can be eliminated
Trajectory solutions for a game-playing robot using nonprehensile manipulation methods and machine vision
The need for autonomous systems designed to play games, both strategy-based and
physical, comes from the quest to model human behaviour under tough and
competitive environments that require human skill at its best. In the last two decades,
and especially after the 1996 defeat of the world chess champion by a chess-playing
computer, physical games have been receiving greater attention. Robocup TM, i.e.
robotic football, is a well-known example, with the participation of thousands of
researchers all over the world. The robots created to play snooker/pool/billiards are
placed in this context. Snooker, as well as being a game of strategy, also requires
accurate physical manipulation skills from the player, and these two aspects qualify
snooker as a potential game for autonomous system development research. Although
research into playing strategy in snooker has made considerable progress using
various artificial intelligence methods, the physical manipulation part of the game is
not fully addressed by the robots created so far. This thesis looks at the different ball
manipulation options snooker players use, like the shots that impart spin to the ball in
order to accurately position the balls on the table, by trying to predict the ball
trajectories under the action of various dynamic phenomena, such as impacts.
A 3-degree of freedom robot, which can manipulate the snooker cue on a par with
humans, at high velocities, using a servomotor, and position the snooker cue on the
ball accurately with the help of a stepper drive, is designed and fabricated. [Continues.
Rehabilitation Engineering
Population ageing has major consequences and implications in all areas of our daily life as well as other important aspects, such as economic growth, savings, investment and consumption, labour markets, pensions, property and care from one generation to another. Additionally, health and related care, family composition and life-style, housing and migration are also affected. Given the rapid increase in the aging of the population and the further increase that is expected in the coming years, an important problem that has to be faced is the corresponding increase in chronic illness, disabilities, and loss of functional independence endemic to the elderly (WHO 2008). For this reason, novel methods of rehabilitation and care management are urgently needed. This book covers many rehabilitation support systems and robots developed for upper limbs, lower limbs as well as visually impaired condition. Other than upper limbs, the lower limb research works are also discussed like motorized foot rest for electric powered wheelchair and standing assistance device
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