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

Direct Animation Interfaces : an Interaction Approach to Computer Animation

Creativity tools for digital media have been largely democratised, offering a range from beginner to expert tools. Yet computer animation, the art of instilling life into believable characters and fantastic worlds, is still a highly sophisticated process restricted to the spheres of expert users. This is largely due to the methods employed: in keyframe animation dynamics are indirectly specified over abstract descriptions, while performance animation suffers from inflexibility due to a high technological overhead. The reverse trend in human-computer interaction to make interfaces more direct, intuitive, and natural to use has so far hardly touched the animation world: decades of interaction research have scarcely been linked to research and development of animation techniques. The hypothesis of this work is that an interaction approach to computer animation can inform the design and development of novel animation techniques. Three goals are formulated to illustrate the validity of this thesis. Computer animation methods and interfaces must be embedded in an interaction context. The insights this brings for designing next generation animation tools must be examined and formalised. The practical consequences for the development of motion creation and editing tools must be demonstrated with prototypes that are more direct, efficient, easy-to-learn, and flexible to use. The foundation of the procedure is a conceptual framework in the form of a comprehensive discussion of the state of the art, a design space of interfaces for time-based visual media, and a taxonomy for mappings between user and medium space-time. Based on this, an interaction-centred analysis of computer animation culminates in the concept of direct animation interfaces and guidelines for their design. These guidelines are tested in two point designs for direct input devices. The design, implementation and test of a surface-based performance animation tool takes a system approach, addressing interaction design issues as well as challenges in extending current software architectures to support novel forms of animation control. The second, a performance timing technique, shows how concepts from video browsing can be applied to motion editing for more direct and efficient animation timing

On the Utility of Representation Learning Algorithms for Myoelectric Interfacing

Electrical activity produced by muscles during voluntary movement is a reflection of the firing patterns of relevant motor neurons and, by extension, the latent motor intent driving the movement. Once transduced via electromyography (EMG) and converted into digital form, this activity can be processed to provide an estimate of the original motor intent and is as such a feasible basis for non-invasive efferent neural interfacing. EMG-based motor intent decoding has so far received the most attention in the field of upper-limb prosthetics, where alternative means of interfacing are scarce and the utility of better control apparent. Whereas myoelectric prostheses have been available since the 1960s, available EMG control interfaces still lag behind the mechanical capabilities of the artificial limbs they are intended to steer—a gap at least partially due to limitations in current methods for translating EMG into appropriate motion commands. As the relationship between EMG signals and concurrent effector kinematics is highly non-linear and apparently stochastic, finding ways to accurately extract and combine relevant information from across electrode sites is still an active area of inquiry.This dissertation comprises an introduction and eight papers that explore issues afflicting the status quo of myoelectric decoding and possible solutions, all related through their use of learning algorithms and deep Artificial Neural Network (ANN) models. Paper I presents a Convolutional Neural Network (CNN) for multi-label movement decoding of high-density surface EMG (HD-sEMG) signals. Inspired by the successful use of CNNs in Paper I and the work of others, Paper II presents a method for automatic design of CNN architectures for use in myocontrol. Paper III introduces an ANN architecture with an appertaining training framework from which simultaneous and proportional control emerges. Paper Iv introduce a dataset of HD-sEMG signals for use with learning algorithms. Paper v applies a Recurrent Neural Network (RNN) model to decode finger forces from intramuscular EMG. Paper vI introduces a Transformer model for myoelectric interfacing that do not need additional training data to function with previously unseen users. Paper vII compares the performance of a Long Short-Term Memory (LSTM) network to that of classical pattern recognition algorithms. Lastly, paper vIII describes a framework for synthesizing EMG from multi-articulate gestures intended to reduce training burden

Effizienz und Ergonomie von Multitouch-Interaktion : Studien und Prototypen zur Bewertung und Optimierung zentraler Interaktionstechniken

Die vorliegende Arbeit beschäftigt sich mit Grundfragen der Effektivität, Effizienz und Zufriedenheit von Multitouch-Interaktionen. Mithilfe einer Multitouch-Steuerung für 3D-Animation konnte gezeigt werden, dass selbst unerfahrene Multitouch-Nutzer in der Lage sind, hoch komplexe Aufgaben koordiniert und effizient zu lösen. Ein neu entwickeltes Koordinationsmaß bestätigt, dass Nutzer den Vorteil eines Multitouch nutzen, indem sie koordiniert mehrere Finger gleichzeitig für 3D-Animationen in Echtzeit einsetzen. In drei weiteren Studien zu zentralen Multitouch-Interaktionstechniken konnte gezeigt werden, dass die Originalformulierung von Fitts’ Gesetz nicht ausreicht, um die Effizienz von Multitouch-Interaktionen adäquat zu bewerten und zu analysieren. Fitts’ Gesetz ist ein Modell zur Vorhersage und Analyse von Interaktionszeiten und beinhaltet ursprünglich nur die Distanz der Interaktionsbewegung und die Zielgröße. Diese Arbeit zeigt, dass Vorhersagen mit Fitts’ Gesetz bessere Ergebnisse liefern, wenn sie neben diesen beiden Faktoren auch Bewegungsrichtung, Startpunkt der Bewegung und Neigung des Multitouch-Display berücksichtigen. Die Ergebnisse dieser Arbeitliefern Anhaltspunkte, um effiziente und benutzerfreundliche Interaktionstechniken zu entwickeln. Zudem könnten sie eingesetzt werden, um Analysen von Intertaktionstechniken für Multitouch teilautomatisch durchzuführen.This thesis deals with fundamental questions of efficiency, effectiveness and satisfaction of multitouch interactions. Using a novel multitouch interface for 3D animation it could be shown that even inexperienced multitouch users are capable of solving highly complex tasks in a coordinated and efficient way. A newly developed measure for coordination confirms that users take advantage of multitouch by using several fingers simultaneously to create a 3D real-time animation. In three additional studies on central interaction techniques for multitouch it was shown that the original Fitts’ law is not sufficient to adequately describe and analyse the efficiency of multitouch interactions. Fitts’ law is a model for the prediction and analysis of interaction time which originally only takes into account the distance of interaction movements and the target size. This work shows that predictions based on Fitts’ law provide better results when, in addition to these two factors, the direction of the movement, the starting point and the tilt of the display are considered, as well. The present results provide approaches to developing efficient interaction techniques with high usability. Furthermore, they can be used to conduct a semi-automatic analysis of interaction techniques for multitouch

Effizienz und Ergonomie von Multitouch-Interaktion : Studien und Prototypen zur Bewertung und Optimierung zentraler Interaktionstechniken

Die vorliegende Arbeit beschäftigt sich mit Grundfragen der Effektivität, Effizienz und Zufriedenheit von Multitouch-Interaktionen. Mithilfe einer Multitouch-Steuerung für 3D-Animation konnte gezeigt werden, dass selbst unerfahrene Multitouch-Nutzer in der Lage sind, hoch komplexe Aufgaben koordiniert und effizient zu lösen. Ein neu entwickeltes Koordinationsmaß bestätigt, dass Nutzer den Vorteil eines Multitouch nutzen, indem sie koordiniert mehrere Finger gleichzeitig für 3D-Animationen in Echtzeit einsetzen. In drei weiteren Studien zu zentralen Multitouch-Interaktionstechniken konnte gezeigt werden, dass die Originalformulierung von Fitts’ Gesetz nicht ausreicht, um die Effizienz von Multitouch-Interaktionen adäquat zu bewerten und zu analysieren. Fitts’ Gesetz ist ein Modell zur Vorhersage und Analyse von Interaktionszeiten und beinhaltet ursprünglich nur die Distanz der Interaktionsbewegung und die Zielgröße. Diese Arbeit zeigt, dass Vorhersagen mit Fitts’ Gesetz bessere Ergebnisse liefern, wenn sie neben diesen beiden Faktoren auch Bewegungsrichtung, Startpunkt der Bewegung und Neigung des Multitouch-Display berücksichtigen. Die Ergebnisse dieser Arbeitliefern Anhaltspunkte, um effiziente und benutzerfreundliche Interaktionstechniken zu entwickeln. Zudem könnten sie eingesetzt werden, um Analysen von Intertaktionstechniken für Multitouch teilautomatisch durchzuführen.This thesis deals with fundamental questions of efficiency, effectiveness and satisfaction of multitouch interactions. Using a novel multitouch interface for 3D animation it could be shown that even inexperienced multitouch users are capable of solving highly complex tasks in a coordinated and efficient way. A newly developed measure for coordination confirms that users take advantage of multitouch by using several fingers simultaneously to create a 3D real-time animation. In three additional studies on central interaction techniques for multitouch it was shown that the original Fitts’ law is not sufficient to adequately describe and analyse the efficiency of multitouch interactions. Fitts’ law is a model for the prediction and analysis of interaction time which originally only takes into account the distance of interaction movements and the target size. This work shows that predictions based on Fitts’ law provide better results when, in addition to these two factors, the direction of the movement, the starting point and the tilt of the display are considered, as well. The present results provide approaches to developing efficient interaction techniques with high usability. Furthermore, they can be used to conduct a semi-automatic analysis of interaction techniques for multitouch