The Development of an assistive chair for elderly with sit to stand problems

A thesis submitted to the University of Bedfordshire in partial fulfilment of the requirements for the degree of Doctor of PhilosophyStanding up from a seated position, known as sit-to-stand (STS) movement, is one of the most frequently performed activities of daily living (ADLs). However, the aging generation are often encountered with STS issues owning to their declined motor functions and sensory capacity for postural control. The motivated is rooted from the contemporary market available STS assistive devices that are lack of genuine interaction with elderly users. Prior to the software implementation, the robot chair platform with integrated sensing footmat is developed with STS biomechanical concerns for the elderly. The work has its main emphasis on recognising the personalised behavioural patterns from the elderly users’ STS movements, namely the STS intentions and personalised STS feature prediction. The former is known as intention recognition while the latter is defined as assistance prediction, both achieved by innovative machine learning techniques. The proposed intention recognition performs well in multiple subjects scenarios with different postures involved thanks to its competence of handling these uncertainties. To the provision of providing the assistance needed by the elderly user, a time series prediction model is presented, aiming to configure the personalised ground reaction force (GRF) curve over time which suggests successful movement. This enables the computation of deficits between the predicted oncoming GRF curve and the personalised one. A multiple steps ahead prediction into the future is also implemented so that the completion time of actuation in reality is taken into account

Relation of muscular contractions to mechanical deformation in the human tibia during different locomotive activities

As one of the major hard tissue in humans and most vertebrates, the skeleton, generally referring to bone, provides the essential frame to support the body and to thus permit locomotion. Considering the functional requirements of bones across different species, e.g. from rats to dinosaurs, or during different growth periods, e.g. from embryo to old age, it is not difficult to conceive that bones adapt to the experienced mechanical environment. In fact, mechanically regulated bone modeling and remodeling is one of the major means to maintain regular bone metabolism. The findings on the bone adaptation to the mechanical environment have been well theorized by Julius Wolff in 1890s [1] as ‘Wolff’s law’ and refined later by Harold Frost as ‘mechanostat’ [2-4]. Evidence from numerous animal studies in the past revealed the adaptation process of the bones to the well-defined artificial mechanical environment and suggested certain relationship between the adaptation in relation to the types of loading, e.g. loading amplitude, loading cycle, loading frequency and so on [5-8]. Conversely, bone degradation was generally observed during disuse, e.g. prolonged bed rest [9], or in the microgravity environment during space flight [10]. Indeed, the best way to further our understanding in this adaptation process is to quantitatively study the mechanical loading on bone during daily locomotor activities. However, this is still rather challenging due to technical difficulties. More importantly, the mechanical load on bones can vary greatly across individuals or species, as the variance between the body size, locomotor pattern and speed

Forensic odontology: Assessing bite wounds to determine the role of teeth in piscivorous fishes

Teeth facilitate the acquisition and processing of food in most vertebrates. However, relatively little is known about the functions of the diverse tooth morphologies observed in fishes. Piscivorous fishes (fish-eating fish) are crucial in shaping community structure and rely on their oral teeth to capture and/or process prey. However, how teeth are utilized in capturing and/or processing prey remains unclear. Most studies have determined the function of teeth by assessing morphological traits. The behavior during feeding, however, is seldom quantified. Here, we describe the function of teeth within piscivorous fishes by considering how morphological and behavioral traits interact during prey capture and processing. This was achieved through aquarium-based performance experiments, where prey fish were fed to 12 species of piscivorous fishes. Building on techniques in forensic odontology, we incorporate a novel approach to quantify and categorize bite damage on prey fish that were extracted from the piscivore’s stomachs immediately after being ingested. We then assess the significance of morphological and behavioral traits in determining the extent and severity of damage inflicted on prey fish. Results show that engulfing piscivores capture their prey whole and head-first. Grabbing piscivores capture prey tail-first using their teeth, process them using multiple headshakes and bites, before spitting them out, and then re-capturing prey head-first for ingestion. Prey from engulfers sustained minimal damage, whereas prey from grabbers sustained significant damage to the epaxial musculature. Within grabbers, headshakes were significantly associated with more severe damage categories. Headshaking behavior damages the locomotive muscles of prey, presumably to prevent escape. Compared to non-pharyngognaths, pharyngognath piscivores inflict significantly greater damage to prey. Overall, when present, oral jaw teeth appear to be crucial for both prey capture and processing (immobilization) in piscivorous fishes

Human Activity Recognition and Control of Wearable Robots

abstract: Wearable robotics has gained huge popularity in recent years due to its wide applications in rehabilitation, military, and industrial fields. The weakness of the skeletal muscles in the aging population and neurological injuries such as stroke and spinal cord injuries seriously limit the abilities of these individuals to perform daily activities. Therefore, there is an increasing attention in the development of wearable robots to assist the elderly and patients with disabilities for motion assistance and rehabilitation. In military and industrial sectors, wearable robots can increase the productivity of workers and soldiers. It is important for the wearable robots to maintain smooth interaction with the user while evolving in complex environments with minimum effort from the user. Therefore, the recognition of the user's activities such as walking or jogging in real time becomes essential to provide appropriate assistance based on the activity. This dissertation proposes two real-time human activity recognition algorithms intelligent fuzzy inference (IFI) algorithm and Amplitude omega ($A \omega$) algorithm to identify the human activities, i.e., stationary and locomotion activities. The IFI algorithm uses knee angle and ground contact forces (GCFs) measurements from four inertial measurement units (IMUs) and a pair of smart shoes. Whereas, the $A \omega$ algorithm is based on thigh angle measurements from a single IMU. This dissertation also attempts to address the problem of online tuning of virtual impedance for an assistive robot based on real-time gait and activity measurement data to personalize the assistance for different users. An automatic impedance tuning (AIT) approach is presented for a knee assistive device (KAD) in which the IFI algorithm is used for real-time activity measurements. This dissertation also proposes an adaptive oscillator method known as amplitude omega adaptive oscillator ($A\omega AO$) method for HeSA (hip exoskeleton for superior augmentation) to provide bilateral hip assistance during human locomotion activities. The $A \omega$ algorithm is integrated into the adaptive oscillator method to make the approach robust for different locomotion activities. Experiments are performed on healthy subjects to validate the efficacy of the human activities recognition algorithms and control strategies proposed in this dissertation. Both the activity recognition algorithms exhibited higher classification accuracy with less update time. The results of AIT demonstrated that the KAD assistive torque was smoother and EMG signal of Vastus Medialis is reduced, compared to constant impedance and finite state machine approaches. The $A\omega AO$ method showed real-time learning of the locomotion activities signals for three healthy subjects while wearing HeSA. To understand the influence of the assistive devices on the inherent dynamic gait stability of the human, stability analysis is performed. For this, the stability metrics derived from dynamical systems theory are used to evaluate unilateral knee assistance applied to the healthy participants.Dissertation/ThesisDoctoral Dissertation Aerospace Engineering 201

Promoting a healthy ageing workforce: use of Inertial Measurement Units to monitor potentially harmful trunk posture under actual working conditions

Musculoskeletal disorders, particularly those involving the low back, represent a major health concern for workers, and originate significant consequences for the socio-economic system. As the average age of the population is gradually (yet steadily) increasing, such phenomenon directly reflects on labor market raising the need to create the optimal conditions for jobs which must be sustainable for the entire working life of an individual, while constantly ensuring good health and quality of life. In this context, prevention and management of low back disorders (LBDs) should be effective starting from the working environment. To this purpose, quantitative, reliable and accurate tools are needed to assess the main parameters associated to the biomechanical risk. In the last decade, the technology of wearable devices has made available several options that have been proven suitable to monitor the physical engagement of individuals while they perform manual or office working tasks. In particular, the use of miniaturized Inertial Measurement Units (IMUs) which has been already tested for ergonomic applications with encouraging results, could strongly facilitate the data collection process, being less time- and resources-consuming with respect to direct or video observations of the working tasks. Based on these considerations, this research intends to propose a simplified measurement setup based on the use of a single IMUs to assess trunk flexion exposure, during actual shifts, in occupations characterized by significant biomechanical risk. Here, it will be demonstrated that such approach is feasible to monitor large groups of workers at the same time and for a representative duration which can be extended, in principle, to the entire work shift without perceivable discomfort for the worker or alterations of the performed task. Obtained data, which is easy to interpret, can be effectively employed to provide feedback to workers thus improving their working techniques from the point of view of safety. They can also be useful to ergonomists or production engineers regarding potential risks associated with specific tasks, thus supporting decisions or allowing a better planning of actions needed to improve the interaction of the individual with the working environment

Towards understanding of climbing, tip-over prevention and self-righting behaviors in Hexapoda

Die vorliegende Dissertation mit dem Titel “Towards understanding of climbing, tip-over prevention and self-righting behaviors in Hexapoda” untersucht in drei Studien exemplarisch, wie (i) Wüstenameisen ihre Beine einsetzen um An- und Abstiege zu überwinden, wie (ii) Wüsten- und Waldameisen ein Umkippen an steilen Anstiegen vermeiden, und wie sich (iii) Madagaskar-Fauchschaben, Amerikanische Großschaben und Blaberus discoidalis Audinet-Servill, 1839 aus Rückenlagen drehen und aufrichten. Neuartige biomechanischen Beschreibungen umfassen unter anderem: Impuls- und Kraftwirkungen einzelner Ameisenbeine auf den Untergrund beim Bergauf- und Bergabklettern, Kippmomente bei kletternden Ameisen, Energiegebirge-Modelle (energy landscapes) zur Quantifizierung der Körperform für die funktionelle Beschreibung des Umdrehens aus der Rückenlage

Secret Signals from Another World: Walter Benjamin’s Concept of Innervation

Walter Benjamin refers to the “idea of revolution as an innervation of the technical organs of the collective” as one of the articles of his politics. The significance of this assertion has received relatively little attention in the philosophical reception of his political thought compared to the alternative model of revolution – made famous from the paralipomena to the late theses ‘On the Concept of History’ – as the emergency handbrake of history. Drawing on some of the debates and tensions generated by the work of Miriam Bratu Hansen, this discussion aims at an exegesis of some of the lesser known intellectual sources that influenced Benjamin’s theory of innervation. The purpose in doing so is not an attempt to reconcile or integrate these sources with dominant philosophical reconstructions of what is sometimes characterized as Benjamin’s “Western Marxism” and elaborated, in the more familiar context of Surrealist innervation, as a synthesis of Freud and Marx, but rather to reveal an alternative constellation of Soviet biomechanics and reactionary anti-capitalist Lebensphilosophie, united in their shared rejection of Freudian psychoanalysis

Computational Modelling of Cancer Systems: From Individual to Collective Cell Behaviour

Debido a su complejidad, el cáncer sigue siendo una de las principales causas de muerte a nivel mundial. La creación de prácticas preventivas adecuadas y terapias innovadoras está limitada por la falta de comprensión de los mecanismos básicos que causan el cáncer. Como tal, se deben desarrollar métodos nuevos y más efectivos que avancen nuestra comprensión del cáncer. En los últimos años, se ha visto un aumento en el uso de modelos computacionales para explicar procesos biológicos que son costosos y difíciles de explorar en entornos experimentales. Estos métodos permiten la traducción de mecanismos biológicos en ecuaciones y suposiciones matemáticas que pueden evaluarse utilizando herramientas informáticas para producir nuevas hipótesis. Además, las tecnologías computacionales se están volviendo más potentes debido a la disponibilidad de datos y la amplia capacidad de procesamiento.El objetivo global de esta tesis es diseñar e implementar modelos computacionales de cáncer, comenzando con comportamientos simples y aislados y progresando hacia fenómenos más complejos. Se abordan tres campos de investigación específicos para lograr este objetivo general: (i) motilidad unicelular, (ii) crecimiento tumoral y (iii) formación de patrones. En el primer objetivo, se presenta un modelo computacional para simular la motilidad celular individual que considera las propiedades mecánicas y químicas del microambiente. Posteriormente, este trabajo fue ampliado para tener en cuenta las interacciones célula-célula y reproducir el crecimiento de estructuras tumorales multicelulares. Por último, todos los eventos biológicos mencionados anteriormente fueron considerados y se añadió la diferenciación celular como el bloque de construcción final de esta tesis para simular la formación de patrones espaciales.Además, esta tesis analiza la relevancia de integrar datos experimentales y métodos computacionales para mejorar la precisión biológica y confirmar los resultados del modelo. En particular, muestra cómo se pueden usar técnicas de calibración y optimización para considerar datos empíricos en el diseño y validación de modelos. Los resultados experimentales cualitativos y cuantitativos, tanto de la literatura como de nuevos experimentos, se reproducen en este artículo para mostrar diferentes enfoques en la integración de datos.En general, esta tesis proporciona un modelo de cómo se pueden utilizar los métodos computacionales para analizar y comprender problemas complejos en la biología del cáncer.Demuestra explícitamente cómo los componentes del modelo pueden representar ciertos aspectos de la biología del cáncer, que pueden mejorarse y reproducirse utilizando datos experimentales. En consecuencia, los comportamientos complejos, como el crecimiento tumoral y la formación de patrones, resultan de la intrincada interacción entre los componentes del modelo.<br /

Aerospace Medicine and Biology: A continuing bibliography with indexes, supplement 237

A bibliography is given on the biological, physiological, psychological, and environmental effects to which man is subjected during and following simulated or actual flight in the Earth's atmosphere or in interplanetary space. References describing similar effects of biological organisms of lower order are also included. Such related topics as sanitary problems, pharmacology, toxicology, safety and survival, life support systems, exobiology, and personnel factors receive appropriate attention. In general, emphasis is placed on applied research, but references to fundamental studies and theoretical principles related to experimental development also qualify for inclusion