This thesis explores the field of robotic hand exoskeletons and their applications. These systems have emerged in popularity over the years, due to their potentials to advance the medical field as assistive and rehabilitation devices, and the field of virtual reality as haptic gloves. Although much progress has been made, hand exoskeletons are faced with several design challenges that are hard to overcome without having some tradeoffs. These challenges include: (1) the size and weight of the system, which can affect both the comfort of wearing it and its portability, (2) the ability to impose natural joint angle relationships among the user's fingers and thumb during grasping motions, (3) safety in terms of limiting the range of motions produce by the system to that of the natural human hand and ensuring the mechanical design does not cause harm or injury to the user during usage, (4) designing a device that is user friendly to use, and (5) the ability to effectively perform grasping motions and provide sensory feedback for the system to be applicable in various application fields. In order to address these common issues of today's state-of-the-art hand exoskeleton systems, this thesis proposes a mechanism design for a novel hand exoskeleton and presents the integration of several prototypes. The proposed hand exoskeleton is designed to assist the user with grasping motions while maintaining a natural coupling relationship among the finger and thumb joints to resemble that of a normal human hand. The mechanism offers the advantage of being small-size and lightweight, making it ideal for prolong usage. Several applications are discussed to highlight the proposed hand exoskeleton functionalities in processing sensory information, such as position and interactive forces. / MS

Activities of daily living (ADL) such as writing, eating, and object manipulation are challenging for patients suffering from pathological tremors. Pathological tremors are involuntary, rhythmic, and oscillatory movements that manifest in limbs, the head, and other body parts. Among the existing treatments, mechanical loading through wearable rehabilitation devices is popular for being non-invasive and innocuous to the human body. In particular, a few exoskeletons are developed to actively mitigate pathological tremors in the forearm. While these forearm exoskeletons can effectively suppress tremors, they still require significant improvements in ergonomics to be implemented for ADL applications. The ergonomics of the exoskeleton can be improved via design and motion control pertaining to human biomechanics, which leads to better efficiency, comfort, and safety for the user. The wrist is a complicated biomechanical joint with two coupled degrees of freedom (DOF) pivotal to human manipulation capabilities. Existing exoskeletons either do not provide tremor suppression in all wrist DOFs, or can be restrictive to the natural wrist movement. This motivates us to explore a better exoskeleton solution for wrist tremor suppression. We propose TAWE - a wearable exoskeleton that provides alleviation of pathological tremors in all wrist DOFs. The design adopts a 6-DOF rigid linkage mechanism to ensure unconstrained natural wrist movements, and wearability features without extreme tight-binding or precise positioning for convenient ADL applications. When TAWE is equipped by the user, a closed-kinematic chain is formed between the exoskeleton and the forearm. We analyze the coupled multibody dynamics of the human-exoskeleton system, which reveals a few robotic control problems - (i) The first problem is the identification of the unknown wrist kinematics within the closed kinematic chain. We realize the real-time wrist kinematic identification (WKI) based on a novel ellipsoidal joint model that describes the coupled wrist kinematics, and a sparsity-promoting Extended Kalman Filter for the efficient real-time regression; (ii) The second problem is the exoskeleton motion control for tremor suppression. We design a robust adaptive controller (IO-RAC) based on model reference adaptive control and inverse optimal robust control theories, which can identify the unknown model inertia and load, and provide stable tracking control under disturbance; (iii) The third problem is the estimation of voluntary movement from tremorous motion data for the motion planning of exoskeleton. We develop a lightweight and data-driven voluntary movement estimator (SVR-VME) based on least square support vector regression, which can estimate voluntary movements with real-time signal adaptability and significantly reduced time delay. Simulations and experiments are carried out to test the individual performance of robotic control algorithms proposed in this study, and their combined real-time performance when integrated into the full exoskeleton control system. We also manufacture the prototype of TAWE, which helps us validate the proposed solutions in tremor alleviation exoskeletons. Overall, the design of TAWE meets the expectations in its compliance with natural wrist movement and simple wearability. The exoskeleton control system can execute stably in real-time, identify unknown system kinematics and dynamics, estimate voluntary movements, and suppress tremors in the wrist. The results also indicate a few limitations in the current approaches, which require further investigations and improvements. Finally, the proposed exoskeleton control solutions are developed based on generic formulations, which can be applied to not only TAWE, but also other rehabilitation exoskeletons. / Doctor of Philosophy / Activities of daily living (ADL) such as writing, eating, and object manipulation are challenging for patients suffering from pathological tremors, which affect millions of people worldwide. Tremors are involuntary, rhythmic, and oscillatory movements. In recent years, rehabilitation exoskeletons are developed as non-invasive solutions to pathological tremor alleviation. The wrist is pivotal to human manipulation capabilities. Existing exoskeletons either do not provide tremor suppression in all wrist movements, or can be restrictive to natural wrist movements. To explore a better solution with improved performance and ergonomics, we propose TAWE - a wearable exoskeleton that provides tremor alleviation in full wrist motions. TAWE adopts a high-degree-of-freedom mechanism to ensure unconstrained natural wrist movements, and wearability features for convenient ADL applications. The coupled dynamics between the forearm and TAWE leads to a few robotic control problems. We propose novel real-time robotic control solutions in the identification of unknown wrist kinematics, robust adaptive exoskeleton control for tremor suppression, and voluntary movement estimation for motion planning. Later, simulations and experiments validate the TAWE prototype and its exoskeleton control framework for tremor alleviation, and reveal limitations in the current approaches that require further investigations and improvements. Finally, the proposed exoskeleton control solutions are developed based on generic formulations, which can be applied to not only TAWE, but also other rehabilitation exoskeletons.

Robotic rehabilitation and assessment of the human upper-limb following stroke is currently limited in part by the inability of robots to replicate natural motion. In particular, motion of the shoulder girdle is usually neglected, despite the fact that the shoulder girdle is necessary to stabilize and orient the upper-limb during activities of daily living. Without direct control of the shoulder girdle, it is not possible to monitor or prevent a patient from making compensatory movements, which inhibits functional recovery, nor is there a means to properly regain strength and coordination. The more the robot is able to realistically mimic upper-limb motion, the more able the robot will be to assist with true functional movement training, which gives the patient the best chance of motor recovery. To address this issue, a new adjustable robotic exoskeleton called MEDARM is proposed for rehabilitation and assessment of the shoulder complex. MEDARM provides independent control of six degrees of freedom of the upper-limb: two at the sternoclavicular joint, three at the glenohumeral joint and one at the elbow. A key design feature of the new robot is an innovative curved track mechanism actuated by a cable-drive transmission system. To facilitate a performance evaluation of this new mechanism, a planar version of MEDARM was designed. A full prototype of this planar robot was constructed and several fundamental metrics, including friction, inertia, and compliance, were used to test its mechanical performance. Additionally, the functionality of the robot was examined using preliminary data recorded during a standard reaching task, and by implementing some basic rehabilitation algorithms. This thesis describes the design of MEDARM and its planar counterpart in detail and the performance evaluation of the prototype is presented. / Thesis (Ph.D, Electrical & Computer Engineering) -- Queen's University, 2008-08-13 21:19:14.335

Many occupations require workers to perform repetitive tasks such as lifting and bending that put significant strain on their bodies resulting in high levels of injury. Exoskeletons are one method of being able to decrease the forces on a worker while still allowing them to move. In this research, I propose a novel exoskeleton design that integrates the design process with an ethical understanding of how technology is used in society and a potential plan for an interdisciplinary approach to better adoption of this type of assistive technology. The exoskeleton is based around a novel differential that allows the exoskeleton legs to articulate during ambulatory motion while providing automatic lifting engagement by linking the force-generating mechanisms in each leg. Using a differential also allows the integration of a custom support level that can be changed during the design to better fit the varying motions found in different professions such as farming and manufacturing. Testing for this design was performed by using farming-related tasks in a laboratory to understand the level of support provided by the exoskeleton. Results show the exoskeleton provides significant support for these tasks. This validation helps build trust in the technology before it is tested on actual farmers in real-world situations and helps minimize ethical concerns regarding potential exoskeleton use. I also discuss the ethical concerns and how they can be mitigated during the design and implementation phases to ensure workers are protected and improve overall buy-in to exoskeleton technology in the workplace. / Doctor of Philosophy / Many jobs require workers to perform tasks that put their bodies at risk of injuries such as repetitive lifting and bending. Exoskeletons, devices you can wear on your body to help you lift, are one solution to help workers do their jobs better and with less risk of getting injured. In this research I propose a new type of exoskeleton that supports the back; designed, built, and tested it; and present much additional discussion about how people think and feel about exoskeletons and how society can ethically use them. The exoskeleton uses a new system that connects both legs to make it easier to go from walking to lifting, making it feel more natural and requiring less input from the user. With this design, we can also customize the lifting help for different jobs by switching out a component on the exoskeleton. This makes the exoskeleton customizable for the types of movement in different jobs like farming and manufacturing. Several farming tasks were then tested in a laboratory setting with the exoskeleton and showed it decreases the energy needed for the different tasks. Doing this testing also helps build trust with communities who might want to use the exoskeleton but are skeptical of new technology. Taking this approach and making the design adjustable is one step to helping to make this technology ethical when it is adopted by individuals or companies. Ethical considerations for exoskeletons are also new and not well discussed so I provide a framework to help make ethical decisions for adopting exoskeletons.

There is a small but growing population of people who suffer from impaired balance. The causes range from old age to stroke to cerebral palsy. For those with only minor problems staying upright, a cane or walker is all that is needed. For some it is so debilitating that they are confined to a wheel chair. The precise cause of impairment can vary. In some, the vestibular, proprioceptive or visual impairments affect balance. In others, muscle weakness or brain damage is the cause. In another group, the brain never learned to balance in the first place. Relearning how to balance can be a struggle requiring months of costly physical therapy with a physical therapist. A machine that could help teach them how to balance would be a great help in the improvement of their lives. This thesis presents a set of control models for an exoskeleton that will stabilize and restore stability to those with impaired balance. The control models are designed for an exoskeleton to initially force the wearer into a known profile for balancing and moving. There will then be a steady reduction in the authority of the exoskeleton over time, requiring the patient to assert more control over his or her own movement. As the authority of the exoskeleton is reduced, the patient will have to increase his or her own authority and develop his or her own control law or the patient will become less stable and eventually unbalanced. We expect this treatment method will increase the stability of patients, allowing them to steadily adapt to standing and walking. This will then allow them mobility without the use of a wheel chair and decrease their risk of falling. Further, the use of this device will enable the patients to receive therapy at home and in their normal life without the need to visit a physical therapist for rehabilitation, enabling the patients to receive therapy at home and for a longer period of time than they currently do. / Master of Science

This dissertation focuses on improving the capabilities of an assistive robotic exoskeleton glove designed for patients with Brachial Plexus Injuries (BPI). The aim of this research is to develop a force control method, an automatic force planning method, and a Human-Machine Interface (HMI) to refine the grasping functionalities of the exoskeleton glove, thus helping rehabilitation and independent living for individuals with BPI. The exoskeleton glove is a useful tool in post-surgery therapy for patients with BPI, as it helps counteract hand muscle atrophy by allowing controlled and assisted hand movements. This study introduces an assistive exoskeleton glove with rigid side-mounted linkages driven by Series Elastic Actuators (SEAs) to perform five different types of grasps. In the aspect of force control, data-driven SEA fingertip force prediction methods were developed to assist force control with the Linear Series Elastic Actuators (LSEAs). This data-driven force prediction method can provide precise prediction of SEA fingertip force taking into account the deformation and friction force on the exoskeleton glove. In the aspect of force planning, a slip-grasp force planning method with hybrid slip detection is implemented. This method incorporates a vision-based approach to estimate object properties to refine grasp force predictions, thus mimicking human grasping processes and reducing the trial-and-error iterations required for the slip- grasp method, increasing the grasp success rate from 71.9% to 87.5%. In terms of HMI, the Configurable Voice Activation and Speaker Verification (CVASV) system was developed to control the proposed exoskeleton glove, which was then complemented by an innovative one-shot learning-based alternative, which proved to be more effective than CVASV in terms of training time and connectivity requirements. Clinical trials were conducted successfully in patients with BPI, demonstrating the effectiveness of the exoskeleton glove. / Doctor of Philosophy / This dissertation focuses on improving the capabilities of a robotic exoskeleton glove designed to assist individuals with Brachial Plexus Injuries (BPI). The goal is to enhance the glove's ability to grasp and manipulate objects, which can help in the recovery process and enable patients with BPI to live more independently. The exoskeleton glove is a tool for patients with BPI to used after surgery to prevent the muscles of the hand from weakening due to lack of use. This research introduces an exoskeleton glove that utilizes special mechanisms to perform various types of grasp. The study has three main components. First, it focuses on ensuring that the glove can accurately control its grip strength. This is achieved through a special method that takes into account factors such as how the materials in the glove change when it moves and the amount of friction present. Second, the study works on a method for planning how much force the glove should use to hold objects without letting them slip. This method combines a camera-based object and material detection to estimate the weight and size of the target object, making the glove better at holding things without dropping them. The third part involves designing how people can instruct the glove what to do. The command can be sent to the robot by voice. This study proposed a new method that quickly learns how you talk and recognizes your voice. The exoskeleton glove was tested on patients with BPI and the results showed that it is successful in helping them. This study enhances assistive technology, especially in the field of assistive exoskeleton glove, making it more effective and beneficial for individuals with hand disabilities.

This thesis presents the development and experimental testing of a lower-limb exoskeleton system. The device supplies assistive torque at the knee joint to alleviate the loading at the knee, and thus reduce the muscular effort required to perform activities of daily living. The hypothesis is that the added torque would facilitate the execution of these movements by people who previously had limited mobility. Only four specific movements were studied: level-waking, gradient-walking, sit-to-stand-to-sit and ascending stairs. All three major components of the exoskeleton system, i.e. the exoskeleton actuators and actuator control system, the user intention estimation algorithm, and the mechanical construction of the exoskeleton, were investigated in this work. A leg brace was fabricated in accordance with the biomechanics of the human lower-limb. A single rotational degree of freedom at the knee and ankle joints was placed to ensure that the exoskeleton had a high kinematic compliance with the human leg. The position of the pneumatic actuators and sensors were also determined after significant deliberation. The construction of the device allowed the real-world testing of the actuator control algorithm and the user intention estimation algorithms. Pneumatic artificial muscle actuators, that have high power to weight ratio, were utilized on the exoskeleton. An adaptive fuzzy control algorithm was developed to compensate for the inherent nonlinearities in the pneumatic actuators. Experimental results confirmed the effectiveness of the adaptive controller. The user intention estimation algorithm is responsible for interpreting the user's intended movements by estimating the magnitude of the torque exerted at the knee joint. To accomplish this, the algorithm utilizes biological signals that emanate from the knee extensor and flexor muscles when they are activated. These signals combined with the knee angle data are used as inputs to the estimation algorithm. The output is the magnitude and direction of the estimated torque. This value is then scaled by an assistance ratio, which determines the intensity of the assistive torque provided to the user. The experiments conducted verify the robustness and predictability of the proposed algorithms. Finally, experimental results from the four activities of daily living, affirm that the desired movements could be performed successfully in cooperation with the exoskeleton. Furthermore, muscle activity recorded during the movements show a reduction in effort when assisted by the exoskeleton.

Pesquisas sobre próteses ativas e exoesqueletos têm se intensificado nas últimas décadas. Seu uso para reabilitação, aumento de força ou substituição de um membro debilitado já está sendo utilizado comercialmente. Porém, um dos desafios para o controle deste tipo de dispositivo é a identificação dos parâmetros das articulações humanas para que o equipamento simule o mesmo comportamento e a interface homem máquina seja mais eficaz e confortável. Este trabalho apresenta o desenvolvimento, construção e validação de um exoesqueleto que é um dispositivo para estudo da marcha. Em outras palavras, o exoesqueleto apresentado é capaz de medir a força de interação com o corpo humano bem como a posição angular das articulações do joelho e tornozelo durante a marcha. Com essas medições é possível calcular os parâmetros de impedâncias dessas articulações. A revisão bibliográfica sobre exoesqueletos foi necessária para a definição dos requisitos do projeto. O projeto do exoesqueleto desenvolvido pela autora durante o trabalho de conclusão de curso foi revisto de acordo com os requisitos estabelecidos. Assim, o novo projeto, chamado de Protótipo II ou ExoLoLi, é capaz de suprir as deficiências do primeiro projeto e atender a todos os requisitos para ser uma ferramenta de estudo da marcha. O ExoLoLi foi construído e experimentos preliminares foram realizados para a sua validação como ferramenta de estudo da marcha. Foi possível confirmar que o exoesqueleto faz as medições de força de interação e de posição corretamente. Também foi possível verificar que o exoesqueleto interfere no padrão natural da marcha. De qualquer forma, o exoesqueleto poderá ser usado, não apenas para o cálculo dos parâmetros de impedância, mas também para estudo de consumo energético com diferentes tipos de controle e para diferentes aplicações (como reabilitação e aumento de força), dependendo do controle programado para o seu funcionamento. / Research on active prosthetics and exoskeletons has been intensified in recent decades. Its use for rehabilitation, strength increase or replacement of a disabled member is already being used commercially. But one of the challenges for the control of this type of device is the identification of the human joint\'s parameters so the machine is able to simulate the same behavior and the man-machine interface is more effective and comfortable. This dissertation presents the development, construction and validation of an exoskeleton which is a device for gait study. In other words, the presented exoskeleton is capable of measuring the interaction force with the human body as well as the angular position of the knee and ankle joints during gait. With these measurements it is possible to calculate the impedance parameters of these joints. The literature review about exoskeletons was necessary to define the project requirements. The exoskeleton developed by the author to obtain the engineering degree (undergraduate paper) has been reviewed in accordance with the established requirements. So the new exoskeleton design, called as Prototype II or ExoLoLi, is able to address the weaknesses of the first project and meet all the requirements to be a gait study tool. The ExoLoLi was built and preliminary experiments were performed to validate it as gait study tool. It was confirmed that the exoskeleton is able to measure the interaction forces and the angular position correctly. It was also observed that the exoskeleton interferes at the natural gait pattern. Anyway, the exoskeleton can be used not only for calculating the human impedance parameters, but also to analyze the energy consumption using different control strategies and to be used in different applications (such as rehabilitation or strength increase) depending on the programmed control for its operation.

A família Bougainvilliidae é um grupo de hidrozoários \"Anthoathecata\" \"Filifera\" pouco conhecido. Nesse estudo, diversos aspectos da biologia do grupo e de táxons relacionados a ele foram analisados e discutidos. Nossas análises incluem: uma revisão bibliográfica dos táxons de Bougainvilliidae, a partir de um embasamento histórico e geográfico sobre seu conhecimento atual; uma síntese sobre sua estrutura exoesquelética, abrangendo informações de outros medusozoários fósseis e atuais; análises histológicas e microestruturais de pólipos de diversos grupos de Medusozoa; e um estudo integrado da evolução de Bougainvilliidae, considerando-se dados moleculares e morfológicos. Os resultados desvendaram gêneros e espécies válidos, padrões possíveis de distribuição latitudinal para pólipos e medusas de Bougainvilliidae, assim como a universalidade e evolução do exoesqueleto como fonte de informação para compreender padrões de diversificação dentro de Bougainvilliidae e em relação a outros Medusozoa. Além disso, os resultados evidenciam a variação na síntese, estrutura e função do exoesqueleto dentre os medusozoários, apontando que a esqueletogênese retrocede ao Ediacarano, sendo que o exoesqueleto axial córneo (complexo quitina-proteico) predomina nos pólipos atuais e atua como uma estrutura de suporte e proteção, entre outras funções. O exoesqueleto apresenta maior variação e complexidade estrutural entre os pólipos de Hydroidolina, grupo para o qual foi descrito um novo tipo de exoesqueleto bicamada, que é encontrado na maioria dos Bougainvilliidae. Resultados das análises filogenéticas identificam a \"Bougainvilliidae\" e \"Bougainvillia\" como táxons não-monofiléticos, e demonstram que o grupo monofilético Pseudothecata taxon novum inclui os gêneros classicamente assumidos em \"Bougainvilliidae\" (exceto Dicoryne), entre outras famílias de \"Anthoathecata\". Neste estudo, ampliamos o nosso entendimento sobre a natureza química e física do exoesqueleto em Medusozoa, estrutura com um valor subestimado na taxonomia do grupo. Concluímos que estudar a \"síntese molecular\", \"matriz molecular\" e \"expressão morfológica\" do exoesqueleto é essencial para inferências evolutivas e ecológicas, as quais podem ser intrinsecamente correlacionadas com outras áreas biológicas, tais como biologia de conservação e filogeografia / The family Bougainvillidae is a poorly known group of hydrozoans \"Anthoathecata\" \"Filifera\". In this study, several aspects of the biology of this group and other related taxa are analyzed and discussed. Our analyzes include: a bibliographic revision of the taxa comprising the Bougainvilliidae, based on its current historical and geographical knowledge; a synthesis regarding its exoskeletal structure, including information on other extinct and extant medusozoans; histological and microstructural analyzes of polyps of several groups of Medusozoa; and an integrated study on the evolution of the Bougainvilliidae, considering molecular and morphological data. The results validated several genera and species and possible latitudinal distributional patterns for polyps and medusae of Bougainvilliidae, as well as the universality and evolution of the exoskeleton as a source of information to understand its role in the diversification patterns in Bougainvilliidae and with relation to other Medusozoa. Additionally, the results reveal the existence of variation on the synthesis, structure and function of the exoskeleton among the Medusozoa, showing that the exoskeletogenesis dates back to the Ediacaran, since the corneus exoskeleton (chitin-protein complex) predominates today in current polyps and acts as a supporting structure and protection, among other functions. The skeleton has higher variation and structural complexity among polyps of Hydroidolina, taxon from which we described a new type of bilayer exoskeleton, which is found in most of the species of Bougainvilliidae. Results of phylogenetic analyzes identificate \"Bougainvilliidae\" and \"Bougainvillia\" as non-monophyletic taxa, and showed that the monophyletic group Pseudothecata taxon novum includes the classical genera usually inserted in the \"Bougainvilliidae\" (excluding Dicoryne), and other families of \"Anthoathecata\". In this study, we increased our understanding of the chemical and physical nature of the exoeskeleton of Medusozoa, a structure whith an underestimate role in the taxonomy of the group. We concluded that the study of the \"molecular synthesis\", the \"molecular matrix\" and the \"morphological expression\" of the exoskeleton is necessary for evolutionary and ecological inferences, which are intrinsically related to other biological areas, such as conservation biology and phylogeography

The external skeletons, Exoskeletons, are not a new research area in this highly developed world. They are widely used in helping the wearer to enhance human strength, endurance, and speed while walking with them. Most exoskeletons are designed for the whole body and are powered due to their applications and high performance needs. This thesis introduces a novel design of a three-degree of freedom parallel robotic structured hip exoskeleton, which is quite different from these existing exoskeletons. An exoskeleton unit for walking typically is designed as a serial mechanism which is used for the entire leg or entire body. This thesis presents a design as a partial manipulator which is only for the hip. This has better advantages when it comes to marketing the product, these include: light weight, easy to wear, and low cost. Furthermore, most exoskeletons are designed for lower body are serial manipulators, which have large workspace because of their own volume and occupied space. This design introduced in this thesis is a parallel mechanism, which is more stable, stronger and more accurate. These advantages benefit the wearers who choose this product. This thesis focused on the analysis of the structure of this design, and verifies if the design has a reasonable and reliable structure. Therefore, a series of analysis has been done to support it. The mobility analysis and inverse kinematic solution are derived, and the Jacobian matrix was derived analytically. Performance of the CAD model has been checked by the finite element analysis in Ansys, which is based on applied force and moment. The comparison of the results from tests has been illustrated clearly for stability iii and practicability of this design. At the end of this thesis, an optimization of the hip exoskeleton is provided, which offers better structure of this design. / UOIT