A novel hip exoskeleton with six degrees of freedom (DoF) was developed, and multiple prototypes of this product were created in this thesis. The device was an upper level of the 12-DoF lower-body exoskeleton project, which was known as the Orthotic Lower-body Locomotion Exoskeleton (OLL-E). The hip exoskeleton had three motions per leg, which were roll, yaw, and pitch. Currently, the sufferers of hemiplegia and paraplegia can be addressed by using a wheelchair or operating an exoskeleton with aids for balancing. The motivation of the exoskeleton project was to allow paraplegic patients to walk without using aids such as a walker or crutches. In mechanical design, the hip exoskeleton was developed to mimic the behavior of a healthy person closely. The hip exoskeleton will be fully powered by a custom linear actuator for each joint. To date, there are no exoskeleton products that are designed to have all of the hip joints powered. Thus, packaging of actuators was also involved in the mechanical design of the hip exoskeleton. As a result, the output torque and speed for the roll joint and yaw joint were calculated. Each hip joint was structurally designed with properly selected bearings, encoder, and hard stops. Their range of motions met desired requirements. In addition, a backpack assembly was designed for mounting the hardware, such as cooling pumps, radiators, and batteries. In the verification part, finite element analysis (FEA) was conducted to show the robustness of the structural design. For fit testing, three wearable prototypes were produced to verify design choices. As a result, the weight of the current hip exoskeleton was measured as 32.1 kg. / Master of Science

Embedded systems for humanoid robots are required to be reliable, low in cost, scalable and robust. Most of the applications related to humanoid robots require efficient force control of Series Elastic Actuators (SEA). These control loops often introduce precise timing requirements due to the safety critical nature of the underlying hardware. Also the motor controller needs to run fast and interface with several sensors. The commercially available motor controllers generally do not satisfy all the requirements of speed, reliability, ease of use and small size. This work presents a custom motor controller, which can be used for real time force control of SEA on humanoid robots and exoskeletons. Emphasis has been laid on designing a system which is scalable, easy to use and robust. The hardware and software architecture for control has been presented along with the results obtained on a novel Series Elastic Actuator based humanoid robot THOR. / Master of Science

This thesis explores the field of hand exoskeleton robotic systems with slip detection and its applications. It presents the design and control of the intelligent sensing and force- feedback exoskeleton robotic (iSAFER) glove to create a system capable of intelligent object grasping initiated by detection of the user’s intentions through motion amplification. Using a combination of sensory feedback streams from the glove, the system has the ability to identify and prevent object slippage, as well as adapting grip geometry to the object properties. The slip detection algorithm provides updated inputs to the force controller to prevent an object from being dropped, while only requiring minimal input from a user who may have varying degrees of functionality in their injured hand. This thesis proposes the use of a high dynamic range, low cost conductive elastomer sensor coupled with a negative force derivative trigger that can be leveraged in order to create a controller that can intelligently respond to slip conditions through state machine architecture, and improve the grasping robustness of the exoskeleton. The mechanical and electrical improvements to the previous design, the sensing and force- feedback exoskeleton robotic (SAFER) glove, are described while details of the controller design and the proposed assistive and rehabilitative applications are explained. Experimental results confirming the validity of the proposed system are also presented. In closing, this thesis concludes with topics for future exploration. / Master of Science / Exoskeletons are robotic systems that have rigid external covering, such as links, joints, and/or soft artificial tendons or muscles, for the desired body part to provide support and/or protection. These are typically used to enhance power and strength, provide rehabilitation and assistance, and teleoperate other robots from a distance. While the US Army developed exoskeletons for strengthening purposes, another potential purpose of exoskeletons, which is serving medical needs, such as rehabilitation, attracted a lot of attention. Among numerous illnesses and injuries that may lead to impaired hand functionality, the U.S. Department of Health and Human Services estimated that approximately 470,000 people survive strokes every year in the United States and require continuous rehabilitation to recover their motor functions. Though medical professionals believe that the intensity and duration of rehabilitation is the key for maximizing the rate of recovery, it is often limited due to many reasons, such as cost or difficulty in attending rehabilitation sessions. To augment the availability and quality of rehabilitation, the study of exoskeletons has earned popularity. Beyond the capability of providing simple movements, such as passive rehabilitation, many scientists researched to provide active rehabilitation, which involves active participation from the patients. Furthermore, detecting the patient’s intention to activate the rehabilitation glove became a topic of interest, and many types of sensors were utilized in research. This thesis explores the design and control of the intelligent sensing and force- feedback exoskeleton robotic (iSAFER) glove, which detects the user’s intentions to activate the system through motion amplification. The iSAFER glove performs soft initial grasp until the fingers touch an object. After the object is gently grabbed and lifted, the grasp is autonomously adjusted through slip detection until there is no more slip. To facilitate this idea, a low cost force sensor was created and leveraged to improve the grasping control of the exoskeleton. The mechanical and electrical improvements to the previous design, the sensing and force-feedback exoskeleton robotic (SAFER) glove, are described while details of the controller design and the proposed assistive and rehabilitative applications are explained. Experimental results confirming the validity of the proposed system are also presented. In closing, this thesis concludes with topics for future exploration.

In this study, structure-property relationships in the ironclad beetle (Zopherus nodulosus haldemani) exoskeleton are quantified to develop novel bio-inspired impact resistance technologies. The hierarchical structure of this exoskeleton was observed at various length scales for both the ironclad beetle pronotum and elytron. The exocuticle and endocuticle layers provide the bulk of the structural integrity and consist of chitiniber planes arranged in a Bouligand structure. The pronotum consists of a layered structure, while elytron consists of an extra layer with “tunnel-like” voids running along the anteroposterior axis along with smaller interconnecting “tunnel-like” voids in the lateral plane. Energy dispersive X-ray diffraction revealed the existence of minerals such as calcium carbonate, iron oxide, zinc oxide, and manganese oxide. We assert that the strength of this exoskeleton could be attributed to its overall thickness, the epicuticle layer thickness, the existence of various minerals embedded in the exoskeleton, and its structural hierarchy. The thickness of the exoskeleton correlates to a higher number of chitiniber planes to increase fracture toughness, while the increased thickness of the epicuticle prevents hydration of the chitiniber planes. In previous studies, the existence of minerals in the exoskeleton has been shown to create a tougher material compared to non-mineralized exoskeletons.

No description available.

There is emerging evidence for the potential of occupational back-support exoskeletons (BSEs) to reduce physical demands, and thereby help control/prevent the risk of overexertion injuries associated with manual material handling. However, it is important to understand whether BSEs also introduce any unintended safety challenges. One potential risk associated with BSE use is increased risk of falls, since their extra weight, rigid structure, and external hip extension torque may increase demands on the postural control system. However, there is currently limited evidence on whether, and to what extent, BSE use alters postural stability and/or fall risk. The primary goal of this work was to understand the effects of exoskeleton use, and quantify the effects of exoskeleton design parameters, on balance and postural stability, with a focus on passive BSEs used for repetitive lifting work. A comprehensive evaluation of BSE use was performed under controlled laboratory conditions, focusing on three classes of human activity that form the basis of maintaining postural balance in diverse real-life scenarios: maintenance of a specified posture, voluntary movement, and reaction to an external perturbation. The first study demonstrated that during quiet bipedal stance, BSE use increased median frequency and velocity of the center of pressure in the anterior-posterior direction. In the second study on level walking, BSE use caused an increase in gait step width and gait variability, and decrease in the margin of stability. BSE use with high supportive torque led to adapted gait patterns in early-stance phase. Hip range of motion and peak hip flexion velocity also decreased, and participants exhibited different strategies to increase mechanical energy for propelling the leg in late-stance phase: these effects increased with increasing torque applied by the exoskeleton. In the final study, BSE use did not alter the maximal lean angle from which individuals could successfully execute single step balance recovery, following a forward loss of balance. However, several recovery responses were negatively affected by BSE use, including increased reaction time, impeded hip flexion, and reduced margin of stability in the high-torque condition. This is the first systematical investigation to quantify the effects of passive BSEs with multiple supportive torque levels on balance and postural stability. While exoskeleton effects on static balance were minimal, more substantial changes in gait spatiotemporal parameters, hip joint kinematics, and dynamic margins of stability were observed in the later studies. Our results indicate that postural stability deteriorated with exoskeleton use in dynamic conditions, and provide mechanistic insight into how stability is altered by different exoskeleton design factors such as added mass, restricted range of motion, and external hip extension torque. While our results are suggestive of increased fall risk, especially in the high-torque condition, fall risk in real life is moderated by a complex combination of individual and environmental conditions. Future work should consider more complex, realistic tasks and also include a more diverse sample that is studied under longer exposure durations, to further elucidate these findings. Our characterizations of a wide variety of postural responses as a function of exoskeleton torque settings are expected to contribute to improving both design and practice guidelines to facilitate the safe adoption of BSEs in the workplace. / Doctor of Philosophy / Occupational back-support exoskeletons (BSEs) – wearable mechanical systems designed to support, augment, and/or assist back extension – are expected to serve as an alternative workplace intervention to control and prevent overexertion injuries related to manual material handling tasks. While recent studies have shown the beneficial effects of BSE use in terms of physical load reduction on the low back, some concerns have also been raised on unexpected or unintended effects of exoskeletons. One potential risk associated with exoskeleton use is increased risk of falls, since a BSE's extra weight, rigid structure, and external hip extension torque are expected to place increased demands on the postural control system. Increase in fall risk is a critical safety concern, as occupational falls are a serious problem in terms of injuries, medical/industrial cost, and lost work time. However, there exists limited evidence on whether the use of a BSE alters postural stability and/or increases fall risk. Hence, the goal of our study was to quantify the effects of BSE use on postural stability in various conditions related to real-life scenarios, such as standing balance, walking stability and how one would respond to a loss of balance following an external perturbation. Our results showed that during quiet standing, BSE use slightly increased postural sway. In level walking tasks, BSE use had adverse effects on step length, step width, and dynamic stability. Furthermore, wearing a BSE with high supportive torque led to adapted gait patterns in early-stance phase, whereas participants showed different strategies to increase mechanical energy for propelling the leg in late-stance phase. In the final study investigating single step balance recovery following a forward loss of balance, we found that BSE use negatively affects balance recovery, mainly by impeding hip flexion. Thus, our work suggests that exoskeleton use can deteriorate balance and/or postural stability in situations of static standing, voluntary walking, and reacting to an external perturbation, thereby potentially leading to an increase in fall risk. These effects may be more pronounced among specific population sub-groups such as older workers, and may also affect individuals more severely under conditions of stress or fatigue. Hence, future studies must include more rigorous testing of BSE use using a variety of challenging and realistic scenarios, and also include more diverse population samples. The findings from this work are expected to contribute to improving design and practice guidelines to facilitate the safe adoption of BSEs in the workplace.

The need for mechanisms that assist human movements has been increasing due to the rising number of people that has some kind of movement disability. In this scenario, it is of great importance the development of control methods that assist the interface between a motor assistive device and its user. This work proposes a controller for an exoskeleton with one degree of freedom, using surface electromyography signals from the user as the input signal. An exoskeleton was adapted to serve as platform for the developed control method. To create an EMG-to-Angle model, a set of experiments were carried out with six subjects. The experiment consisted of a series of continuous and discrete elbow flexion and extension movements with different load levels. Using the experimental data, linear (ARIMAX) and non linear (Hammerstein-Wiener) system identification methods were evaluated to determine which is the best candidate for the estimation of the EMG-to-Angle model, based on its accuracy and ease of implementation. A new experiment wasconducted to develop a real-time controller, based on FIR model and tested in a real-timeapplication. Tests showed that the controller is capable of estimating the elbow joint angle with correlation above 70% and root-mean-square error below 25° when compared to the measured elbow joint angles. / A necessidade por mecanismos que auxiliam os movimentos do ser humano vem crescendo devido ao aumento do número de pessoas portadores de deficiências que afetam a capacidade motora. Nesse cenário, é de grande importância o desenvolvimento de métodos de controle que auxiliem a interface entre o dispositivo de assistência motora e o seu usuário. Esse trabalho propõe um controlador para um exoesqueleto com um grau de liberdade, usando sinais de eletromiografia de superfície do usuário como sinal de entrada. Um exoesqueleto foi adaptado para servir de plataforma para o método de controle desenvolvido. Para criar um modelo EMG-ângulo, um conjunto de experimentos foi conduzido com seis voluntários. O experimento consistiu em uma série de movimentos de flexo-extensão do cotovelo contínuos e discretos com diferentes níveis de carga. Utilizando os dados do experimento, métodos de identificação de sistemas linear (ARIMAX) e não linear (Hammerstein-Wiener) foram avaliados para determinar qual o melhor candidato para a estimação do modelo EMG-ângulo, baseado em sua acurácia e facilidade de implementação. Um novo experimento foi conduzido para desenvolver um controlador em tempo real, baseado no modelo FIR e testado em uma aplicação em tempo real. Testes indicaram que o controlador é capaz de estimar o ângulo da junta do cotovelo com valores de correlação acima de 70% e raiz do erro quadrático médio menor que 25º, quando comparados aos valores medidos de ângulo da junta do cotovelo.

Esta dissertação apresenta o projeto e a construção de atuadores elásticos em série para o acionamento das juntas de um exoesqueleto para membros inferiores, baseado em uma órtese comercial. Inicialmente, considerou-se como dispositivo de testes a parte do exoesqueleto referente à junta do tornozelo, ou seja, a construção de uma órtese tornozelo-pé ativa. Atuadores elásticos em série são considerados neste trabalho, pois tais dispositivos apresentam características ideais para a sua utilização em órteses ativas: controle de força, controle de impedância (possibilidade de impedância baixa), absorção de impactos, baixo atrito e largura de banda que se aproxima da movimentação muscular. Um primeiro protótipo do atuador elástico em série foi construído e resultados experimentais de controle de força, impedância e posição foram obtidos com sucesso, através de uma interface de acionamento e controle entre o atuador, os sensores (encoders e sensores de força) e o computador. Também foi construída uma órtese tornozelo-pé ativa acionada pelo atuador elástico em série construído, sendo apresentados os primeiros resultados experimentais obtidos com este dispositivo. / This dissertation deals with the design and construction of series elastic actuators for driving the joints of an exoskeleton for lower limbs, based on a commercial orthosis. Initially, it was considered the construction of the exoskeleton\'s ankle joint, that is, the construction of an active ankle-foot orthosis. Series elastic actuators are considered in this work since these devices have ideal characteristics for use in active orthoses: force control, impedance control (possibility of low impedance), impact absorption, low friction and bandwidth that approximates the muscle movement. A first prototype of the series elastic actuator was constructed and experimental results of force, impedance, and position control were successfully obtained trough of a control interface between the actuators, the sensors (encoders and force sensors) and the computer. Also, an active ankle-foot orthosis, driven by the series elastic actuator, was constructed and the first experimental results achieved with this device are presented.

Os isópodos terrestres possuem uma cutícula protetora que mantém a forma corporal, permite locomoção e comunicação com o ambiente e protege contra dessecação, infecção e predação. Assim como nos demais crustáceos, a cutícula é composta por uma matriz orgânica que é mineralizada com cálcio. A cutícula é uma estrutura versátil que reflete adaptações ambientais e a ampla distribuição geográfica do grupo. Dessa forma, a ultraestrutura e a composição da cutícula variam entre espécies. Isópodos terrestres fazem mudas frequentes ao longo da vida para crescer e/ou renovar receptores de superfície, o que resulta em reabsorção e deposição cuticular constante. Esse grupo apresenta muda bifásica e deposição de placas de cálcio nos esternitos anteriores antes da ecdise como estratégia para reciclar o cálcio corporal. Estudos relacionados à cutícula nesse grupo contemplam a ultraestrutura, a composição e a deposição bem como o efeito de alguns fatores ambientais na muda. No entanto, poucos estudos exploram as ligações entre ecomorfologia e história de vida. Essa tese visa explorar diversos aspectos relacionados à cutícula e a muda de duas espécies neotropicais de isópodos terrestres. Atlantoscia floridana e Balloniscus glaber foram usados como modelo uma vez que são frequentemente encontrados nas mesmas localidades e diferem em tipo ecomorfológico e estratégias ambientais. No Capítulo I, foram exploradas as estruturas de superfície e a ultraestrutura da cutícula das duas espécies a fim de ver como as diferenças encontradas podem ser relacionadas à história de vida de cada espécie, utilizando técnicas de microscopia. As espécies diferiram em tipo e disposição das estruturas de superfície bem como em espessura e proporção de camadas da cutícula. De maneira geral, as diferenças das estruturas de superfície estão relacionadas à seleção de microhabitat e nicho ecológico. Características cuticulares ajudam a explicar o hábito endógeno de B. glaber e epígeo de A. floridana enquanto que as diferenças em ultraestrutura são relacionadas a estratégias comportamentais e tolerância ambiental. No Capítulo II, o efeito do cálcio alimentar no ciclo de muda das espécies foi testado. Para isso, dieta experimental e análise estrutural da cutícula foram realizadas a fim de entender como diferentes concentrações de cálcio alimentar interferem na duração do ciclo de muda. Peculiaridades na ecdise em A. floridana refletem morfologia específica do animal. A duração da intramuda foi maior em B. glaber assim como a sobrevivência média nos tratamentos. A duração do ciclo de muda foi influenciada pela concentração de cálcio; uma tendência a menor duração do ciclo com o aumento da concentração de cálcio foi observada em B. glaber, enquanto em A. floridana a diferença encontrada foi apenas entre o controle sem cálcio e os demais tratamentos. Não houve efeito da dieta no grau de mineralização ou na ultraestrutura em B. glaber. Independentemente do tratamento, a maior taxa de mortalidade em laboratório parece estar relacionada com o próprio processo de ecdise, com mortalidade acumulada de 20% do início da ecdise até o início da pós-muda para ambas as espécies. No Capítulo III, a secreção da cutícula durante a pré- e pós-muda muda foi observada utilizando microscopia de transmissão. A deposição seguiu o padrão observado para outros isópodos. Entretanto, grânulos eletrondensos presentes no espaço ecdisial durante a pré-muda são provavelmente constituídos de cálcio, sugerindo a reciclagem de cálcio diretamente da cutícula velha para a nova no mesmo segmento. Esses grânulos são depositados nas escamas na nova epicutícula antes da ecdise, sugerindo a presença de cálcio na superfície cuticular das espécies. Além disso, regiões sem a ultraestrutura típica encontrada na pós-muda indicam que há modificação na exocutícula após a ecdise uma vez que a expansão e endurecimento da nova cutícula apenas após a ecdise. De maneira geral, esse trabalho não apenas trouxe novas informações sobre a estrutura cuticular de duas espécies neotropicias, mas também contribuiu para esclarecer conexões entre ecomorfologia e requerimentos biológicos de isópodos terrestres. / Terrestrial isopods have a protective cuticle that maintains body shape, allows locomotion, enables communication with the environment and protects them against desiccation, infection and predation. As in all crustaceans, their cuticle is composed of an organic matrix that is mineralized with calcium. The cuticle is highly versatile reflecting adaptations to environmental conditions and large geographical distribution of this group. Therefore, cuticle ultrastructure and composition vary among species. Terrestrial isopods molt frequently throughout their lives in order to grow and/or renew surface receptors, resulting in constant cuticular resorption and deposition. In this group, this dynamics of cuticle formation is affected by the biphasic molt and by the calcium deposition on sternal deposits prior ecdysis, strategies to recycle body calcium. Studies related to cuticle on this group include ultrastructure, composition and deposition as well as effect of some environmental factors on molting. However, few studies explore connections of ecomorphology and life history of animals. This thesis aimed to explore various aspects of cuticle structure and molting using two Neotropical species of terrestrial isopods. Atlantoscia floridana and Balloniscus glaber were used as models since they are found in the same locations while differing in ecomorphology and behavioral strategies. In Chapter I, I explored the cuticle surface structures and ultrastructure of both species to see how their differences can be related to each species life history traits, using microscopy techniques. Species differed in surface structures type and disposition, as well as cuticle thickness and layer proportion. Overall, differences in surface structure are related to microhabitat selection and ecological niche. Cuticular features further explain the endogeic habit of B. glaber and epigeic habit of A. floridana, while differences in cuticle ultrastructure relate to behavioral strategies and environmental tolerance. Next, differences on molting cycle and environmental requirements were analyzed. In Chapter II, I tested the effects of dietary calcium on the molting cycle of both species. For that, artificial diet and structural analysis of the cuticle were used to understand how different concentrations of dietary calcium interfere with molt cycle duration. Peculiarities were observed during ecdysis in A. floridana and reflect to specific morphology of the species. Intramolt duration was longer for B. glaber as well as overall survivorship in treatments. Cycle duration was influenced by calcium concentration; a trend of shorter molt cycle length with increasing calcium concentration was observed for B. glaber, while in A. floridana, only difference between control without calcium and other treatments was observed. Degree of mineralization and cuticle ultrastructure of B. glaber showed no difference between treatments. Regardless of treatment or species, higher mortality rate under lab conditions seems to be related to the process of ecdysis itself, with cumulative mortality of 20% from the beginning of ecdysis until the beginning of postmolt. In Chapter III, I used transmission electron microscopy to analyze cuticle secretion in both species during pre- and postmolt stages. Cuticle deposition during premolt followed the same pattern as other terrestrial isopods. Nonetheless, electron dense granules present on the ecdysial space during premolt are likely calcium granules, suggesting the recycling of calcium within the same segment. These granules are deposited on the scales of the new epicuticle prior ecdysis, suggesting the presence of calcium on the cuticular surface of both species. Moreover, regions without typical lamellate ultrastructure during postmolt indicate modification of the exocuticle after ecdysis since expansion and hardening must occur after ecdysis. Overall, this work not only added information on cuticular structure of two Neotropical species but also clarified connections between ecomorphology and biological requirements of terrestrial isopods.

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No. of bitstreams: 2 Dissertação - Sémebber Silva Lino - 2018.pdf: 6051816 bytes, checksum: ea335e51b02781bbf65596b8422bac01 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2018-02-23 / Extension or flexion movements of the body in a healthy individual are routine physical activity in daily life, necessary for its autonomy and independence.Injuries to the spinal cord and brain are the main causes of paraplegia, which makes it impossible for human locomotion with autonomy. The use of a wheelchair will help them into your daily horizontal mobility. But the possibility of using an orthotic device to allow it to increase the amplitude of the movements of extension or flexion will help in maintaining your bone density, improving your blood circulation and enlargement of muscle tone, involving tension in muscles, arteries and other tissues organic well as excessive involuntary reflex. Therefore, this study aims to present a mathematical model to describe the trajectory of nodes corresponding to the movable joints and upper extremity of a low cost orthosestic device, of the exoskeleton type, to be coupled in the wheelchair, using computer simulation to determine the variation of positions and velocities of these joints associated with the articulations of the hip and lower limbs of the paraplegic wheelchair user, when performing extension or flexion movements of the body segments, besides the simulation of a prototype developed in CAD. As for the main results of the research, first, there is the trajectory of the nodes with respect the mobile joints and upper end using the representation of Denavit-Hartenberg, generated graphically by numerical and computer simulation, in order to validate and make feasible the mechanical construction of the device. Then, as the variation of the positions and velocities of motor gasket associated with the user’s knee joint device, has its graphical representation plucked by multistep interactive Runge-Kuta 4th Order, using the Lagrange equations for numerical and computational simulation of the transmission system drive, with the application of a torque on the crank of the robotic mechanism proposed, thus confirming its usability, reliability and security. Finally, the development of a 3D virtual prototype device CAD. Therefore, the preparation and provision of this manual orthotic device developed to assist in the vertical mobility of the paraplegic with spinal cord injury, will improve physical, psychological health, functional independence and daily well-being, and helping them in their autonomy to support on the feet. / Os movimentos de extensão ou flexão corporal em um indivíduo saudável são atividades físicas rotineiras necessárias para sua autonomia e independência. As lesões da medula espinhal e do cérebro são as principais causas da paraplegia, que impossibilitam a locomoção humana com autonomia. O uso de uma cadeira de rodas os auxiliará em sua mobilidade horizontal diária. Mas a possibilidade de uso de um dispositivo ortético que lhe permita aumentar a amplitude dos movimentos de extensão ou flexão, contribuirá na manutenção da sua densidade óssea, melhorando sua circulação sanguínea e ampliação do tônus muscular, envolvendo tensão em músculos, artérias ou outros tecidos orgânicos além de reflexos involuntários excessivos. Por conseguinte, este estudo objetiva apresentar um modelo matemático para descrever a trajetória dos nós correspondentes as juntas móveis e extremidade superior de um dispositivo ortético manual de baixo custo, do tipo exoesqueleto, a ser acoplado na cadeira de rodas do paraplégico, usando-se de simulação computacional para determinar a variação das posições e velocidades dessas juntas associadas às articulações do seu quadril e membros inferiores, ao realizar movimentos de extensão ou flexão dos segmentos corporais, além da simulação de um protótipo desenvolvido em CAD. Quanto aos principais resultados decorrentes da pesquisa, primeiramente, obteve-se a trajetória dos nós referentes às juntas móveis e extremidade superior utilizando-se da representação de Denavit-Hartenberg, gerada graficamente por simulação numérico- computacional, no intuito de validar e viabilizar a construção mecânica do dispositivo. Em seguida, a variação das posições e velocidades da junta motora associada à articulação do joelho do usuário do dispositivo, teve sua representação gráfica tangida pelo método interativo multipasso de Runge-Kuta de 4ª ordem, usando-se das equações de Lagrange para simulação numérico-computacional do acionamento do sistema de transmissão, com a aplicação de um torque na manivela do mecanismo robótico proposto, confirmando assim, a sua usabilidade, confiabilidade e segurança. Por último, o desenvolvimento de um protótipo virtual 3D em CAD do dispositivo. Portanto, a confecção e disponibilização desse dispositivo ortético desenvolvido para auxiliar na mobilidade vertical do paraplégico com lesão medular, melhorará sua saúde física, psicológica, independência funcional e bem-estar diário, auxiliando-o na autonomia para apoiar sobre os pés.