Research on performance optimization method of human-machine physical interaction system considering exoskeleton wearing comfort / 生物医学工程学杂志

In order to improve the wearing comfort and bearing effectiveness of the exoskeleton, based on the prototype and working mechanism analysis of a relaxation wearable system for knee exoskeleton robot, the static optimization synthesis and its method are studied. Firstly, based on the construction of the virtual prototype model of the system, a comprehensive wearable comfort evaluation index considering the factors such as stress, deformation and the proportion of stress nodes was constructed. Secondly, based on the static simulation and evaluation index of system virtual prototype, multi-objective genetic optimization and local optimization synthesis of armor layer topology were carried out. Finally, the model reconstruction simulation data confirmed that the system had good wearing comfort. Our study provides a theoretical basis for the bearing performance and prototype construction of the subsequent wearable system.

Development and Application of Lower Limb Exoskeleton Rehabilitation Robot / 中山大学学报(医学科学版)

With the deepening of the aging of society， there are more and more patients with motor dysfunction of lower limb，and rehabilitation therapy for these patients is becoming more and more important. Since the 1980s， exoskeleton robots for lower-limb rehabilitation have been applied to the rehabilitation for patient with dyskinesia， especially those with dyskinesia caused by neurological diseases such as stroke. These exoskeleton robots are wearable， nonlinear and complex mechanical devices， which deserve to be studied and widely applied. In this review， the research status， clinical application and challenges of exoskeleton robots for lower-limb rehabilitation are described in three aspects according to the difference of the therapeutic sites of exoskeleton rehabilitation robots， and on the basis， the development trend of exoskeleton robots for lower-limb rehabilitation is prospected.

A Review on Ergonomics Factors Determining Working in Harmony with Exoskeletons

@#Exoskeletons are wearable devices that can enhance human strength and are used in various fields, such as healthcare and the manufacturing industry. However, poorly designed exoskeletons can strain the muscles and cause injuries to users. The objectives of this review paper are to review the ergonomics factors that contribute to a harmonious user-exoskeleton interaction and to explore the current trends, challenges, and future directions for developing ergonomically designed exoskeletons. In this review, 102 relevant papers published from 2015 to 2023 were retrieved from Web of Science, Scopus, and Google Scholar. These papers were considered in the analysis for gathering relevant information on the topic. The authors identified six ergonomics factors, namely kinematic compatibility, contact pressure, postural control, metabolic cost, cognitive workload, as well as task demands and workplace conditions, that can influence the interaction between users and exoskeletons. By understanding and addressing these ergonomics factors during the design and development process, exoskeleton designers can enhance the user experience and adoption of the devices in daily living activities and industrial applications.

Evaluation method of assistance effect of extravehicular activity glove exoskeleton under weightlessness / 中国康复理论与实践

ObjectiveTo establish a multi index fusion hand grip fatigue prediction model to evaluate the power-assisted effect of the glove exoskeleton prototype for extravehicular clothing. MethodsBP neural network algorithm was used to establish a hand fatigue prediction model. The related factors of hand fatigue were determined with isometric grasping fatigue experiment, and the input variables of BP neural network were determined as cylinder diameter, grasping force, grasping duration and root mean square of electromyography. The fatigue data corresponding to variables of each group were obtained through experiments and subjective fatigue measurement scales, and a fatigue evaluation model based on multi-source fusion of BP neural network algorithm was established. The relationship model between fatigue and assistance effect was established, and the assistance effect of the exoskeleton prototype was evaluated through the degree of fatigue relief. ResultsThe correlation coefficient was 0.974 between the predicted results of the model and the target value. Moreover, it effectively predicted the assistance effect of different prototypes. ConclusionThe BP neural network model established by combining the grasping strength, grasping object parameters and human electromyography can predict hand fatigue, which can be used to evaluate the assistance effect of glove exoskeleton and other hand aids.

Training in a wearable exoskeleton improves the lower limb motor recovery of stroke survivors / 中华物理医学与康复杂志

Objective:To explore any differential effect of training wearing a unilateral exoskeleton on the lower-limb motor function of stroke survivors.Methods:Forty stroke survivors were randomly divided into an exoskeleton group ( n=20) and a control group ( n=20). The control group performed conventional lower extremity exercise training while the exoskeleton group received exoskeleton-assisted lower-limb physical therapy. Each participant received eighteen 40-minute training sessions over three weeks. Before and after the intervention, the walking ability, lower-limb function, balance and ability in the activities of daily living of both groups were evaluated. Integrated electromyography (iEMG) of the rectus femoris and tibialis anterior of both legs was also recorded during sit-to-stand transitions to assess the activation of the affected muscles and the symmetry of bilateral muscle activation. Results:After the three weeks, significant improvement was observed in all of the measurements in both groups, but with the exoskeleton group scoring significantly better on average in functional ambulation category grading (1.63±0.72). Both groups′ iEMGs had also improved significantly compared with before treatment, but the exoskeleton group′s average result was by that time significantly better than the control group′s average.Conclusions:A wearable exoskeleton can effectively improve the rehabilitation of walking, lower limb movement, balance and skill in the activities of daily living of persons with subacute stroke. It better activates the affected lower limb muscles and improves the symmetry of bilateral lower limb muscle activation.

Mechanical Design and Research of Wearable Exoskeleton Assisted Robot for Upper Limb Rehabilitation / 中国医疗器械杂志

Based on the biomechanical mechanism of human upper limb, the disadvantages of traditional rehabilitation training and the current status of upper limb rehabilitation robot, a six degree of freedom, flexible adjustment, wearable upper limb rehabilitation exoskeleton design scheme is proposed. Firstly, the mechanics of each joint of the upper limb is analyzed, and the virtual prototype design of the whole mechanical structure of the upper limb rehabilitation wearable exoskeleton is carried out by using CATIA three-dimensional software. The tooth transmission of the forearm and the upper arm single row four point contact ball bearing with internal/external rotation and the shoulder flexible passive adjustment mechanism (viscoelastic damper) are innovatively designed. Then, the joints of the upper limb rehabilitation exoskeleton are analyzed, theoretical analysis and calculation of the driving torque, the selection of the motor and gearbox of each driving joint are carried out. Finally, the whole finite element analysis of the upper limb exoskeleton is carried out. The research and experimental results showed that the design scheme of the upper limb exoskeleton assist structure is highly feasible, which can help the patients with upper limb paralysis and motor dysfunction self-rehabilitation.

Characteristic Analysis on Human-Machine Interaction Force of Lower Limb Exoskeleton / 医用生物力学

Objective To propose a human-machine coupling dynamics modeling method based on virtual muscles, so as to quantitatively analyze the characteristics of human-computer interaction force and muscle activation of the musculoskeletal system. Methods First, in the gait experiment of wearing exoskeleton, the human motion capture system and self-developed mechanical monitoring device were used to obtain the wearer’s walking dynamics, electromyography (EMG) signals, exoskeleton drive status and local human-computer interaction information. The human-machine coupling model was established in modeling environment of the bone system, and the gait experiment data and the exoskeleton joint torques were used as driving information of the coupling model to perform inverse mechanical calculations. Finally, by adjusting strength and stiffness parameters of the virtual muscles, the real data of the model was compared with the experimental test result, to quantitatively evaluate effectiveness of the human-machine coupling model of the lower extremity exoskeleton. Results The normal interaction force calculated by inverse dynamics of the coupled model and the activation of lower limb muscles had a good consistency in response curve trend compared with measurement results of the gait experiment, and the interaction force results had a high degree of correlation (r=0.931, P<0.01), the root mean square error was small, and the peak error of lower limb muscle activation was lower than 5%. Conclusions The human-machine coupling model proposed in this study can effectively calculate the interaction force between human and exoskeleton. The establishment of the coupling model provides a theoretical basis for verification and iteration of the exoskeleton structure optimization and control algorithm, as well as performance evaluation on mobility assistance effects of the exoskeleton.

A pace recognition method for exoskeleton wearers based on support vector machine-hidden Markov model / 生物医学工程学杂志

In order to improve the motion fluency and coordination of lower extremity exoskeleton robots and wearers, a pace recognition method of exoskeleton wearer is proposed base on inertial sensors. Firstly, the triaxial acceleration and triaxial angular velocity signals at the thigh and calf were collected by inertial sensors. Then the signal segment of 0.5 seconds before the current time was extracted by the time window method. And the Fourier transform coefficients in the frequency domain signal were used as eigenvalues. Then the support vector machine (SVM) and hidden Markov model (HMM) were combined as a classification model, which was trained and tested for pace recognition. Finally, the pace change rule and the human-machine interaction force were combined in this model and the current pace was predicted by the model. The experimental results showed that the pace intention of the lower extremity exoskeleton wearer could be effectively identified by the method proposed in this article. And the recognition rate of the seven pace patterns could reach 92.14%. It provides a new way for the smooth control of the exoskeleton.

Effects of ankle exoskeleton assistance during human walking on lower limb muscle contractions and coordination patterns / 生物医学工程学杂志

Lower limb ankle exoskeletons have been used to improve walking efficiency and assist the elderly and patients with motor dysfunction in daily activities or rehabilitation training, while the assistance patterns may influence the wearer's lower limb muscle activities and coordination patterns. In this paper, we aim to evaluate the effects of different ankle exoskeleton assistance patterns on wearer's lower limb muscle activities and coordination patterns. A tethered ankle exoskeleton with nine assistance patterns that combined with differenet actuation timing values and torque magnitude levels was used to assist human walking. Lower limb muscle surface electromyography signals were collected from 7 participants walking on a treadmill at a speed of 1.25 m/s. Results showed that the soleus muscle activities were significantly reduced during assisted walking. In one assistance pattern with peak time in 49% of stride and peak torque at 0.7 N·m/kg, the soleus muscle activity was decreased by (38.5 ± 10.8)%. Compared with actuation timing, the assistance torque magnitude had a more significant influence on soleus muscle activity. In all assistance patterns, the eight lower limb muscle activities could be decomposed to five basic muscle synergies. The muscle synergies changed little under assistance with appropriate actuation timing and torque magnitude. Besides, co-contraction indexs of soleus and tibialis anterior, rectus femoris and semitendinosus under exoskeleton assistance were higher than normal walking. Our results are expected to help to understand how healthy wearers adjust their neuromuscular control mechanisms to adapt to different exoskeleton assistance patterns, and provide reference to select appropriate assistance to improve walking efficiency.

The history of robotic surgery and its evolution: when illusion becomes reality / Evolução e história da cirurgia robótica: da ilusão à realidade

ABSTRACT The term "robot" was concepted in the beginning of last century, coming originally from the Czech word "robota", meaning "labor". More recently, computer assistance and robotics based in the telepresence and virtual reality concept have been applied to surgical procedures. The application of robots in surgery dates approximately 35 years, experiencing significant growth in the last two decades fueled by the advent of advanced technologies. Despite its recent and brief status in surgery history, robotic technology has already proven its enhanced visualization, superior dexterity and precision during minimally invasive procedures. Currently, the worldwide diffused and predominant robot system used in surgery is Da Vinci by Intuitive Surgical, however robotic surgery evolution is far from over, with multiple potential competitors on the horizon pushing forward its paradigms. We aim to describe the history and evolution of robotic surgery in the last years as well as present its future perspectives.

RESUMO O termo "robô" foi concebido no início do século passado, derivado originalmente da palavra tcheca "robota", que significa "trabalho". Mais recentemente, a tecnologia de computação associada à robótica, baseada no conceito de telepresença e realidade virtual, têm sido aplicadas aos procedimentos cirúrgicos. A aplicação de robôs em cirurgia data de aproximadamente 35 anos, experimentando um crescimento significativo nas últimas duas décadas impulsionado pelo advento de novas tecnologias e seus resultados. Apesar de seu status breve comparado à longevidade da história da cirurgia, a tecnologia robótica já provou seus potenciais benefícios com visualização aprimorada, destreza superior e maior precisão durante procedimentos minimamente invasivos. Atualmente, a plataforma robótica mundialmente difundida e predominantemente usada em cirurgia é o modelo Da Vinci da empresa Intuitive Surgical, e a evolução desse novo conceito de cirurgia está longe de terminar, com inúmeros competidores potenciais no horizonte impulsionando a quebra de paradigmas. Nosso objetivo nesta revisão é descrever a história e evolução da cirurgia robótica nos últimos anos, bem como apresentar suas perspectivas futuras.

Comparison between Thin-Layer Models and Non-Traditional Methods in the Modelling of Drying Kinetics of Crustacean Wastes

Abstract This research aims to compare the classical thin-layer models, stepwise fit regression method (SRG) and artificial neural networks (ANN) in the modelling of drying kinetics of shrimp shell and crab exoskeleton. Thus, drying curves were obtained using a convective dryer (3.0 m/s) at temperatures of 30.45 and 60oC. The results showed a decreasing tendency for the drying time as the temperature increased for both materials. Drying curves modelling of both materials showed fitted results with R 2 adj >0.998 and MRE<13.128% for some thin-layer models. On the other hand, by SRG a simple model could be obtained as a function of time and temperature, with the greatest accuracy being found in the modelling of experimental data of crab exoskeleton, with MRE<10.149%. Finally, the ANNs were employed successfully in the modelling of drying kinetics, showing high prediction quality with the trained recurrent ANN models.

Technical essential aspects in robotic colorectal surgery: mastering the Da Vinci Si and Xi platforms / Aspectos técnicos essenciais em cirurgia robótica colorretal: dominando as plataformas Da Vinci Si e Xi

ABSTRACT Background: laparoscopy surgery has many proven clinical advantages over conventional surgery and more recently, robotic surgery has been the emerging platform in the minimally invasive era. In the colorectal field, although overcoming limitations of standard laparoscopy, robotic surgery still faces challenging situations even by the most experienced colorectal surgeons. This study reports essentials technical aspects and comparison between Da Vincis Si and Xi platforms aiming to master and maximize efficiency whenever performing robotic colorectal surgery. Methods: this study overviews the most structured concepts and practical applications in robotic colorectal surgery in both Si and Xi Da Vinci platforms. Possible pitfalls are emphasized and step-wise approach is described from port placement and docking process to surgical technique. We also present data collected from a prospectively maintained database. Results: our early experience includes forty-four patients following a standardized total robotic left-colon and rectal resection. Guided information and practical applications for a safe and efficient robotic colorectal surgery are described. We also present illustrations and describe technical aspects of a standardized procedure. Conclusion: performing robotic colorectal surgery is feasible and safe in experienced surgeons hands. Although the Da Vinci Xi platform demonstrates greater versatility in a more user-friendly design with technological advances, the correct mastery of technology by the surgical team is an essential condition for its fully robotic execution in a single docking approach.

RESUMO Introdução: a cirurgia laparoscópica demonstrou vantagens sobre a cirurgia convencional e, mais recentemente, a cirurgia robótica tem sido a plataforma emergente na era cirúrgica minimamente invasiva. Na prática colorretal, embora supere as limitações da laparoscopia, a cirurgia robótica ainda enfrenta situações desafiadoras, mesmo diante de cirurgiões colorretais experientes. Este estudo relata aspectos técnicos essenciais e comparação entre as plataformas Si e Xi Da Vinci com o objetivo de auxiliar e maximizar a eficiência na realização de cirurgia robótica colorretal regrada. Métodos: este estudo apresenta uma visão geral dos conceitos essenciais e aplicações práticas em cirurgia robótica colorretal nas plataformas Da Vinci Si e Xi. As potenciais dificuldades são enfatizadas e uma abordagem em etapas é descrita desde a colocação dos portais e seu processo de docking até a técnica cirúrgica. Também apresentamos brevemente dados coletados de um banco de dados mantido de forma prospectiva. Resultados: nossa experiência inicial inclui quarenta e quatro pacientes submetidos à cirurgia totalmente robótica padronizada na ressecção colônica e retal. Informações e aplicações práticas para uma cirurgia robótica colorretal segura e eficiente são descritas. Também são apresentadas ilustrações e dados breves da experiência. Conclusão: a cirurgia robótica colorretal é viável e segura nas mãos de cirurgiões experientes, no entanto ainda enfrenta desafios. Apesar da plataforma Da Vinci Xi demonstrar maior versatilidade em um design mais amigável com avanços tecnológicos, o correto domínio da tecnologia pela equipe cirúrgica é condição essencial para sua execução totalmente robótica em etapa única.

Rehabilitación temprana de fracturas de radio distal con ortesis robóticas. Reporte de Casos / Early rehabilitation of distal radius fractures with robotic orthosis. Case Report

Introducción Los exoesqueletos robóticos son una nueva alternativa para complementar los procesos de rehabilitación funcional de la muñeca, facilitando la terapia de movilización pasiva temprana posterior a eventos traumáticos locales, con el propósito de mantener o restaurar el arco articular mientras cicatrizan los tejidos o consolidan las fracturas. El objetivo del estudio es presentar los resultados de la terapia de movilización temprana de forma pasiva mediante ortesis robóticas de muñeca. Materiales y Métodos Se seleccionaron cuatro pacientes con fracturas de radio distal, quienes fueron tratados quirúrgicamente con reducción abierta de la fractura más osteosíntesis con sistema de placa de bloqueo volar, fisioterapia convencional y movilización temprana con la órtesis robótica PRO-Wix; además, se hizo seguimiento clínico de la funcionalidad (escala DASH), del dolor (escala EVA), de los arcos de movilidad articular (goniómetro), de la adherencia y los potenciales eventos adversos. Resultados todos los pacientes se reintegraron a sus actividades de la vida diaria luego de tres semanas de rehabilitación, se registró recuperación del arco de movilidad articular, disminución de la intensidad del dolor, recuperación funcional, adecuada adherencia y no se presentaron eventos adversos. Discusión conservar al máximo la anatomía articular en la intervención quirúrgica especializada es la base para iniciar la rehabilitación temprana, y permitirá que el paciente tolere la movilización pasiva con órtesis robóticas.

Background Robotic exoskeletons are a new alternative to complement the functional rehabilitation processes of the wrist, facilitating early passive mobilization therapy after local traumatic events, with the purpose of maintaining or restoring joint range of motion while the tissues heal. The aim of the study is to present the results of early mobilization therapy in a passive robotic wrist orthosis. Methods Four patients with distal radius fractures were selected, treated surgically with open reduction and internal fixation of distal radius fracture with volar plate locking system. Conventional physiotherapy and early mobilization with the PRO-Wix robotic orthosis was performed. Clinical monitoring of functionality (DASH scale), pain (VAS scale), joint mobility arches (goniometer), adherence and potential adverse events were carried out. Results all patients returned to their daily living activities after three weeks of rehabilitation. Recovery of normal wrist joint range of motion was achieved; decreased in pain intensity, functional recovery, adequate adherence to rehabilitation protocol and adverse events were also recorded. Discussion preserving the joint anatomy as much as possible in specialized surgical intervention is the basis for starting early rehabilitation, and allowing the patient to tolerate passive mobilization with robotic orthoses. Further studies including a wide number of patients have to be conducted.

Comfort optimization of a new type of foot mechanism for lower extremity exoskeleton / 生物医学工程学杂志

In order to reduce the impact caused by the contact between the foot and the ground when wearing the lower extremity exoskeleton under the condition of high load, this paper proposed an exoskeleton foot mechanism for improving the foot comfort, and optimized the key index of its influence on the comfort. Firstly, the physical model of foot mechanism was established based on the characteristics of foot stress in gait period, and then the mathematical model of vibration was abstracted. The correctness of the model was verified by the finite element analysis software ANSYS. Then, this paper analyzed the influence of vibration parameters on absolute transmissibility based on vibration mathematical model, and optimized vibration parameters with MATLAB genetic algorithm toolbox. Finally, this paper took white noise to simulate the road elevation as the vibration input, and used the visual simulation tool Simulink in MATLAB and the vibration equation to construct the acceleration simulation model, and then calculated the vibration weighted root mean square acceleration value of the foot. The results of this study show that this foot comfort mechanism can meet the comfort indexes of vibration absorption and plantar pressure, and this paper provides a relatively complete method for the design of exoskeleton foot mechanism, which has reference significance for the design of other exoskeleton foot and ankle joint rehabilitation mechanism.

Sistema para medición y predicción de la intensión de movimiento / System for measurement and prediction of motion intention

En la actualidad, los dispositivos de asistencia para el movimiento humano como exoesqueletos se utilizan ampliamente para resolver problemas ergonómicos en tareas como el trabajo repetitivo, la rehabilitación, etc., esto permite mantener o mejorar el nivel de calidad de vida del usuario lo que permite nuevos movimientos o reduce la fatiga al final de un día de trabajo. El estudio y desarrollo de estos exoesqueletos requiere en gran medida parámetros externos (condiciones de operación y propósito) y parámetros internos del movimiento. Estos requisitos y características son aspectos fundamentales para detectar qué tipo de acción desea realizar en el proceso de movimiento del cuerpo. El control de los exoesqueletos que se utilizan en la actualidad se suele realizar manualmente o la reacción al movimiento detectado, causando problemas de demoras en la realización del movimiento o la incomodidad de llevar a cabo el mismo, por lo que hoy por hoy se realizan estudios para identifique de manera fiel la acción que el usuario intenta realizar y apoye el movimiento desde antes de que comenzara. El objetivo del proyecto es identificar de la intensión de movimiento de personas mediante señales de electroencefalografía y electromiografía de superficie como punto de partida para futuros métodos de control de exoesqueletos. Como resultado del estudio, se obtuvo el diseño y la implementación de un sistema para obtener, procesar e identificar señales electrofisiológicas para predecir la intención de movimiento de los miembros inferiores con porcentajes de aciertos superiores a 86,66 por ciento(AU)

At present, assistive devices for human movement such as exoskeletons are widely used to solve ergonomic problems in tasks such as repetitive work, rehabilitation, etc., this allows maintaining or improving the level of quality of life of the user which allows new movements or reduces fatigue at the end of a work day. The study and development of these exoskeletons largely requires external parameters (operating conditions and purpose) and internal movement parameters. These requirements and characteristics are fundamental aspects to detect what kind of action you want to perform in the process of body movement. The control of the exoskeletons that are currently used is usually done manually or the reaction to the movement detected, causing problems of delays in the realization of the movement or the discomfort of carrying out the movement, so studies are currently carried out to faithfully identify the action that the user tries to perform and support the movement from before it began. The objective of the project is to identify the intention of movement of people by means of electroencephalography and surface electromyography signals as a starting point for future exoskeleton control methods. As a result of the study, the design and implementation of a system was obtained to obtain, process and identify electrophysiological signals to predict the intention of movement of the lower limbs with success rates greater than 86.66 percent(AU)

Research progress on compliant characteristics of lower extremity exoskeleton robots / 生物医学工程学杂志

The lower extremity exoskeleton robot is a wearable device designed to help people suffering from a walking disorder to regain the power of the legs and joints to achieve standing and walking functions. Compared with traditional robots that include rigid mechanisms, lower extremity exoskeleton robots with compliant characteristics can store and release energy in passive elastic elements while minimizing the reaction force due to impact, so it can improve the safety of human-robot interaction. This paper reviews the compliant characteristics of lower extremity exoskeleton robots from the aspects of compliant drive and compliant joint, and introduces the augmentation, assistive, rehabilitation lower extremity exoskeleton robots. It also prospect the future development trend of lower extremity exoskeleton robots.

Construction and analysis of muscle functional network for exoskeleton robot / 生物医学工程学杂志

Exoskeleton nursing robot is a typical human-machine co-drive system. To full play the subjective control and action orientation of human, it is necessary to comprehensively analyze exoskeleton wearer's surface electromyography (EMG) in the process of moving patients, especially identifying the spatial distribution and internal relationship of the EMG information. Aiming at the location of electrodes and internal relation between EMG channels, the complex muscle system at the upper limb was abstracted as a muscle functional network. Firstly, the correlation characteristics were analyzed among EMG channels of the upper limb using the mutual information method, so that the muscle function network was established. Secondly, by calculating the characteristic index of network node, the features of muscle function network were analyzed for different movements. Finally, the node contraction method was applied to determine the key muscle group that reflected the intention of wearer's movement, and the characteristics of muscle function network were analyzed in each stage of moving patients. Experimental results showed that the location of the myoelectric collection could be determined quickly and efficiently, and also various stages of the moving process could effectively be distinguished using the muscle functional network with the key muscle groups. This study provides new ideas and methods to decode the relationship between neural controls of upper limb and physical motion.

Study on the influence of wearable lower limb exoskeleton on gait characteristics / 生物医学工程学杂志

The purpose of this paper was to investigate the effects of wearable lower limb exoskeletons on the kinematics and kinetic parameters of the lower extremity joints and muscles during normal walking, aiming to provide scientific basis for optimizing its structural design and improving its system performance. We collected the walking data of subjects without lower limb exoskeleton and selected the joint angles in sagittal plane of human lower limbs as driving data for lower limb exoskeleton simulation analysis. Anybody (the human biomechanical analysis software) was used to establish the human body model (the human body model without lower limb exoskeleton) and the man-machine system model (the lower limb exoskeleton model). The kinematics parameters (joint force and joint moment) and muscle parameters (muscle strength, muscle activation, muscle contraction velocity and muscle length) under two situations were compared. The experimental result shows that walking gait after wearing the lower limb exoskeleton meets the normal gait, but there would be an occasional and sudden increase in muscle strength. The max activation level of main lower limb muscles were all not exceeding 1, in another word the muscles did not appear fatigue and injury. The highest increase activation level occurred in rectus femoris (0.456), and the lowest increase activation level occurred in semitendinosus (0.013), which means the lower limb exoskeletons could lead to the fatigue and injury of semitendinosus. The results of this study illustrate that to avoid the phenomenon of sudden increase of individual muscle force, the consistency between the length of body segment and the length of exoskeleton rod should be considered in the design of lower limb exoskeleton extremity.

Research of a Wearable Lower Extremity Assisted Exoskeleton Robot System / 中国康复理论与实践

Objective:To propose a new type of lightweight wearable lower extremity exoskeleton assisted robot system, and explore the feasibility of walking and posture change rehabilitation training for patients with gait disorder and with paraplegia under T4 spinal cord injury (exclusion of lower extremity muscle spasm and obvious pain). Methods:The active and passive hybrid wearable lower extremity exoskeleton assisted robot structure of the hip joint with two-motor active drive and the knee joint passive four-link simulating the instantaneous movement of the human body was designed. Based on modular control, the STM32F767IGT6 and peripheral circuits, attitude acquisition, power supply and crutches module control system were proposed. The exoskeleton robot was worn by a normal person to perform the experiment of leveling, slope and posture transformation and analyze hip/knee /ankle joint angles during exercise, and compare the myoelectric signals of the lateral femoral and medial femoral muscles. Results:The wearer could realize the sitting-standing posture change and the flat/slope walking only based on the exoskeleton robot system, and the hip/knee/ankle angles were basically consistent with the normal walking and the electromyographic signals of the lateral femoral, medial femoral muscle significantly decreased when the robot was worn while walking. Conclusion:The active-passive hybrid lower exoskeleton assisted robot system can still achieve the rehabilitation of walking and posture change while reducing the weight. This verified the feasibility of the assisted robot system with the active dual-motor of the hip joint and the passive four-link structure of the knee joint to help the patients with paraplegia and gait disorder to walk and recover.

Sistema de biofeedback para rehabilitación de marcha asistida por un exoesqueleto / Biofeedback System for Exoskeletqn Assisted Gait Rehabilitation / Sistema de biofeedback para reabilitação de marcha assistida por um exoesqueleto

Resumen Los robots proporcionan nuevas formas de terapia para pacientes con desórdenes neurológicos. Las terapias de marcha asistidas con exoesqueletos pueden incrementar la duración y la intensidad de los entrenamientos para los pacientes y reducir el esfuerzo físico del terapeuta. Sin embargo, el uso de estos dispositivos para el entrenamiento de la marcha limita la interacción física entre el terapeuta y el paciente, en comparación con la terapia manual. Una apropiada realimentación de las funciones corporales y biomecánicas en la interacción con el sistema robótico facilita la evaluación del desempeño del paciente, motivándolo en el reaprendizaje de la marcha con resultados superiores. Este artículo presenta el diseño de una interfaz de usuario para un exoesqueleto de miembros inferiores para asistencia en la marcha y en terapias de rehabilitación. Se consideraron aspectos técnicos y clínicos para proporcionar ventajas del exoesqueleto durante las terapias, estableciendo una herramienta de apoyo para la configuración, monitoreo y registro de los parámetros involucrados. Se propuso un esquema de realimentación sensorial para el paciente acerca de la actividad muscular, la presión ejercida en diferentes puntos de los pies y algunas variables biomecánicas. Finalmente, se valida la herramienta con sujetos sanos por medio de un test de usabilidad propuesto.

Abstract The inclusion of robots in rehabilitation allow advantages for generate newer therapies in neurologic disorder patients. Assistive gait therapies using robots, like exoskeletons, allow increase the time and intensity training for patients while the strenuous labor of therapist is reduced. However, the physic interaction between therapist and patient in training with robots is limited, in relation to the traditional manual therapy. An appropriated feedback of biological and biomechanics functions in the robot interaction during training provides an easier performance evaluation of the patient for the therapist. Further, biofeedback gives a motivation to the patient and encourages him for gait relearning with higher effects than conventional. This paper presents a user interface design for a lower limb exoskeleton for human gait assistance in rehabilitation. Clinical and technical criteria for increasing the advantages of the exoskeleton in therapy were considered. A biofeedback scheme about muscle activity, plantar pressure and some biomechanics variables, for the patient is proposed. Finally, a validation for this tool with healthy subjects by a usability test was carried out.

Resumo A inclusão de robôs na reabilitação fornecem vantagens que promovem novas formas de terapia em pacientes com desordens neurológicas. Terapias de marcha assistidas por exoesqueletos permitem o aumento da duração e da intensidade dos exercícios com os pacientes, reduzindo o esforço físico dos terapeutas. Não entanto, o uso desses dispositivos para o treino da marcha limita a interação física entre o terapeuta e paciente, em comparação com a terapia manual. Uma apropriada realimentação das funções corporais e biomecânicas na interação com o sistema robótico facilita a avaliação do progresso do paciente, motiva e incentiva ao paciente na reaprendizagem da marcha gerando efeitos superiores aos convencionais. Neste artigo apresenta-se o desenho de uma interface de usuário para um exoesqueleto de membros inferiores para assistência na marcha e nas terapias de reabilitação. São considerados aspectos técnicos e clínicos para fornecer maiores vantagens do exoesqueleto durante as terapias, estabelecendo uma ferramenta de suporte para configuração, monitoramento e registro dos parâmetros envolvidos. Foi proposto um sistema de realimentação sensorial para o paciente sobre a atividade muscular, a pressão em diferentes pontos dos pés e algumas variáveis biomecânicas. Finalmente, é apresentada a ferramenta de validação para indivíduos saudáveis utilizando um teste de usabilidade proposto.