Статья посвящена обзору технических средств и методов регистрации электричес-ких сигналов с нервных волокон, возможных для применения в современных системах управления протезами. Авторами проведен сравнительный анализ различных конструкций имплантируемых микроэлектродов и материалов, из которых они изготавливаются, предложена классификация микроэлектродов. Рассмотрены основные проблемы регистра-ции нейросигналов и возможные пути их решения. Микроэлектродный массив; имплантируемый микроэлекртод; регис-трация нейросигнала

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ARECENT U.S. National Academy of Engineering and Institute of Medicine study (Building a Better Delivery System: A New Engineering/Health Care Partnership, National Academy Press, 2005) advocated the applications of system engineering tools and information/communication technologies to improve the quality and productivity of the healthcare system. Mechatronics design principle provides a synergistic integration of information, computation, and electromechanical device and systems, which plays an important role in advancing healthcare at both the device and system levels.

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Цель исследования: создание комплексной программы восстановления ходьбы у больных с инсультом с использованием роботизированных механотренажеров. В исследование включены пациенты в остром периоде инсульта, неспособные к самостоятельной ходьбе (средний возраст 59±10,4 года); 53 больных в основной группе и 25 — в контрольной. Среднее время от начала заболевания до начала проведения занятий с использованием роботизированных механотренажеров составило 14±1,6 суток и определялось адекватностью функциональных проб. Программа реабилитации включала ежедневные 30-минутные занятия лечебной физкультурой. Больные основной группы, в отличие от контрольной, получали также 20-минутные тренировки на роботизированных механотренажерах Motomed Viva 2 и Gait Trainer 1 (GT1), cопровождавшиеся непрерывным мониторингом артериального давления и частоты сердечных сокращений. Количество занятий на GT1 составило от 5 до 12, в среднем 7±1 занятие. После проведенного комплексного восстановительного лечения у пациентов основной группы по сравнению с контрольной отмечена достоверно (р<0,01) лучшая динамика по шкалам устойчивости стояния, функциональных категорий ходьбы, Берга, Бартел; все пациенты этой группы стали способны ходить с опорой или полностью самостоятельно. В основной группе достоверно (р<0,05) уменьшилось число больных с нарушениями проприоцептивной чувствительности (с 37,7 до 9,4%) и атаксией в нижних конечностях (с 37 до 11,3%), в контрольной группе динамики по этим показателям не было. Сделан вывод, что комплексное использование рефлекторной кинезотерапии и роботизированной механотерапии у больных в остром периоде инсульта позволяет увеличить функциональную активность и повысить уровень самообслуживания уже к моменту выписки из стационара.

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With the growing aging population, there is an increasing demand and oppor-tunity to develop exoskeletons, which are typically designed for military or industrial use, to be used on a daily basis to provide power assistance. Such exoskeletons could be used by the physically impaired and injured, in addition to the elderly. This report describes the design of a power-assist exoskeleton specifically for the pronation and supination motion of the forearm. The exoskeleton is controlled by two push-button sensors to indicate the direction of rotation, which is controlled by the user at all times. As a safety precaution, visual feedback was implemented to confirm the user’s inputs were received by the exoskeleton and that the robot is actuating. A stepper motor, whose torque is transferred to the system using a bidirectional winch system, is used such that the exoskeleton is able to output such holding torques to lock the position of the arm. The mechanical structure is composed of various PVC and ABS coupling hubs, which form a stationary and rotating unit. The exoskeleton is fixed onto the user’s forearm through a blood pressure cuff, and torque is transferred from the motor to the user’s wrist through a custom-carved Styrofoam wrist cuff. From testing, the average running torque of the system ranged from 5.24 Nm to 9.17 Nm for motor speeds from 60 rpm to 45 rpm, respectively, which confirmed that decreasing motor speeds increased running torque. The amount of holding torque could not be quantified because the testing setup was unable to produce sufficient loads (>55Nm) to move the system out of its fixed position. However, when in “idle”, the system still produced a holding torque of 30 Nm, suggesting a significant source of torque transfer loss in the system. The exoskeleton was worn by a user and tested for comfort, usability and overall functionality. While there were a few sources of discomfort that were expected, the robot was able to actuate the proper motions for the user and provide powered assistance. Overall, the system was able to pronate, supinate and hold the user’s forearm as controlled, demonstrating that the exoskeleton successfully provided powered-assistance.

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Mathematical models of a biped and quadruped walking are considered. The planar five-link biped consists of a one-link trunk and two identical two-link legs. In the single support motion
swing (phase), the biped has five degrees of freedom and is described by a system of nonlinear ordinary differential equations of the 10th order. These equations are written in a visible matrix form. A seven-link planar biped with massless feet is also considered. In this paper, the swing motion of the biped is assumed a ballistic
(passive) one. There are no active torques in the interlink joints during the single support motion—only the gravity force and ground reaction forces are applied to the biped. The problem of design of ballistic swing motion is reduced to the boundary-value problem for the system of nonlinear differential equations with given initial and final configurations and the duration of the half-step. It is assumed that there is no friction in the interlink joints (note that the friction in the human joints is very small). Therefore, in the ballistic swing motion the complete energy of the system
kinetic energy plus potential one is conserved and the system has the energy integral. Due to this fact some properties of symmetry of ballistic motions are proved. Linearized model can be reduced to the canonical Jordan form. Then the linear boundary-value problem can be solved analytically. Using numerical investigations of the linear model we have animated the biped walking, which occurs “similar” to the human gait: the transferring leg moves over the support, the legs bend with knees forward, and the trunk makes one vibration during one half-step. All these features have not been prescribed beforehand in the statement of the problem. Iteration process is used to solve the nonlinear boundary-value problem. For some cases, several solutions of this nonlinear problem are found numerically. The symmetry properties of the ballistic motions help to find numerically the solutions of this complex nonlinear problem. The ballistic motion is also designed numerically for the three-dimensional biped model and finally degrees of freedom. The double-support phase is assumed an instantaneous one. During this phase there is a collision of the transferring
swing leg and the support. Active impulsive torques are applied in the interlink joints at this instant. These impulsive torques and ground reaction forces are described by delta functions of Dirac. Thus, with this impulsive control, most of the efforts are applied in the double-support phase. Formulas for the energy cost of impulsive control actions have been found. Some problems of optimal distribution of the impulsive actions between the joints are discussed. A planar seven-link model of biped with arms is considered. This model consists of a one-link trunk, two identical one-link arms, and two identical two-link legs with point feet. Ballistic gait of this biped model is studied. The goal of this study is to find the optimal amplitude of the arms swinging, minimizing the energy consumption. We show numerically the existence of the optimal amplitude of the arms swinging. Ballistic walking of a quadruped is investigated too. Three types of quadruped gaits, bound, amble, and trot, are considered. For each kind of the gait, ballistic locomotion is designed and energy consumption is evaluated.

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