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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A lower limb orthotic device (100) includes a thigh link (101) connected to a hip link (102) through a hip joint (103). a hip torque generator (106) including a hip actuator (110) and a first mechanical transmission mechanism (111) interposed between the thigh link ( 101) and the hip link (102), a shank link (104) connected to the thigh link (101) through a knee joint ( 105), a knee torque generator ( 107) including a knee actuator (112) and a second mechanical transmission mechanism (113) interposed between the thigh link (101) and the shank link (104), and a controller (108), such as for a common motor (154) and pump (156) connected to the hip and knee torque generators (106, 107), for regulating relative positions of the various components in order to power a user through a natural walking motion, with the first and second mechanical transmission mechanisms (111, 113) aiding in evening out torque over the ranges of motion, while also increasing the range of motion where the torque generators (106, 107) can produce a non-zero torque.

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The present invention provides a rehabilitation device using a walking assistance device (1) having an actuator which generates and provides torque to a lower limb joint of a wearer wearing the walking assistance device (1), comprising a floor reaction force pattern storing unit (330) configured to store a reference floor reaction force pattern; a control target floor reaction force setting unit (340) for determining a control target floor reaction force based on the floor reaction force pattern stored in the floor reaction force pattern storing unit (330); a target torque calculating unit (350) for calculating a target torque of the actuator to achieve the control target floor reaction force determined by the control target floor reaction force setting unit (340); and an actuator output controller (150) for controlling output of the actuator such that the actuator generates a torque matching the target torque calculated by the target torque calculating unit (350); wherein the floor reaction force that the wearer receives is increased and decreased by the application of torque generated by the actuator.

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Acquiring neural signals at high spatial and temporal resolution directly from brain microcircuits and decoding their activity to interpret commands and/or prior planning activity, such as motion of an arm or a leg, is a prime goal of modern neurotechnology. Its practical aims include assistive devices for subjects whose normal neural information pathways are not functioning due to physi-cal damage or disease. On the fundamental side, researchers are striving to decipher the code of multiple neural microcircuits which collectively make up nature’s amazing computing machine, the brain. By implanting biocompatible neural sensor probes directly into the brain, in the form of microelectrode arrays, it is now possible to extract information from interacting populations of neural cells with spatial and temporal resolution at the single cell level. With parallel advances in application of statistical and mathematical techniques tools for deciphering the neural code, extracted populations or correlated neurons, significant understanding has been achieved of those brain commands that control, e.g., the motion of an arm in a primate (monkey or a human subject). These developments are accelerating the work on neural prosthetics where brain derived signals may be employed to bypass, e.g., an injured spinal cord. One key element in achieving the goals for practical and versatile neural prostheses is the development of fully implantable wireless microelectronic Bbraininterfaces within the body, a point of special emphasis of this paper.

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В данной статье вы найдете краткое техническое описание проекта и большое кол-во фотографий лаборатории и экзоскелета Body Extender.

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Категория: Body Extender | 10 комментариев »