Comparing with hip and knee, the design of exoskeleton ankle is much more difficult due to the strict requirements of smaller space, better rigidity and heavier load. A novel ankle exoskeleton with 3-RPS (Revolute- Prismatic-Spherical) parallel mechanism, which can fully sustain the heavy load of human body with good dynamic and kinematic performances, has been conducted to assist rehabilitation of the physically weak persons. The 3-RPS parallel mechanism of ankle joint is optimized in detail. The skin surface electromyographic (sEMG) signals of muscles are applied as main input signals. By preprocessing the sEMG signals, a new neuro-fuzzy controller is developed to predict the user’s motion and control the robotic exoskeleton in real time. The experimental results prove that EMG-based neuro-fuzzy controller is effective, and the parallel ankle with higher stiffness and lighter weight meets the kinematical and dynamical requirement for rehabilitation.

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Based on the complex and compact structure of lower extremity exoskeleton electronic system, a fault diagnosis model based on immune evolution algorithm is given and the design and realization method of the intelligent fault diagnosis system is also presented. According to the defects of immune algorithm that the individual diversity calculation is very complex and the vaccination is difficult, a fault calculation mechanism integrated the induction and statistic is designed, which introduced new immune operators that realized by vaccination, adjustment of diversity of every locus and immune selection. The strategies of calculating, judging and adjusting the diversity of populations by calculating the locus information entropy, the effects of control parameters, the methods of selecting and constructing a vaccine using the system information are all given. The fault diagnosis experiment results show the validity of this method based on immune algorithm, which improve speed and precision of diagnosis.

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It is important for a wearable robot to be compact and sufficiently light for use as an assistive device. Since human fingers are arranged in a row in dense space, the concept of traditional wearable robots using a rigid frame and a pin joint result in size and complexity problems. A structure without a conventional pin joint, called a jointless structure, has the potential to be used as a wearable robotic hand because the human skeleton and joint can replace the robot’s conventional structure. Another way to reduce the weight of the system is to use under-actuation. Under-actuation enables adaptive grasping with less number of actuators for robotic hands. Differential mechanisms are widely used for multi-finger under-actuation; however, they require additional working space. We propose a design with a jointless structure and a novel under-actuation mechanism to reduce the size and weight of a hand exoskeleton. Using these concepts, we developed a prototype that weighs only 80 grams. To evaluate the prototype, fingertip force and blocked force are measured. Fingertip force is the force that can be applied by the finger of the handexoskeleton on the object surface. The fingertip force is about 18 N when actuated by a tension force of 35 N from the motor. 18 N is sufficient for simple pinch motion in daily activities. Another factor related to performance of the under-actuation mechanism is blocked force, which is a force required to stop one finger while the other finger keeps on moving. It is measured to be 0.5 N, which is sufficiently small. With these experiments, the feasibility of the new hand exoskeleton has been shown.

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This paper proposes a novel design of a hand exoskeleton System. The optimisation of the exoskeleton device (link lengths, actuation) was achieved through the procedure targeting the natural finger workspace and capabilities. To define the design requirements of the hand exoskeleton device, an analysis of the hand daily life common activities has been carried out. Range of motion, maximum and average force levels exerted by human hands of different sizes and various age groups have been measured using appropriate instrumentation. Results of these experiments mapped directly to the mechanical design of the system. An under-actuated optimum mechanism has been proposed. A rapid prototype of the proposed design has been realized to analyze and demonstrate the mechanism and to verify the optimisation results. Results have shown that the hand exoskeletonsystem covers the complete range of motion of a natural human hand.

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Rehabilitation based on robot has been important researches field. In this paper, an exoskeleton device for upper limb has been developed, and it includes three active DoFs (Degree of Freedoms) and four passive DoFs. This device is used to assist performance for the impaired upper limb. Hemiplegic patients can move their intact upper limb by manipulating a haptic device (Phantom Premium) and their impaired upper limb can move synchronously, which is driven by the exoskeleton device. Different from general joystick, haptic device not only exert force to patients, but also can detect the movement of upper limb because of its 6 DoFs and enough work range. Therefore, the impaired upper limb can perform following the intact upper limb and patients can perform some rehabilitation by themselves. In this paper we focused on the motion detection of intact limb. Control onexoskeleton device was discussed in previous work. Also this system can be used in remote rehabilitation.

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