This document presents a low-pressure servo-valve specifically designed for haptic interfaces and lightweight robotic applications. The device is able to work with hydraulic and pneumatic fluidic sources, operating within a pressure range of (0 − 50 ·10⁵ Pa). All sensors and electronics were integrated inside the body of the valve, reducing the need for external circuits. Positioning repeatability as well as the capability to fine modulate the hydraulic flow were measured and verified. Furthermore, the static and dynamic behavior of the valve were evaluated for different working conditions, and a non-linear model identified using a recursive Hammerstein-Wiener parameter adaptation algorithm.

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For decades, robotic devices have been suggested to enhance motor recovery by replicating clinical manual-assisted training. This paper presents an overground gait rehabilitation robot, which consists of a pair of robotic orthoses, the connected pelvic arm in parallel and a mounted mobile platform. The overground walking incorporates pelvic control together with active joints on the lower limb. As a preliminary evaluation, system trials have been conducted on healthy subjects and a spinal cord injury (SCI) subject, respectively. Electromyography signals were recorded from muscles of the lower limb for each subject. Three experiments were carried out: (i) health volunteers walking at self-preferred walking speed, (ii) a SCI subject walking with the help of three helpers and (iii) the same SCI subject walking with the assistance provided by the gait device. In the experiment, the muscle activation of overground walking was compared between the manual-assisted and robotic-assisted methods. The initial results show that the performance of the device can provide impact-less overground walking and it is comparable to the performance obtained by manual assistance in gait rehabilitation training.

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The movements of the shoulder, elbow, and wrist play a vital role in the performance of essential daily activities. We therefore have developed a 2DOF exoskeleton robot (ExoRob) to rehabilitate the elbow and forearm movements of physically disabled individuals with impaired upper-limb function. The proposed ExoRob is supposed to be worn on the lateral side of forearm in order to provide naturalistic range movements of elbow (flexion/extension) and forearm (pronation/supination) motions. This paper focuses on the modelling, design (electrical and mechanical components), development, and control of the proposed ExoRob. The kinematic model of ExoRob has been developed based on modified Denavit-Hartenberg notations. Non-linear modified computed torque control technique is employed to control the proposed ExoRob, where trajectories (i.e., pre-programmed trajectories recommended by therapist/clinician) tracking corresponding to typical rehabilitation (passive) exercises has been carried out to evaluate the performances of the developed ExoRob and controller. Furthermore, experiments were carried out with the master exoskeleton arm [mExoArm, an upper-limb prototype 7DOF (lower scaled) exoskeleton arm] where subjects (robot users) or experimenter operate the mExoArm (like a joystick) to manoeuvre the proposed ExoRob to provide passive rehabilitation. Experimental results show that the controller is able to manoeuvre the ExoRob efficiently to track the desired trajectories. Such movements are widely used in rehabilitation and have been performed efficiently with the developed ExoRob and the controller.

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This paper reports the integration of a kinematic model of the human hand during cylindrical grasping, with specific focus on the accurate mapping of thumb movement during grasping motions, and a novel, multi-degree-of-freedom assistive exoskeleton mechanism based on this model. The model includes thumb maximum hyper-extension for grasping large objects (~>;50mm). The exoskeleton includes a novel four-bar mechanism designed to reproduce natural thumb opposition and a novel synchro-motion pulley mechanism for coordinated finger motion. A computer aided design environment is used to allow the exoskeleton to be rapidly customized to the hand dimensions of a specific patient. Trials comparing the kinematic model to observed data of hand movement show the model to be capable of mapping thumb and finger joint flexion angles during grasping motions. Simulations show the exoskeleton to be capable of reproducing the complex motion of the thumb to oppose the fingers during cylindrical and pinch grip motions.

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The aim of rehabilitation robotic area is to research on the application of robotic devices to therapeutic procedures. The goal is to achieve the best possible motor, cognitive and functional recovery for people with impairments following various diseases. Pneumatic actuators are attractive for robotic rehabilitation applications because they are lightweight, powerful, and compliant, but their control has historically been difficult, limiting their use. This article first reviews the current state-of-art in rehabilitation robotic devices with pneumatic actuation systems reporting main features and control issues of each therapeutic device. Then, a new pneumatic rehabilitation robot for proprioceptive neuromuscular facilitation therapies and for relearning daily living skills: like taking a glass, drinking, and placing object on shelves is described as a case study and compared with the current pneumatic rehabilitation devices.

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