Moving a brain–computer interface (BCI) system from a laboratory demonstration to real-life applications still poses severe challenges to the BCI community. This study aims to integrate a mobile and wireless electroencephalogram (EEG) system and a signal-processing platform based on a cell phone into a truly wearable and wireless online BCI. Its practicality and implications in a routine BCI are demonstrated through the realization and testing of a steady-state visual evoked potential (SSVEP)-based BCI. This study implemented and tested online signal processing methods in both time and frequency domains for detecting SSVEPs. The results of this study showed that the performance of the proposed cell-phone-based platform was comparable, in terms of the information transfer rate, with other BCI systems using bulky commercial EEG systems and personal computers. To the best of our knowledge, this study is the first to demonstrate a truly portable, cost-effective and miniature cell-phone-based platform for online BCIs.

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Embodiments of the hyperextension brace assembly utilize a cross-strap attached to mounting facilities about a joint to limit the extension of limbs about the joint. The cross-strap assembly is positioned from a cross origin behind the joint to attachment points on upper and lower mounting facilities on the upper and lower limbs and provides an opposing tensile force that limits the extension of mounting facilities and the limbs. In embodiments for a knee joint, the brace assembly provides a resisting force to resist hyperextension of the knee. Embodiments of the assembly are able to accommodate different joints, different size wearer’s of the assembly and different tension settings such as for athletes during competition. Embodiments of the brace can be used bilaterally and can be made without metal bracing to comply with the requirements of some sports.

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Background The majority of stroke survivors have to cope with deficits in arm function, which is often measured with subjective clinical scales. The objective of this study is to examine whether circle drawing metrics are suitable objective outcome measures for measuring upper extremity function of stroke survivors. Methods Stroke survivors (n = 16) and healthy subjects (n = 20) drew circles, as big and as round as possible, above a table top. Joint angles and positions were measured. Circle area and roundness were calculated, and synergistic movement patterns were identified based on simultaneous changes of the elevation angle and elbow angle. Results Stroke survivors had statistically significant lower values for circle area, roundness and joint excursions, compar-ed to healthy subjects. Stroke survivors moved significantly more within synergistic movement patterns, compared to healthy sub-jects. Strong correlations between the proximal upper extremity part of the Fugl-Meyer scale and circle area, roundness, joint ex-cursions and the use of synergistic movement patterns were found. Conclusions The present study showed statistically significant differences in circle area, roundness and the use of synergistic movement patterns between healthy subjects and stroke survivors. These circle metrics are strongly correlated to stroke severity, as indicated by the proximal upper extremity part of the FM score.

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This paper addresses the problem of modelling, control, and simulation of a mechanical system actuated by an agonist-antagonist musculotendon subsystem. Contraction dynamics is given by case I of Zajac’s model. Saturated semi positive proportional-derivative-type controllers with switching as neural excitation inputs are proposed. Stability theory of switched system and SOSTOOLS, which is a sum of squares optimization toolbox of Matlab, are used to determine the stability of the obtained closed-loop system. To corroborate the obtained theoretical results numerical simulations are carried out. As additional contribution, the discussed ideas are applied to the biomimetic control of a DC motor, i.e., the position control is addressed assuming the presence of musculotendon actuators. Real-experiments corroborate the expected results.

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The present invention relates to variable low/zero gravity simulation systems. variable low/zero gravity condition is achieved by substantial immersion in a fluid environment (“buoyancy means”) and using power assist means/robotic displacement devices such as exoskeleton to help user’s movement/gravity compensation and/or relief or change loads on the subject’s torso and limbs that caused by the weight and shape of the “Buoyancy means”, so that user can experience the effect of the (variable) gravity environment being simulated, such as Zero gravity in which situation user could move effortlessly in a weightless environment. When combine with VR related technology, this can create vivid immersive simulations for extraterrestrial scenes and can be widely used for entertainment, game, training, healing and etc.

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