This paper investigates the control algorithm of an exoskeleton for hand rehabilitation, which accomplishes both active and passive rehabilitation training. In the passive mode control the PID control algorithm is executed in the velocity mode of the driver. In the active mode control, control architecture is proposed to deal with in both free space and constraint space. A resistance compensation control method is proposed to reduce the resistance in free space which is caused by the friction of the Bowden cable as well as the moment of inertial. To realize the compensation, force sensors are used to measure the force exerted by the human fingertip. A commercial driver, which could switch between the two control modes by a programmable digital switch rather than changing the physical connection manually, guarantees the realization of the required functions. The experiments are conducted to verify the proposed method, and the results show that in the active control mode, the maximum finger-exerted force with compensation is about two fifths of the force without compensation which means the resistance is greatly reduced. And in the passive mode, the maximum joint position error is about 1.2 degree, which satisfies the requirement in hand rehabilitation application. The experimental results demonstrate the validity of the proposed method.

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For the human hand rehabilitation, the palmar opposition is an important function to evaluate the recovery of hand motor capabilities. This paper proposes an exoskeleton-type hand rehabilitation assistive device which is able to be applied to index finger as well as thumb. The kinematics and workspace of index fingertip and thumb-tip are analyzed. The `opposition space’ is defined as the intersection of the workspace of thumb-tip and the index fingertip. A metric, what we call `opposition degree’, which is defined as the ratio of volume of opposition space to that of the index fingertip workspace, is proposed to present the available degree of opposition. As an example, the opposition degree of a human hand model is determined. This metric can also used to rate the ergonomic performance of the hand rehabilitation assistive device. This method can be applied to other fingers as well. The opposition simulation experiment is conducted to verify the kinematics of the proposed exoskeleton.

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Точнее сказать, водой следует заправлять новое устройство, которое способно поставлять энергию для любой переносной электроники в чистом поле днём и ночью, поскольку не зависит от розеток или солнечного света. Инновация понравится военным, спортсменам и путешественникам.

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