Abstract: A method for actuating a mechanism imposing a prefixed relative movement between a first and a second rigid link and a hand exoskeleton obtained by utilizing the method. The mechanism includes revolute joints and may be a parallelogram mechanism, a pantograph remote center of rotation mechanism, or a multiple-degrees-of-freedom mechanism. The method provides coaxially arranging at one or more selected revolute joints a number of idle pulleys which are greater than the number of degrees of freedom of the mechanism, the first of the selected revolute joints preferably having its rotation axis fixed with respect to the rigid link; the method also provides arranging an inextensible cable between a traction point and a terminal point on the mechanism or on the second rigid link.

Abstract: A high torque limited angle compact and lightweight actuator that comprises a driven pulley (11), a flexible tie-member (6), which is wound about the driven pulley (11), a linear actuator (7) and an inversion mechanism (8). In particular, the linear actuator (7), which is located with respect to the driven pulley (11) such that the direction is substantially tangent to it, comprises a movable element (10) that carries out a linear movement along a line according to two opposite directions (10?), (10?). The inversion mechanism is such that when an input portion (8?) moves along a line (first straight line), tangential to the driven pulley, of a certain an amount a output portion (8?) moves along another line (second straight line), which is also tangential to the driven pulley, for a same movement amount, such that the total length of the tie-member (6) is unchanged. (FIG.