A kinematic chain comprises a first pulley, arranged to rotate about a rotation axis x, and a second pulley arranged to rotate about a rotation axis y. The kinematic chain comprises then at least one connecting element comprising at least one passage having at least one rotating element, said or each connecting element also comprising at least one interface arranged to connect the connecting element to an adjacent connecting element or to a pulley, generating a rotational constraint about a rotation axis z. The kinematic chain also comprises a transmission element arranged to develop along a determined path for transmitting a rotational motion between the first pulley and the second pulley. The transmission element is adapted to be, in use, fixedly in contact with said or each rotating element by a constraint of rolling friction, in order to allow a modelling the determined path according to a predetermined geometry.