THE GEOMETRY OF THE SPATIAL FOUR-BAR MECHANISM AND OF ITS PARTICULAR FORMS

Starting from the rssr spatial four-bar mechanism, this paper analyses the most significant particular cases for which the specific transfer functions are written in comparison to the respective function deduced in the general case. From among the particular cases of the spatial mechanisms, the authors mention the oscillating washer mechanism and the cardan mechanism, demonstrating that spherical mechanisms can be obtained as the simplified variants in which the spherical joints may be replaced by simple rotation joints. For the spherical mechanism, the respective transfer functions have been determined as the simplest particular forms of the transfer function achieved by the rssr spatial four-bar mechanism.