The influence of the hydraulic fluid compressibility on the kinematics of mechanism actuated with hydraulic cylinders

Résumé

In the description of the kinematics of mechanisms driven by hydraulic cylinders, hydraulic agent is usually considered incompressible. This computing hypothesis introduces errors which, in certain situations, can not be accepted. The volume of hydraulic agent sent by hydraulic pump it changes due to its compressibility. As a result, differences appear on the positioning of mobile elements. This paper presents a method of evaluation by calculation of this kind of influence on the positioning accuracy of the moving parts of the mechanism analyzed.