INFLUENCE OF ELASTIC FORCES ON MOVEMENT ACCURACY OF PARALLEL MANIPULATOR
During the mechanisms’ operation, elastic forces can arise in their links, which can affect the motion accuracy and, as a result, the overall performance. This paper studies the influence of such forces on the motion of a parallel manipulator with six degrees of freedom. The considered manipulator has three kinematic chains, each of which contains a piercing rod connecting an output link with a base. The article presents a mathematical model that describes the deformations of the rods’ parts located in the manipulator workspace. It is found that there are two bending forces and one tension force in each rod. Based on Newton-Euler equations, the equations of output link motion were derived concerning the obtained expressions for the elastic forces. MATLAB package was used to simulate the motion for two different materials of the rods: aluminum and steel. It is shown that oscillations are superimposed on a desired motion of the output link. For each case, the graphs of the calculated movement were plotted and the largest deviations from the specified trajectory were determined.