Influence of Friction Forces on Dynamics, Accuracy and Reliability of Piston Actuators with Intelligent Control

One of the factors significantly affecting the dynamics and accuracy of piston actuators is the relatively poorly studied friction in the piston. The paper presents the results of analyzing the motion of a drive with a pneumatic actuator as the most sensitive to the effects of friction forces, especially in the control of autonomous robotic systems. To model the dynamics of the actuator, special programs were developed to represent the actuator itself, its control system and separately the friction process. To describe the friction process, a rather well-developed Karnopp model was used, which is well suited for correct representation of the friction effect in the considered actuators, in particular the “stick-slip” (SS) effect characteristic of sliding seals. Moreover, this model is very efficient in numerical computations and, therefore, has been widely used in works on frictional motion modeling and control. The main focus of the work is on neutralizing the effects of friction forces. Due to the complexity of the models of these forces and the difficulty of obtaining data on their structures and parameters, a rather general and widely accepted model of friction forces, transformed to a dimensionless form together with other blocks of the general model, is adopted in this work. These results are planned to be used in the creation of robotic systems with artificial intelligence.