Study of the dynamics of the hydraulic drive of the boom lifting mechanism of a forestry manipulator with a magnetic damping device

An analysis of current research on the dynamics of hydraulic drives for crane manipulators used in hoisting machines is conducted. It is established that the application of damping devices in crane lifting mechanisms and their mathematical modeling in transient conditions have been insufficiently studied to date. A design scheme for a hydraulic drive for a crane boom lift mechanism with an engaged magnetic damping device, which ensures energy redistribution and suppression of dynamic effects, is proposed. The objective of this study is to evaluate the effectiveness of the proposed magnetic damping device and the developed mathematical model for reducing dynamic loads in the hydraulic drive of a forestry crane boom lift. A mathematical model of the hydraulic drive dynamics has been developed, based on recurrent computational schemes with explicit time discretization. This ensures correct consideration of the nonlinear properties of the system and made it possible to obtain time dependencies of pressure, boom lift angle, and magnetic piston stroke in the damping device. Numerical simulation results showed that the use of a magnetic damping device reduces maximum dynamic pressure in the boom lift hydraulic system by 1.4–1.5 times compared to operating without damping. Pressure stabilizes at approximately 25 MPa, whereas in the control mode without a damper, it fluctuates between 31–39 MPa, accompanied by pronounced oscillations.