Mechatronics modeling and vibration analysis of a 2-DOF parallel manipulator in a 5-DOF hybrid machine tool

A hybrid machine tool is a complex mechatronic system and the complex interactions between the mechanical subsystem and the control subsystem have an important effect on the dynamic performance of the machine tool. In this paper, mechatronics modeling and forced vibration of a 2-DOF parallel manipulator in a 5-DOF hybrid machine tool are investigated. The mechatronics model is derived by using bond graph and the elastic deformation of the link with the lowest stiffness is considered in modeling. An approach to investigate the interactions between the mechanical subsystem and the control subsystem is proposed in frequency domain, by using the close-loop frequency response (CFR) of control loops and the frequency response function(FRF) of the moving platform. Based on the interactions between the mechanical subsystem and the control subsystem, the forced vibrations induced by motion command input and cutting forces are investigated, respectively. The results show that higher bandwidth and lower structural frequency lead to more interactions between the mechanical subsystem and the control subsystem. This paper explores bond graph techniques as a modeling tool, which can help engineers in the process of creating mechatronics system from scratch.