Active control method and system for milling chattering time delay of motorized spindle

Abstract

The invention relates to an active control method and system for milling chattering time delay of a motorized spindle. The method and the system are applied to the motorized spindle comprising an actuating device. The method comprises the steps: inputting vibrating signals acquired from mutually-orthogonal directions of a motorized spindle system, measured motorized spindle system parameters and a cutting force coefficient to a continuous-milling chattering active control state equation containing state time delay; carrying out discretization on the continuous-milling chattering active control state equation, then, calculating optimal active control force for the motorized spindle system by using a discrete optimal control algorithm, and then obtaining a driving voltage which drives a piezoelectric actuator to apply the active control force to the motorized spindle system. By adopting the method or the system provided by the invention, the chattering during milling can be effectively inhibited, a stable region of milling is enlarged, the machining effect is improved, and the machining efficiency is increased.

Description

technical field [0001] The present disclosure belongs to the technical field of mechanical cutting processing control, and more particularly relates to an active control method and system for chatter time delay in milling processing. Background technique [0002] Milling is widely used in aviation, aerospace, mold and other industries. In milling, chatter is a key factor restricting the quality of machined surfaces and productivity. Chatter is a dynamic instability phenomenon of the closed-loop cutting system composed of machine tool-tool-workpiece. It is rooted in the abnormal change of cutting force, resulting in very strong and continuous relative vibration between the tool and the workpiece. Chatter is a self-excited vibration phenomenon in cutting machining, among which regenerative chatter (self-excited chatter excited by dynamic milling force caused by the change of milling thickness) is the main factor causing vibration. Cutting chatter will leave chatter marks on ...

AI Technical Summary

Problems solved by technology

Mathematical modeling of the milling system, experimental determination of the dynamic parameters of the system, and then design of the control algorithm are the core of the active control of chatter; however, the milling dynamics system is relatively complex, and the complexity of the milling process is not only due to the time delay in the system Existence is also due to the periodicity of the rotary cutting motion of the cutter teeth during the milling process, which leads to periodic changes in the coefficients in the milling dynamics equation, which increases the difficulty of the design of the control algorithm

Therefore, the design of active chatter control methods in milling is very challenging

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