Measurement device and measurement method of torsional vibration modal of numerical control machine

Abstract

The invention discloses a measurement device and a measurement method of a torsional vibration modal of a numerical control machine. The measurement device comprises a Hall sensor, a data acquisition card, a high-resolution rotary encoder, a counter, a parametric recognition module and a computer. The measurement method comprises the following steps: generating a series of sinusoidal waves with the same vibration amplitude and the same variable frequency by utilizing a numerical control device; measuring the current signal of a servo motor to obtain the drive torque of the servo motor; measuring the rotational angular velocity of a screw rod through the high-precision rotary encoder; respectively carrying out Fourier transform on a sampled angle velocity signal and the motor torque, and solving the specific value of the sampled angle velocity signal to the motor torque; solving a transfer function between all measuring points on the motor torque and the screw rod; and identifying the torsional vibration modal parameter of a motor rotor-screw rod system by utilizing a weighted least squares method to obtain inherent frequency and a modal shape of each order of torsional vibration. By the measurement device and the measurement method, the torsional vibration modal of a ball screw feeding drive mechanism of the numerical control machine can be rapidly and accurately measured, andthe torsional dynamical characteristics are analyzed; the measurement device and the measurement method provide the scientific basis for the design of the ball-screw feeding drive mechanism and the vibration control, and are applied to the measurement of the torsional vibration modal of the numerical control machine.

Description

technical field [0001] The invention relates to a measuring device for the dynamic performance of a numerically controlled machine tool, in particular to a measuring device for the torsional vibration mode of a numerically controlled machine tool. Background technique [0002] High-speed machining technology is one of the most important common technologies in modern advanced manufacturing technology. It represents the development direction of cutting processing and has gradually become the mainstream technology of cutting processing. High-speed machining technology must first have a high-speed spindle, and the high-speed spindle must be installed on a machine tool whose structure can adapt to high-speed cutting in order to give full play to the many advantages of high-speed cutting. This requires that the feed drive system of the machine tool must have High acceleration to achieve high feed rate. [0003] At present, the feed drive system of CNC machine tools mostly uses ba...

AI Technical Summary

Problems solved by technology

However, there is still a lack of effective means to accurately measure the torsional vibration mode of the ball screw feed drive mechanism of CNC machine tools

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