Dynamic precision oriented numerical control system interpolation generation motion instruction evaluation method

Abstract

The invention provides a dynamic precision oriented numerical control system interpolation generation motion instruction evaluation method. The method comprises the following steps of: firstly, collecting an instruction speed, an instruction acceleration and an instruction jerk sequence which are output to each shaft servo system after interpolation; then performing time-frequency transform to obtain a corresponding time-frequency graph; and finally, calculating a curve of an instruction speed high frequency band ratio which changes over time, namely changes with the tool path according to theinstruction speed time-frequency graph, thereby reflecting ability of the numerical control system interpolation generation motion instruction to realize position following precision; respectively calculating a curve of a frequency band ratio near a low order mechanical natural frequency of the instruction acceleration which changes over time and a curve of a frequency band ratio near a high order mechanical natural frequency of the instruction jerk which changes over time according to the instruction acceleration time-frequency graph and the instruction jerk time-frequency graph, thereby reflecting restraining ability of the numerical control system interpolation generation motion instruction for machine resonance. According to the dynamic precision oriented numerical control system interpolation generation motion instruction evaluation method, a relationship that changes over time between a frequency component and an amplitude value thereof can be obtained simultaneously.

Description

technical field [0001] The invention belongs to the technical field of numerical control machine tools, and in particular relates to a dynamic precision-oriented numerical control system interpolation generation motion command evaluation method. technical background [0002] As the brain of the machine tool, the CNC system is an important part of the CNC machine tool. The function of the CNC system is to interpolate the tool path of the part (expressed in NC code) to generate motion instructions for each axis of the machine tool. The servo feed system of each axis of the machine tool receives these The motion command drives the tool and the workpiece to move relative to each other to complete the part processing. [0003] In the case of high feed rate and large curvature tool path processing, the motion command generated by interpolation often contains more frequency components, which causes the machine tool to produce significant dynamic errors such as following error and m...

AI Technical Summary

Problems solved by technology

At present, the time domain analysis method alone can visually observe the change of the amplitude of the interpolation production motion command over time, but the frequency component in the motion command cannot be obtained; while the frequency domain analysis method alone is used to analyze the motion command generated by interpolation Only the frequency components in the entire motion command can be obtained, and the tool path position corresponding to the frequency components cannot be determined

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