A Kinematic Model for Volumetric Error Estimation of a Special Purpose CNC Machine

Abstract:

This research reports on error identification and compensation of a special purpose CNC machine. The kinematic model of the machine was developed using rigid body kinematics and small angle approximation of the axes of the machine through homogenous transform matrices, and the equations describing the volumetric errors. The machine was calibrated to measure the axes errors, which were used in the kinematic model in order to determine compensation values. The model was evaluated by means of direct measurements of axis movements using a laser interferometer, as well as in cutting tests, where a large number of holes were drilled in plates and measured with a CMM. The results showed that the developed model achieved an average error reduction of 40%, for the X and Y axes.

• Periodical: Applied Mechanics and Materials (Volume 232)
• Pages: 367-371
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.232.367
• Online since: November 2012
• Authors: M. Simpson, I.A. Gorlach
• Keywords: CNC Machine, Geometric Accuracy, Modeling

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