Identification strategy of error parameter in volumetric error compensation of machine tool based on laser tracker measurements

This paper presents a new method for volumetric verification of machine tools. Beyond the consideration of a particular machine, a general verification methodology is presented based on the type of machine to verify the number and movement of axes and different techniques that can be used.A scheme and kinematic model with the inclusion of the measurement system depending on the kinematics of the machine are presented. The model describes the geometry and kinematics of a real milling machine based on a parametric synthetic data generator, which generates a test with known geometric errors and noise to enable a study of different optimisation techniques and models.Similarly, different errors identification techniques and volumetric verification models are presented and analysed.The paper shows the improvement that occurs in verification by considering optimisation phases, the appropriateness of using new techniques of feedback, and the influence of optimisation parameters. Chebyshev polynomials and its characteristics are presented, as well as a regression function for the new verification model. The new developed technique allows the characterisation of the different errors in the whole workspace of the machine and in less time than direct verification methods.

► General volumetric verification methodology.
► Kinematic model with the inclusion of the measurement system.
► Parametric synthetic data generator.
► Obtaining and compensating errors through Chebyshev polynomials.
► Influence of new techniques and optimisation parameters in volumetric verification.