Analysis and compensation of vibrations between tool and workpiece with non-linear methods

The use of metal cutting operations to manufacture shining surfaces, is an important area of high-precision engineering. Consequently, the machines used in such operations are required to meet increasingly exacting requirements. The effects of non-linearity can no longer be ignored. In the field of precision turning, vibration problems may occur which cannot be evaluated using standard algorithms. The dynamic displacement between workpiece and tool can contain signal elements with a non-linear character. Until now, the degree of modelling which has taken place on the basis of nonlinear methods and approaches, has been insufficiently high. Non-linear algorithms permitting real-time compensation for dynamic disturbances are, therefore, presented here. A modified Piezo unit will be used, in order to ensure resistance to the high machining forces which can occur in steel-machining operations. Machine tests show that the surface quality can be increased considerably when non-linear algorith ms are applied. The work presented here, is funded by the Volkswagen Foundation and the German Federal Department of Science, Education, Research and Technology (reference Number 13N3187).