Model-Based Dynamic Structural Modification of Machine Tools

Mateusz Wąsik,Krzysztof Lehrich,Krzysztof Lis,Łukasz Mucha

doi:10.1155/2018/3469171

Abstract

The article proposes modification of machine tool structures methodology on the example of a body of vertical milling centre stand. It is based on the results of experimental research and allows for the prediction of dynamic features of individual bodies and complete structures on the basis of the described modal model. It takes into account the possibility of mass change at the model node and the introduction of additional rigidity and damping by a combination of selected nodes of the model. The methodology can be applied in the case of machine tools in which the loss of stability has been found during its maintenance, what consequently disables the possibility of machining with the required machining parameters from the performance point of view. Modal parameters modification is based on structural dynamic modification techniques and preliminary simulation tests performed by using Finite Element Method (FEM) and verification with experimental research.

Highlights

The dynamic properties of machine tools have a very significant impact on the process of cutting and are considered among the most important features of the assessment of the machine construction
For this purpose, Finite Element Analysis (FEA) and a virtual model can be used, which is the base of the development of construction documentation
Finite Element Method (FEM) application does not give a full and accurate description of the dynamic properties of the machine structure, which is a result of multiple contact connections in guiding systems and between individual bodies of the machine that are often not considered in FEM simulations [3,4,5,6]

Summary

Introduction

The dynamic properties of machine tools have a very significant impact on the process of cutting and are considered among the most important features of the assessment of the machine construction. It is reasonable to analyse the dynamic properties of machine tools experimentally (e.g., by carrying out an experimental modal analysis) In this case, a physical model is required. The article proposes modification of machine tool structures methodology It is based on the results of experimental research and allows for the prediction of dynamic features of individual bodies and complete structures on the basis of the described modal model. It takes into account the possibility of mass change at the model node and the introduction of additional rigidity and damping by a combination of selected nodes of the model

Materials and Methods

Results and Discussion

Mode 5th