Aspects of the Investigation of the Dynamic Behaviour of Machine Tools by Operational Modal Analysis

Berthold, Jan; Kolouch, Martin; Wittstock, Volker; Pütz, Matthias

doi:10.17973/mmsj.2017_12_201777

Cited by 3 publications

(2 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…(1) Modal analysis theory The modal of cab structure is one of the inherent properties of cab, which characterizes the vibration of cab structure under external excitation. With the help of modal analysis theory, the frequency and mode shape of each mode of the cab structure are studied, which can be used to avoid the resonance between the cab and the structure excitation [9][10]. In addition, cab structural modes are closely related to cab acoustic analysis.…”

Section: Structural Modal Analysis Of the Cabmentioning

confidence: 99%

Sound Field Optimization of Construction Machinery Cab Structure based on Ergonomics and Mathematical Modeling

2021

KME

View full text Add to dashboard Cite

The continuous progress of science and technology drives the development of domestic construction machinery. Now the emergence of high-power construction machinery, at the same time also brings more and more prominent noise problem, now people pay more and more attention to the noise problem of construction machinery. This paper mainly studies the sound field optimization of construction machinery cab structure based on ergonomics and mathematical modeling. In this paper, firstly, the body structure model and the cab sound chamber model are preprocessed, and the free mode and sound solid coupling mode of the locomotive body structure and cab sound chamber model are calculated and analyzed respectively. According to the analysis results of cab acoustic package, the noise contribution degree is calculated to determine the ceiling and left component with the largest contribution. The acoustic package of the rear coaming and rear coaming is optimized.

show abstract

Section: Structural Modal Analysis Of the Cabmentioning

confidence: 99%

Sound Field Optimization of Construction Machinery Cab Structure based on Ergonomics and Mathematical Modeling

2021

KME

View full text Add to dashboard Cite

show abstract

“…The damping values are lower in the CFDD (over 180 Hz in the range from 0.2 to 0.6 %), also lower than in EMA, which is in contrast to the presumption, that the process damping leads to higher values. When comparing the mode shapes of the results by the MAC [Allemang 2003], there occurring some similarities but also differences, although the differences in techniques is not that different. Especially EFDD and CFDD differ in mode shapes, 6 out of 15 mode shape parings have a MAC higher 80 %.…”

Section: Frequency Domainmentioning

confidence: 99%

Investigation of the Dynamic Behavior of Machine Tools During Cutting by Operational Modal Analysis

Berthold¹,

Kolouch²,

Regel³

et al. 2019

MM SJ

View full text Add to dashboard Cite

A common approach for the experimentally estimation of modal parameters is the Experimental Modal Analysis (EMA). EMA takes place in the standstill of the machine, consequently neglecting effects that only occur during the cutting process. Alternatively the Operational Modal Analysis (OMA) makes possible to investigate structures under operational loads and conditions. In this paper, a machine tool is investigated during cutting and the modal parameters are estimated by OMA, with several identification methods working in the frequency domain as well as in the time domain. These results are also contrasted to EMA to investigate the differences between cutting and standstill.

show abstract

Identification of natural frequencies of machine tools during milling: comparison of the experimental modal analysis and the operational modal analysis

Berthold,

Kolouch,

Regel

et al. 2024

Prod. Eng. Res. Devel.

View full text Add to dashboard Cite

Modal parameters (natural frequencies, mode shapes and modal damping) help to understand the dynamic behaviour of complex systems like machine tools. There are several approaches for finding the modal parameters. The Experimental Modal Analysis (EMA) has proven to be effective at standstill of a machine tool. The excitation, realized with impulse hammer or shaker, and excited responses at several locations are measured. Alternatively, the Operational Modal Analysis (OMA) can be deployed for finding the modal parameters during operation. Here, responses to excitation resulting from operation are only measured. The modal parameters are mathematically identified from the measured signals in both cases but with different methods. This paper discusses, to what extent both approaches (EMA and OMA) can lead to plausible identification of natural frequencies of a machine tool during milling. Concerning the EMA, attention is paid to capturing the excitation. Process forces can be assumed to be the most significant excitation. However, there are other excitation sources beside the process forces (e.g. drives, hydraulic and pneumatic aggregates), which are considered by this assumption to be a part of disturbances with consequence for the identification of the modal parameters. Regarding the OMA, attention is paid to the fact that the excitation is assumed to be broadband like the white noise. Unfortunately, this assumption does not match the characteristics of a real excitation. This paper contains the identification of natural frequencies of a machine tool during milling within both approaches. The achieved results are compared and discussed.

show abstract

Aspects of the Investigation of the Dynamic Behaviour of Machine Tools by Operational Modal Analysis

Cited by 3 publications

References 0 publications

Sound Field Optimization of Construction Machinery Cab Structure based on Ergonomics and Mathematical Modeling

Sound Field Optimization of Construction Machinery Cab Structure based on Ergonomics and Mathematical Modeling

Investigation of the Dynamic Behavior of Machine Tools During Cutting by Operational Modal Analysis

Identification of natural frequencies of machine tools during milling: comparison of the experimental modal analysis and the operational modal analysis

Contact Info

Product

Resources

About