P. Szalai

56801793500

Publications - 7

Analysis and Measurement of Bending Stiffness of Wound String According to Higher Order Frequencies

Publication Name: Advances in Transdisciplinary Engineering

Publication Date: 2024-01-01

Volume: 59

Issue: Unknown

Page Range: 263-268

Description:

Bass strings of piano are manufactured by winding a wire around a core string. At these strings, the bending stiffness is not negligible. This effect modifies the higher harmonics of the string compared to the harmonic spectrum of the ideal string. This inharmonicity is even more significant in upright pianos. The effect has recently received renewed attention in the literature. In the present paper, the authors present a dynamic measurement for determining the bending stiffness of the piano strings. By using the so-called inharmonicity coefficient, the spectrum of the string is predicted, and the deviation from the ideal string is determined.

Open Access: Yes

DOI: 10.3233/ATDE240554

INVESTIGATION OF TRAFFIC INDUCED DYNAMIC RESPONSE OF A BRIDGE

Publication Name: Strojnicky Casopis

Publication Date: 2023-05-01

Volume: 73

Issue: 1

Page Range: 85-102

Description:

Bridges are special structures that provide a transport connection between areas divided by a physical barrier. Vehicles passing over bridges cause vibrations in the structural elements of the bridge, which can damage these structural elements over time. The aim of our research was to investigate the vibrations generated by vehicles on Hungary's first steel girder welded bridge, which was subjected to the maximum allowable load. In this paper, we describe the measurements we have carried out, analyse the results, present the vehicle-bridge interaction model we have constructed and the computer simulation we have carried out by using it. Our research results are intended to contribute to accident prevention and the safe operation of bridges.

Open Access: Yes

DOI: 10.2478/scjme-2023-0007

Parameter identification of a fire truck suspension for vibration analysis

Publication Name: Pollack Periodica

Publication Date: 2019-01-01

Volume: 14

Issue: 3

Page Range: 51-62

Description:

In case of field measurement it is essential to determine the measurement conditions. With accurate parameter identification credible measurement and simulation results can be achieved. In this paper the parameter identification of a CSD-755-10 heavy-duty fire truck suspension for vibration analysis is presented, which is an important base-point for further research.

Open Access: Yes

DOI: 10.1556/606.2019.14.3.6

Bending stiffness measurement of wounded piano strings

Publication Name: Proceedings of ISMA 2016 International Conference on Noise and Vibration Engineering and Usd2016 International Conference on Uncertainty in Structural Dynamics

Publication Date: 2016-01-01

Volume: Unknown

Issue: Unknown

Page Range: 2233-2240

Description:

Bass notes of pianos exhibit high degree of inharmonicity that means that frequencies of overtones depart from integer multiples of the fundamental frequency. Small amount of inharmonicity is tolerable for musicians and listeners, but higher ones cause unpleasant metallic tone. Reducing inharmonicity the first step is to investigate all influencing factors. This paper deals with effects of bending stiffness and nonuniform winding of wounded strings. As there is no reliable information in literature on bending stiffness data, a measuring procedure has been elaborated that is based on analysis of frequencies of overtones and the mathematical model of a vibrating string. Gained bending stiffness data opens the door to further quantitative investigations to reduce inharmonicity and improve sound generation methods of digital pianos.

Open Access: Yes

DOI: DOI not available

Determination of Measurement Parameters for Vibration Analysis by Bus

Publication Name: Strojnicky Casopis

Publication Date: 2022-11-01

Volume: 72

Issue: 2

Page Range: 189-200

Description:

From the point of view of field examinations, especially in the case of measurements done by instruments, it is crucially important to determine measurement conditions. Accurate identification of parameters enables accurate and certified measurement results to be achieved. In our work, we represent the determination of measurement conditions for harmful vibrations occurring during urban road transport of an Ikarus 55 type long-haul bus. This is a favourable basis for further vibration analysis regarding other buses.

Open Access: Yes

DOI: 10.2478/scjme-2022-0028

Vibration Spectrum of an Act-and-Wait Controlled System With Significant Damping

Publication Name: Iet Control Theory and Applications

Publication Date: 2026-01-01

Volume: 20

Issue: 1

Page Range: Unknown

Description:

Act-and-wait concept in control theory is a tool for enhancing the control quality by decreasing the destabilising effect of time delay. As was shown in other works, applying the act-and-wait concept to a PD position control increases the available range of proportional gains, which reduces the steady-state error of dry friction. In this paper, we focus on the vibration phenomena at the boundaries of the dynamic stability from the aspect of the vibration spectrum. We consider a single-degree-of-freedom mechanical model of DC actuators that contains significant effective damping. At different types of stability limits, new analytical and semi-analytical results are derived for the vibration spectrum. The results are validated by numerical calculations and experiments on a linear DC actuator.

Open Access: Yes

DOI: 10.1049/cth2.70111

Compensation of inharmonicity of piano strings with added masses

Publication Name: Journal of Physics Conference Series

Publication Date: 2026-01-01

Volume: 3190

Issue: 1

Page Range: Unknown

Description:

Bass strings of piano consists of a core string and a wire wound around the core. Although this construction is essential for creating strings with low frequency in the presence of moderate tension force, the increased bending stiffness shifts the overtones of the strings. This inharmonicity is more significant for upright pianos with shorter string lengths. In the literature, we can find conceptual ideas for compensation of this effect that is considered acoustically unpleasant. In the present research, we analyse the effect of adding concentrated masses to reduce the amount of inharmonicity. We focus on improvements in the acoustically most significant overtones. The proper parameters are found by using both a finite-element method and experiments.

Open Access: Yes

DOI: 10.1088/1742-6596/3190/1/012002