# Enhancing Vibration Analysis in Hydraulic Presses: A Case Study Evaluation
## 1 Introduction  
Contemporary machines and devices represent complex dynamic systems both in terms of functionality and construction, as well as spatially. The process of their manufacturing and operation consumes vast amounts of labor, materials, and energy. The rapid increase in requirements regarding the technical parameters of machines and devices, coupled with the simultaneous pursuit of reducing manufacturing and operation costs, has brought about fundamental transformations in design methods, production control, and operations. Numerous random damages, unexpected failures, and issues related to damages caused by life and aging processes justify the need for vibration research, which serves as a fundamental source of information about the changing condition [1; 2; 3; 4]. Hydraulic presses play a critical role in various industrial applications, ranging from metal forming to plastic molding [5]. These machines are subjected to dynamic forces and vibrations during operation, which can affect their performance, reliability, and longevity. Monitoring these vibrations is essential for ensuring the optimal functioning of hydraulic presses and for detecting any potential mechanical issues that may arise [6]. In recent years, advancements in measurement technology have provided engineers with sophisticated tools for accurately capturing and analyzing vibrations in hydraulic presses. One such technology is the use of advanced measurement systems equipped with accelerometers and data acquisition capabilities. These systems offer the precise monitoring of vibrations in multiple axes, allowing for a comprehensive assessment of the press's structural integrity and operational efficiency [7; 8]. Conventional vibration measurements are limited by the placement of only a limited number of sensors. However, with the advent of computing power and digital imaging technology, the emergence of 3D digital image correlation (DIC) methods has revolutionized the analysis of structural dynamics [9]. By enabling the full-field measurement ofstructural responses, DIC facilitates the simultaneous acquisition of a comprehensive data set. The results obtained using the DIC technique are compared with measurements of a conventional accelerometer and scanning laser vibrometer and with the finite element model. Strong correlations can be seen between all three finite element approaches, thus confirming the effectiveness of the DIC method in capturing full-field vibration phenomena. One of the novel vibration measurement methods is three-dimensional (3D) continuously scanning laser Doppler vibrometry (CSLDV) [10]. This system represents a cutting-edge technology in the field of structural dynamics analysis. This advanced system employs laser Doppler vibrometry (LDV) principles to precisely measure vibrations across three dimensions, providing comprehensive insights into the dynamic behaviors of structures. The CSLDV system operates by emitting a laser beam onto the surface of the target structure. This laser beam interacts with the surface, and the reflected light is collected by the system's optical components. By analyzing the Doppler shift in the frequency of the reflected light caused by the motion of the surface, the CSLDV system accurately detects and measures the vibrations of the structure. What sets the CSLDV system apart is its capability for continuous scanning. Unlike traditional vibrometers that measure vibrations at discrete points, the CSLDV system dynamically scans the entire surface of the structure, capturing vibrations across the entirety of the scanned area. This enables the system to provide a comprehensive spatial map of vibrations, offering detailed information about mode shapes, frequencies, and amplitudes across the structure. Furthermore, the CSLDV system operates in three dimensions, meaning it can measure vibrations not only along the surface of the structure but also in the depth direction.