# Enhancing Vibration Analysis in Hydraulic Presses: A Case Study Evaluation
## 1 Introduction
This capability is particularly useful for analyzing complex structures with intricate geometries or for investigating vibrations that propagate through the thickness of materials [11]. Non-destructive vibration testing is a pivotal aspect of structural health monitoring, crucial for assessing structural integrity and mitigating risks associated with structural performance deficiencies [12]. Among the array of vibration testing methods, ambient vibration testing stands out as the most cost-effective and widely utilized technique for evaluating a structure's physical condition during operational service. Leveraging ambient vibration data, modal identification serves as a valuable tool for informing model updates and detecting damage throughout a structure's lifespan. Extensive research has demonstrated the efficacy of modal identification in probing the dynamic behavior of diverse structural typologies. Modal identification executes using a Fast Bayesian FFT method, chosen for its capacity to determine modal parameters with probabilistic precision while analytically assessing associated uncertainties--a critical consideration in field vibration testing scenarios marked by factors such as measurement noise, sensor misalignment, and modeling discrepancies. This article focuses on the utilization of such an advanced measurement system for vibration monitoring in hydraulic presses. The system comprises a three-axis accelerometer, a data acquisition unit, and dedicated measurement software. Through a detailed case study analysis, the configuration of the measurement system was examined, including the selection of sensor placement and sampling frequency, to optimize the measurement process. Furthermore, the effectiveness of vibration monitoring in hydraulic presses through practical experimentation and data analysis was evaluated. By comparing measured vibration levels to established thresholds and conducting a frequency domain analysis, the aim of this research was to identify patterns and trends indicative of the press's operational condition. Additionally, the impact of production parameters on vibration levels was investigated, and we explored how vibration monitoring can contribute to process optimization and maintenance planning. Overall, this article underscores the importance of vibration monitoring in hydraulic presses and highlights the capabilities of advanced measurement systems in providing valuable insights into machine performance and health. By leveraging such technology, manufacturers can enhance productivity, minimize downtime, and ensure the longevity of their hydraulic press equipment. The novelty of the research lies in the comprehensive exploration and application of cutting-edge measurement technologies for vibration monitoring in hydraulic presses that work in real-time (online). That means vibration data are collected and analyzed immediately after vibrations occur. Unlike traditional methods where measurements can be performed periodically or after the machine has finished operating, real-time monitoring allows one to quickly identify even subtle changes in vibrations, which may indicate potential mechanical problems, failures, or changes in production parameters. The structure of the paper is as follows. In Section 2, an overview of the current state of the art in the field of vibration monitoring in industrial machines, with a specific focus on hydraulic presses, is described. Section 3 outlines the characteristics of the proposed measuring system. In Section 4, the measurement method, including experimental procedures and signal analysis, is detailed. Furthermore, in the same section, the experimental results obtained from our study are presented. Section 6 concludes the paper, summarizing the main objectives and discussing potential directions for future technology development.