Performance Evaluation of an Underwater Remotely Operated Vehicle Based on Natural Frequency Analysis in Presence of Added Mass

Nowadays, the Underwater Remotely Operated Vehicle (ROV) has captivated the interest of researchers, given its widespread applications in both military and marine industries. However, establishing a standardized model for use in challenging conditions, such as the presence of added mass, poses a significant challenge. The ROV serves a crucial role in oceanographic research, contributing to data collection, image recording, and deep-sea surveys. The development of a standard model holds promise for enabling researchers to design ROVs suitable for diverse tasks across varying ocean depths. In this study, for the first time, propose a natural frequency analysis of an ROV, considering added mass. Additionally, conduct a strength analysis for the ROV under critical boundary conditions, including displacement in a dry environment and Stuck in the sludge of the sea. The natural frequency analysis of the underwater environment, considering the acoustic properties of water fluid, is performed using ABAQUS software. The natural frequency of an object in water, indicating the frequency of vibrations per second, depends on factors such as temperature, pressure, and density of the surrounding water. This analysis, integral to structural dynamics, provides valuable insights into how vibrations propagate, facilitating the design of more stable structures. Furthermore, the study investigates the effects of added mass on different vibration modes of the ROV in the MATLAB Environment. Stress analysis results demonstrate that the ROV, submerged in critical boundary conditions due to hydrostatic forces, drag, and equipment weight, possesses sufficient strength for movement in deep-sea environments. Natural frequency analysis in water reveals a reduction in the impact of surrounding fluid and added mass in high-frequency modes. To enhance evaluations of fluid dynamics around the structure, fluid dimensions are considered until the structure’s frequency and resulting frequencies converge. Simulation results using the acoustic properties of the fluid indicate that the fluid dimensions obtained are approximately five times that of the device underwater. Additionally, the results demonstrate a reduction in natural frequency by up to 45% due to the influence of added mass.