Overall Design And Power Positioning Of ROV For Underwater Inspection And Operation

Hydraulic buildings are affected by natural aging and natural disasters such as earthquakes,geology and floods,which can lead to cracks,collapses and other damages in dams,crossings and other hydraulic buildings.Underwater damage is generally not easy to find and has a great hidden nature,and at the same time,it has to withstand a certain amount of water pressure,which is a great safety hazard.For a long time,underwater inspection and repair operations of hydraulic buildings have been a complex technical problem.With the development of underwater robotics,underwater robots have gradually replaced manual underwater operations with many advantages such as high efficiency,easy operation,safety and reliability,and become a powerful assistant for regular maintenance of water conservancy and hydropower infrastructure.The ROV is connected to the surface support equipment by umbilical cable,and the operator controls the ROV by remote control from the mother ship or onshore.By using ROV as the underwater operation platform and carrying underwater manipulator,gimbal camera,cleaning and cutting device on it,underwater inspection and maintenance of hydraulic buildings can be realized precisely and efficiently.This paper firstly combines the specific engineering application requirements of ROV in underwater inspection and repair operations of hydraulic buildings,and completes the overall structural design through the optimal configuration of each component and the calculation of stable center height to ensure its underwater operation with good stability.Second,the dynamics of the ROV is modeled and reduced to a four-degree-of-freedom model,and the hydrodynamic calculation of the model is carried out by Fluent,and the information collected by the sensors is pre-processed by Kalman filtering to make the collected information more accurate and reliable and to improve the stability of the system.Finally,the fuzzy predictive control algorithm combining fuzzy control and model predictive control is used to simulate the dynamic positioning of the ROV,which is divided into the simulation of dynamic positioning in three single degrees of freedom: bow angle,transverse swing and constant depth,the simulation of dynamic positioning in X-Y plane and the simulation of dynamic positioning in X-Y-Z space.By setting different external environmental conditions and completing the numerical simulation of power positioning algorithm under each working condition,the power adjustment strategy and different power positioning performance of ROV are obtained,which enhances the adaptability of ROV in complex environment and the stability in underwater detection and operation,and improves the quality and efficiency of its underwater operation.