Research On The Executive Mechanism And Hydraulic System For AUV Multi-Size Adaptive Docking And Release System

With the continuous development of ocean science and technology,autonomous underwater vehicle(AUV)have been widely used in marine resource exploration,underwater operations,marine environmental monitoring,and other fields.When executing tasks,AUV need to repeatedly perform underwater operations and observations,so efficient release and recovery are necessary to ensure their operational efficiency.Currently,there have been many studies on AUV surface and underwater release and recovery technologies both domestically and internationally.However,surface release and recovery require a lot of manpower and resources.Therefore,underwater release and recovery can improve efficiency,but most of the underwater release and recovery methods only meet the needs of specific sizes and structures of AUV and cannot achieve fast deployment and recovery of multiple sizes of conventional AUV.Therefore,researching the release and recovery device that can adapt to AUV of multiple sizes and realizing rapid release and recovery is of great significance for improving the operational efficiency and flexibility of AUV and has important application prospects and scientific research value.The main research content of this paper is as follows:Based on the analysis of research achievements of domestic and foreign underwater release and recovery systems adaptable to AUV of multiple sizes,this paper analyzes and summarizes the functional requirements of the release and recovery system.Addressing the problem of recovering AUV of multiple sizes,this paper carries out a scheme demonstration of an adaptive release device and compares the variable diameter guiding hood release scheme,the guiding hood limited-position release scheme,and the box-cage release scheme.The analysis considers the number of actuators,the complexity of the mechanism,and the difficulty of recovery,and ultimately selects the box-cage release scheme.This paper studies the driving and control methods of AUV recovery device,and uses a hydraulic system as the driving scheme of this paper.This paper analyzes the characteristics of the gripping mechanism and compares its schemes,ultimately selecting the hand claw gripping scheme.The force and motion analysis of the hand claw grip is carried out to determine the required force size and stroke of the grip for corresponding sized AUV,and analyze the strength of the hand claw.To address the guidance issue of the second cylinder,the hydraulic cylinder guide rod is designed and its strength is analyzed,followed by design of the guiding platform and the box-cage.The hydraulic circuit is then designed,and relevant components are designed and selected.The hydraulic cylinder with an embedded magnetostrictive displacement sensor and the rope sensor is then individually designed.Considering the use of a stacked valve hydraulic compartment and an inserted valve hydraulic compartment,the latter is ultimately selected as it has higher modularity.The hydraulic system pressure compensation is studied,and the hydraulic oil tank and compensator are integrated on the oil bladder and detailed design is carried out.This paper studies the hydraulic system control scheme of the AUV adaptive release and recovery device and designs the layout of the hydraulic compartment.Basic tests are carried out for pressure and displacement sensors,and an onshore system debugging platform is established,which includes calibration tests for the proportional directional valve and the proportional overflow valve and an onshore test of the adaptive gripping mechanism is carried out to verify the feasibility of the gripping claw proposed in this paper.