The Design Of The Launching And Recovering Device On Workboat And The Optimization Of The Structure

The launching and recovering device of the workboat which is installed on the moth-er-ship is mainly used to launch and recover the function of the workboat. It is the prerequisitefor the rescue and scientific research on the sea to launch and recover the workboat and life-boat successfully. The normal operation of the launching and recovering device on workboatis directly related to the personal safety of the staff on the workboat. This article aims to studythe related technology of the launching and recovering device on workboat.Traditional launching and recovering device on workboat is installed on the edge of theboat, and the protective devices are fixed such as safety fence. But such installation tends tooccupy the installation space of other equipments. Meanwhile traditional launching and reco-vering device is too large and occupies too much space, in addition, it takes long a time tolaunch and recover the workboat because of the relatively high gravity.The current situation of the launching and recovering device on workboat at home andabroad is analyzed and summarized in this article; according to the requirement of this project,the overall design scheme of this device is presented. Folded structure is applied, the retracta-ble arm and the winch are installed separately so that the launching and recovering device onworkboat can be placed in the cabin, thus the space above the deck is saved and implicit in-stallment is realized. The height of C.G. of the entire launching and recovering device is lo-wered effectively thus the swing of the mother-ship is relieved. By controlling the two Hy-draulic cylinders which drive the retractable arm, the movement of the entire launching andrecovering device is controlled. The launching and recovering device adopts Manual hook bythe sailor so as to promote the security.The working space of the launching and recovering device, the speed of the end of the re-tractable arm, angular velocity and kinetic equations is achieved through the correlation cal-culation made on the launching and recovering device. The working space curve is achievedthrough analysis and verified by the ADAMS software. Through the working space curve, therange of movement and the work path of the launching and recovering device can be watcheddirectly while it is running regularly.Optimization analysis and modal analysis of the launching and recovering device are made.Through ANSYS software, the relationship between the thickness of the retractable arm, the interval of supporting steel plates inside the retractable arm, the number and the maximum ofthe stress on the retractable arm, the first natural frequency and the total mass is got, the op-timal thickness of the arm is obtained according to other requirements of the materials. Thefirst six natural frequency of the launching and recovering device is obtained through modalanalysis and parameters are offered to avoid resonance. Meanwhile the strength analysis ofthe retractable arm is made in order to improve security. ADAMS software is used for simula-tion experiment and check if interference exists in the launching and recovering device. Cor-relation calculation is made on the main parameters of the hydraulic cylinder. Through flex-ibility analysis, displacement at the end of the retractable arm is observed in the process ofmovement while the mother-ship is moving. The environment of the mother ship is changed,which means the swing angle of rolling and pitching of the mother-ship is widened, the dis-placement at the end of the retractable arm is measured while the retractable arm is contract-ing and the results are analyzed.