Research On Active Motion Compensation Technology Of Hydraulically Driven Three-DOF Gangway Device

With the continuous development of marine technology,human beings began to carry out complex offshore operations under various sea conditions.The irregular movement of ships in the marine environment has adversely affected the safety of offshore operations.At this time,active motion compensation technology can be greatly used to reduce the danger.The gangway is an important marine equipment that forms a stable sea passage between the installation mother ship and the land target,effectively compensating for the interference effect of the mother ship's motion under the interference of the waves on the end position of the gangway.It can better control the land distance to reduce the danger of work,and the land task is completed more quickly to improve the work efficiency.Therefore,the research on the active motion compensation technology for the gangway has important practical significance and engineering value.At present,the research on active motion compensation technology in China mainly focuses on the active heave compensation system,and there are few studies on motion compensation with multiple degrees of freedom.In this paper,the bridge device with active motion compensation technology is taken as the research object.After introducing the composition and working principle of the gangway system,the active motion compensation technology based on the four-degree-of-freedom interference motion of the mother ship is emphasized.An active motion compensation algorithm for the end position of the gangway is proposed.Firstly,the kinematics modeling of the gangway is carried out by using the D-H parameter method commonly used in robotics combined with the mother ship interference motion,and the spatial position of the end of the gangway after the interference of the mother ship motion is obtained by the kinematics positive solution.Secondly,according to the result is calculated by kinematics inverse solution to calculate the speed compensation amount of the gangway in three degrees of freedom: rotation,pitch and telescopic;then these three compensation quantities are converted into electrical signals and input into the control components of each hydraulic actuator to compensate for the spatial position of the end of the gangway.Then,the principle analysis and mathematical modeling of the three sets of hydraulic actuators in the gangway were carried out,and the transfer functions without considering the external load force and the external load torque were obtained,and the controller for each set of actuators is designed to improve the performance of the system.At the same time,the multi-degree-of-freedom active motion compensation controller is obtained by combining the kinematics inverse solution.Finally,the effectiveness of the proposed compensation algorithm is verified by Matlab/Simulink simulation,and the position of the end of the gangway before and after compensation of different actuators are compared,which can intuitively obtain the ideal compensation effect.In this paper,the multi-degree-of-freedom mother ship motion is used as the interference condition,and the active motion compensation technology is used to eliminate the interference target,so that the research problems and methods are closer to the actual situation.At the same time,the use of less degrees of freedom motion compensates for the complex mother ship motion impact,streamlines the design of the entire active motion compensation system,and reduces the development cost of the device,so it has important research value and broad application prospects.