Design And Research Of Hybrid Structure Shipbuilding Crane Manipulator

The shipbuilding industry is a comprehensive industry that provides strategic technical support and equipment support for maritime transportation,marine development and national defense construction,and has a strong leading role in the development of key industries such as petrochemicals,equipment manufacturing,electronic information,and steel.The level of ship construction is an important indicator of a country’s marine economic development and maritime international status.Among them,the segmented hoisting process is one of the important links in the ship repair and construction process,accounting for about 45% of the total ship construction workload.However,the existing hoisting cranes are mostly portal cranes with a single-DOF（Degree-of-Freedom）structure.Due to their own structural limitations,it is difficult to output flexible working trajectories.The shipbuilding requirements can only be met by increasing the size,and there are also manufacturing high cost,high processing and assembly process requirements,difficult maintenance and other shortcomings.In order to solve the above problems,the multi-DOF controllable mechanism with a hybrid structure is applied to the research of shipbuilding crane manipulators,and a new category of hybrid structure shipbuilding crane manipulator is designed,which has the advantages of flexible output and high operating efficiency.Related work and innovations are as follows:The functional analysis method is used to analyze the topological structure,input and output laws of the traditional portal crane actuator and its end-effector action requirements;combined with the engineering practice of typical shipbuilding lifting and transportation operations such as hoisting,lifting,small erection,large erection,etc.Based on the method of inserting binary vertices to contracted graph,the type synthesis problem of the hybrid mechanism for shipbuilding is studied;the fuzzy evaluation method is adopted to optimize the selection of the synthesized mechanism,and a series of hybrid shipbuilding crane types are obtained.Using the displacement manifold method and the position and orientation characteristics theory（POC set）,the motion output law of a 9-bar and 11-pair crane manipulator was analyzed,and the coupling degree of the hybrid shipbuilding crane manipulator was solved.Combining with the requirements of realizing the typical output actions of shipbuilding cranes,the closed-loop vector method and constraint equations are used to develop a mathematical analysis model of mechanism kinematics,and the position,velocity,acceleration and other motions of the mechanism when completing a given hoisting task are solved through vector operations.The law of learning and the mapping relationship between the kinematics output parameters of the end-effector and each input variable;In view of the structural characteristics of this type of mechanism,combined with the realization of the process requirements of large assembly hoisting,group vertical hoisting and closing,the matrix method and line are used.Geometric method,studied the singularity of the mechanism,working space boundary conditions,theoretically reachable working space and effective working space under actual working conditions;Spline interpolation method was used to optimize the crane structure’s typical hoisting operation trajectory.Based on the velocity Jacobian matrix,the load-bearing capacity and dexterity are analyzed,and on this basis,the mechanical properties of the new mechanism hoisting components under different regular wind loads are analyzed.Through the dynamic-static method to develop the dynamic statics model,obtaining each hinge constraint force and moment balance of active components,using Lagrange method to develop its rigid body dynamics model,active rod system generalized force is obtained and its change law of parameters,such as the optimization design and synthesis of for institutions and provides the reference for the forecast of motor parameters;The stiffness characteristic model of the mechanism was developed,and the relationship and influence of the stiffness mapping and kinematics and dynamics parameters of the mechanism during lifting operation were discussed,and the stiffness performance of the ship repair task was studied.Using three-dimensional simulation software to carry out computer modeling and simulation analysis on the proposed novel shipbuilding crane actuator,and carrying out related simulation analysis in combination with the actual hoisting operating conditions of the shipbuilding crane,verifying the feasibility and theory of the application of this new type of mechanism in the field of ship repair and construction the correctness of the analysis.Relevant research results can also provide a good reference for the innovative design of various oil and gas drilling platforms,transportation and packing ships,deck machinery and other ships and marine engineering equipment.