Research On Ship Motion Simulation And Mechanical Arm Lifting Motion Compensation Control

As an important equipment for cargo transshipment and Marine construction,Marine lifting manipulator is affected by severe sea environment,such as wind and waves,and its terminal will have problems such as misalignment of positioning and load sway,which greatly affect the efficiency and safety of offshore operations.This article as a starting point,combining university-enterprise cooperation project "sea logistics equipment intelligent control platform"(No.2016-WS301),built in the laboratory environment offshore Marine lifting condition simulation and motion compensation of the robotic arm platform,and the working condition of ship motion simulation with the compensation control of mechanical arm lifting of further research.Firstly,this paper uses a six-degree-of-freedom parallel platform as the simulation platform for ship motion conditions,and converts the six-axis industrial manipulator into a lifting robot arm.The design and construction of the working condition simulation and motion compensation platform for the lifting robot arm are designed and built.Secondly,the wave spectrum and the ship motion model are established.The motion signal of the wave motion condition simulation is generated through simulation.And The kinematics modeling of the ship motion simulation platform is carried out.In the control method of electric cylinder,the position control algorithm of PID and feedforward compensation PID is proposed,and the advantages of feedforward compensation PID algorithm in tracking performance are analyzed.Then,the global world coordinate system of the whole system platform is established,and the homogeneous transformation of each coordinate system is used to describe the changes of terminal velocity and acceleration of the hoisting mechanical arm induced by the platform excitation in the working condition simulation under the global coordinate system.Based on inverse kinematics,a compensation control algorithm for the end position of the lifting manipulator is proposed.The simulation model is built by Matlab to verify the correctness of the compensation algorithm.Finally,based on Visual Studio 2013,coding C++ program in this paper,designed the software of system motion control with the idea of hierarchical design,and completed theprogramming realization of control strategy,data communication,servo driver and other modules.By sea condition simulation and mechanical arm lifting mechanical arm motion compensation control of the experimental results show that the feedforward PID control algorithm on the follow performance of the platform motion than ordinary PID increased by20.47%,while in three directions at the end of the lifting arm compensation effect is obvious,static compensation of about 12 mm,the average error dynamic compensation is about 23 mm,the average error motion control strategy is verified and the rationality of the compensation control algorithm is effective.