Research On Small Underwater Dual-arm Manipulator Control System

With the continuous depletion of resources on the earth,the development of marine resources has attracted more and more attention.China has a vast sea area and abundant marine resources.In recent years,China has vigorously developed the marine economy and implemented the strategy of "prospering the sea with science and technology and managing the sea according to law." China's marine economy will enter a stable track of development.As the development of oil,natural gas and other resources gradually extends from the offshore to the deep sea,the demand for underwater robots continues to rise.As the main undertaker of underwater robots' operating functions,underwater manipulators have gradually attracted people's attention.Underwater operations such as installation of subsea pipelines,daily maintenance of drilling platforms,mining and investigation of subsea minerals,underwater manipulators are widely used.Compared with ordinary land-based manipulators,underwater manipulators have the following characteristics: due to the impact of the underwater environment and the ease of carrying on the underwater robots,the underwater manipulators are required to be miniaturized,convenient and flexible to operate,stable in control,and able to complete onshore-underwater signal transmission and control.In this paper,the following research is carried out in response to this requirement.First of all,this article by querying domestic and foreign relevant literature,according to project requirements for the overall design of small underwater manipulator,select the appropriate driving method,study the overall system composition of the manipulator,complete the configuration design of each part of the manipulator.Secondly,the kinematics model of the underwater manipulator is discussed.According to the main scale parameters of the mechanical design of each joint of the manipulator,the multi-degree-of-freedom manipulator Denavit-Hartenberg coordinate system is established.Through matrix transformation,the change matrix between the base of the manipulator and the end effector is obtained,and the forward motion model of the manipulator is established.At the same time,the inverse kinematics of the manipulator is solved.From the position of the end of the manipulator in the given Cartesian space,the joint angles in each joint space are mapped in reverse.Then,the overall plan of the control system is studied,the upper and lower computer control based on the linear topology CAN bus communication is selected as the control system plan,and the control system is designed from the three aspects of working principle,hardware and software.According to the PID control algorithm,combined with the threeloop control and interpolation smooth motion curve to control the joint module;the hardware is used to select the joint drive module and the sensor;the software uses the MVC architecture,using Qt,SQLite,Open GL and other tools to realize the visual interface Software processing.Finally,according to the designed underwater dual-arm manipulator control system,the small underwater dual-arm manipulator is tested step by step to verify the control performance and reliability of the small underwater dual-arm manipulator control system.This article combined with related project research,carried out a series of research work on small underwater manipulator control system,and its research results provide a certain theoretical basis and technical means for the design of underwater manipulator control system.