Research On The Compensation Of Viscous Pressure Characteristics And Variable Gain Control Of Deepwater Hydraulic Manipulator

The 11,000-m-deep Mariana Trench is rich in polymetallic gold mines,cobalt-rich mines and other precious resources.Not only that,it is also of great value in exploring the history of the earth as it lies at the deepest depth of the sea.As James Cameron dived into the Mariana Trench with Deep Sea Explorer,people realize the deepest depth of the sea.However,the deepest environmental conditions at the bottom of the sea are far more complicated than people think,especially on the hydraulic system.Therefore,the full deep sea environment conditions put forward higher requirements for the control system of hydraulic manipulator.In this paper,according to the characteristics of "high pressure and low temperature" in deep sea environment,the size of the groove corresponding to the O-ring in the cylinder used for the manipulator is redesigned.According to the relationship between the "viscosity-pressure relationship" and "viscosity-temperature relationship" of hydraulic oil,a manipulator control model suitable for deep sea environment is established.Using load sensing technology,a variable gain control algorithm suitable for the full deep sea hydraulic manipulator is proposed.The full paper is divided into six chapters:The first chapter introduces the research background of the dissertation,analyzes the influence of the "high pressure and low temperature" characteristics of the full deep sea environment on the manipulator control system,and analyzes the commonly used manipulator control algorithm,and puts forward the research significance and main contents of this dissertation.The second chapter analyzes the requirements of manipulator control system based on the"high pressure and low temperature" characteristics of deep sea environment from three aspects of hardware,software architecture and control algorithm,and focuses on the seawater depth and control system,pressure feedback and load calculation method.In the third chapter,according to the characteristics of "high pressure and low temperature"in deep sea environment,the corresponding pressure loss model of 11000 meters deep sea environment is established by using the relationship between viscosity and pressure and temperature.The classic model of valve controlled asymmetric cylinder is used to establish and analyze the manipulator single joint control model.Finally,the kinematics and dynamics model of manipulator is established by Lagrange energy methodIn the fourth chapter,the manipulator algorithm based on fixed gain is designed by establishing and analyzing the static load model of manipulator.By analyzing the dynamic load of the manipulator,the load of the manipulator changes greatly,but the corresponding dynamic load model can be established by the dynamics model of the manipulator.Based on the dynamic load model,the load sensing hydraulic manipulator control algorithm based on the variable gain is designed.In the fifth chapter,the manipulator model is used to carry out the simulation analysis.Based on the experimental platform of laboratory manipulator,the LAB VIEW interface is used to simulate the function of the host computer,and the experimental data of the manipulator's gripper with unknown heavy load and the known comparative data are respectively obtained.Finally,the simulation and experimental data verify the effectiveness of the load-sensing manipulator control method based on variable gain.The sixth chapter summarizes the main contents of this thesis,points out the innovation points at the same time to put forward the improvement method according to the shortcoming of the paper.