Research On Design And Control Of Robotic Arm For Petrochemical Inspection Operations

In the petrochemical industry,it is very important to inspect the status of equipment such as pipelines,storage tanks and reactors.However,the on-site environment is usually harsh or even dangerous.If robotic arms and related devices are used instead of manual inspections,the safety of personnel will be improved.This paper designs a robotic arm and improves a control algorithm to ensure that the robotic arm can perform high-precision and repeatable movements.In order to verify the effectiveness of the method,a point-to-point fixed-point detection task was simulated in a petrochemical environment with a load of 5kg at the end of the robotic arm,and experiments were carried out.The results show that the robotic arm can perform inspection tasks efficiently and can operate stably in narrow and complex spaces.The specific content is as follows:1.According to the idea of integrated and modular design,combined with the chemical environment and the application of the manipulator,the design indicators were formulated,and the structural shape of the manipulator was designed using SOLIDWORKS software,including servo motors,reducers,brakes,etc.,and obtained through model selection calculations The specific model of each part.On this basis,ANSYS software is used to conduct topology optimization analysis on key stressbearing parts such as the manipulator shell,so as to achieve the purpose of lightweight design.2.Research on the kinematics model of the manipulator.On the basis of the threedimensional model of the manipulator,the mathematical model is established according to the DH parameter method,the forward and reverse kinematic equations are deduced,and the singular position is obtained by solving them.Use the Lagrangian method to construct the dynamic model of the robotic arm,and analyze the kinetic energy and potential energy of the system during the movement process;according to the planned trajectory formed by the kinematic equation,import the motion curve of its joint angle into ADAMS for virtual prototype simulation and analysis The torque variation curves of each joint provide theoretical support for the next trajectory tracking control.3.Research on the trajectory tracking control of the manipulator.On the basis of dynamic analysis,aiming at the problem of the decrease of control accuracy caused by the modeling error in the trajectory tracking control of the manipulator and the undetermined interference factors of the chemical environment,a sliding mode control based on RBF neural network switching gain adjustment is improved.The algorithm uses the self-adaptive ability of the neural network to learn the upper bound of the uncertain part of the control system adaptively,and uses its output as the dynamic compensation item of the sliding mode control.The proposed improved algorithm is simulated in MATLAB-SIMULINK,and the trajectory planned by kinematics is tracked.The analysis results show that the improved algorithm can better eliminate the influence of the external uncertain part on the actual trajectory tracking,and can better reduce the chattering at the sliding mode switching surface in the sliding mode control system,achieving a relatively Good tracking performance.4.Finally,build an experimental platform to simulate the trajectory of the robotic arm during inspection operations.Experiments show that the mechanical arm has a reasonable structural design,dexterous movement,and smooth track operation without large vibrations;the feedback data from the laser tracker shows that the working error of the robotic arm is within 0.3mm,and it has reliable working performance.