| Pipeline transportation is commonly used to efficiently transport resources,but its complex working environment makes it vulnerable to issues such as corrosion and sedimentation due to the influence of fluids and external factors.Especially for buried pipelines,it is difficult to detect and maintain.And pipeline robots can better solve this problem,replacing manual work to complete internal pipeline operations.This article designs a variable diameter fluid driven pipeline robot with constant speed movement to address the problem of in pipe operations in long-distance transportation pipelines.Firstly,conduct a feasibility study to analyze the robot’s circumferential rotation angle in the pipeline and the connection between the unit bodies,and determine the constraints on the overall size parameters of the robot.Suggest two fluid energy conversion mechanisms,compare their advantages and disadvantages,determine the umbrella type energy conversion mechanism as the driving mechanism,design a support mechanism and an active passive variable diameter mechanism based on overall size constraints,complete the robot structure scheme,and establish a three-dimensional model of the pipeline robot,laying the foundation for subsequent research.Analyze the force situation during the movement of pipeline robots based on the characteristics of their working environment,and theoretically calculate the driving force and resistance.The motion mechanics equations of the robot in straight and curved pipelines are established,and curves are drawn based on the motion mechanics equations to theoretically predict the robot’s motion characteristics.Carry out statics analysis on the main load-bearing components,carry out static characteristic analysis and modal characteristic analysis simulation experiments in Ansys,and verify the mechanical structure rationality of key components;Based on Adams,kinematics simulation experiments were carried out to study the trafficability and motion characteristics of the robot in straight pipes,90 ° curved pipes,short distance obstacle pipes,and variable diameter pipes.Finally,design the overall control system scheme and select the appropriate hardware system based on the characteristics of the robot’s working environment.The Grubbs criterion was used to eliminate sensor errors and the speed value was obtained through data fusion using a weighted method.A fuzzy PID control algorithm was proposed based on adaptive control ideas,and joint simulation experiments were conducted in Matlab and Adams,Verify the effectiveness and superiority of the algorithm in speed control of pipeline robots. |
