Structural Design And Dynamics Characteristics Of Pipeline Inspection Robot For Ships

The pipeline inspection robot is a mechatronic device that can walk inside the pipeline and cooperate with other equipment to detect the inside of the pipeline and feed back the test results to the outside world.Pipeline inspection robots work in a variety of environments,such as straight pipes,elbows,reducers,U-tubes,T-tubes,etc,and there are often obstacles in the pipeline.The key for pipeline detection robot to adapt to such a variety of environments lies in its walking mode and changing path mode.The current pipeline inspection robots have problems such as complicated mechanical structure,weak variable diameter capability,and insufficient obstacle resistance.In view of these problems and the working environment of the robot,this paper have studied the two types of pipeline detection robots,both wheeled and crawler,in order to select a relatively better one,and abandon the previous parallelogram reduction method,adopting symmetrical transformation.In the radial mode,the overall research schemes of the wheeled pipeline inspection robot and the crawler pipeline inspection robot were proposed,and the theoretical analysis of their variable diameter ability and cornering ability was made.The analysis showed that the designed wheeled pipeline inspection robot can adapt to the inner diameter.130mm-150 mm pipe,when the pipe inner diameter is 150 mm,the minimum turning radius is 280mm;the designed crawler pipe inspection robot can adapt to the inner diameter of 135mm-160 mm pipe,when the pipe inner diameter is 150 mm,the minimum turning radius is 180 mm.Then,according to the overall research scheme,the two pipeline robots were modeled by three-dimensional software and imported into ADAMS for simulation.The reduction of the ability of the two pipeline robots,the ability to bend,the ability to overcome obstacles and the verification of the characteristics of the symmetrical reduction were analyzed.The simulation results showed that the two pipeline robots have good variable diameter ability and cornering ability and the characteristics of symmetrical variable diameter are also verified.However,it was founded that the obstacle-barrier detection robot has a significantly better obstacle-proof ability than the wheel-type pipeline detection robot.The crawler-type pipe inspection robot was produced as the final prototype.The horizontal pipeline crawling experiment,the vertical pipeline crawling experiment and the turning and crawling experiment were carried out on the crawler pipeline robotprototype,and the traction force of the robot in the horizontal pipeline and the traction force in the vertical pipeline were measured respectively.22mm/s,the traction force is about5.02N;the average speed of the pipeline robot rising in the vertical pipeline is 19mm/s,the traction force is about 0.8N;the average speed of the descending is 21mm/s,and the traction force is about 10.8N;The average speed of the turning forward is 21 mm/s,and the average speed of the turning back is 22 mm/s.Experiments show that the crawler pipe robot can crawl vertically,pass the curve smoothly and the crawling speed is stable.