Design on the Inner Wall Crawling and Inspecting Robot for Offshore Platform Leg

Abstract

Background: The legs are important base mechanism and have a key effect on the stability and security of movable offshore platform. In the application field, the work of defects detection is operated in a manual way for offshore platform leg. The main disadvantages of manual inspection can be summarized as follows: high detection cost and risk, low detection coverage and efficiency, etc. Objective: To develop a robot with an inspecting system that can crawl on the inner wall surface of the offshore platform leg, and inspect the surface defects through the inspecting system. Methods: Based on our patented technologies and the application requirements, the telescopic mechanisms, constituted by motor-screw-nut mechanism, are applied to design the body and legs mechanism of the robot. The vacuum sucker groups are applied to design the adsorption mechanism of the robot. The PLC is applied to design the measurement and movement control system. The laser ranging sensors are applied to realize the function of obstacle detection, robot location and pose analysis. The camera and its driving system are applied to design the image acquisition system. The wireless bridge is applied to design the message remote transmission system. Results: Based on the structure characteristic and the defect inspecting requirement of offshore platform leg, the wall crawling robot and its inspecting system are designed in this study. Conclusion: A series of experiments show that the robot and its inspecting system meet the demand of field applications.