Routing Plan Of Remotely Operated Vehicle For Jacket Inspection

Recent years, remotely operated vehicle (ROV) begin to do more and more inspecting works of all kinds of offshore structures instead of divers, because it is less expensive and safer. However, different from the works that can be done on land, ROV's underwater inspection is still a kind of high-cost project. This paper takes a jacket of Huizhou oil field for example, studied the constrained routing plan of ROV for jacket's state inspection. The purpose is to improve inspecting efficiency and reduce inspecting expense by routing plan, which could guide the ROV's movement to decrease redundant or duplicate routes and save working hours.First, the inspection tasks was decomposed and classified according to the structure and the vulnerable parts of the jacket and the kinetics characteristics of the ROV's movement.The test-programs were designed, the test-points were selected and finally a correct mathematical model was established based on the study of relative theory and all kinds of algorithm. Then, the traversal route of the ROV for jacket inspection was designed and realized respectively according to different methods which suitable for edge-travel and point-travel relevant to GVI inspection and CP test. In this processes, graph theory, ant colony algorithms and simulation annealing optimization algorithms were used. Through numerous matlab simulation, parameters optimization, result's comparation and analyse, the routing plan of ROV for jacket inspection was fully studied. The planning methods and the simulating results have significant theoretical value and guiding meanings.In the end of this paper, an approximate algorithm for CP measurement which belongs to point-travel was designed in an edge-travel method. The similarity between these two traversal methods was analyzed. The constraint of the ROV's movement during the process of CP inspection was realized by adding auxiliary nodes to the inspecting graph. A traversal method by finding the best spanning tree was proposed, by which we can construct a semi-Euler graph to find a better traversal trace. A traversal trace was finally found. Both the results and the method are very important in engineering inspection for its effective routes and the practical values.