Deep-Sea Two-Pipe Rope Measurement Method Based On Uncertainty Analysis Research And Experiments

Obtaining the relative position of the subsea pipeline to meet the accuracy requirements is a key step in solving the pipeline reattachment problem.This topic comes from the special project "Deep sea pipeline back connection laying technology".The aim of this research is to improve the accuracy of the rope measurement method and to objectively evaluate the measurement results.Based on the uncertainty theory,an uncertainty evaluation method is proposed for different positioning methods to achieve quantitative analysis and evaluation of the measurement errors.This paper analyses the current situation of the development of underwater measurement technology at home and abroad,and compares and concludes that the rope measurement method has feasibility and practical significance when applied to practical engineering.From the perspective of the accuracy requirements of the subject,the importance and significance of uncertainty assessment for submarine pipeline position measurement is presented.By studying the current status of uncertainty development in the field of underwater measurement at home and abroad,a direction and theoretical foundation is laid for subsequent theoretical research.This paper establishes and analyses the underwater mechanics model of the measurement rope,and by comparing and analysing the parabolic and drape theories,determines a more suitable calculation method for engineering applications,and proposes a calculation method for the measurement rope based on this theory.The design of the reel winch and the study of rope deformation under tension and environmental effects are investigated.In order to solve the problem that it is difficult to adopt a uniform method to evaluate the measurement results of the pipeline position,a modeling process is proposed for the uncertainty evaluation of the measurement device applicable to different positioning methods,and a measurement model based on the measurement device of different positioning methods is established to solve the relative position information between two pipes based on robot theory and transition matrix algorithm.Finally,the propagation coefficients in the uncertainty theory are analysed according to the resulting measurement models,laying the foundation for uncertainty analysis.This paper systematically describes the uncertainty analysis process in the following way:by analysing the sources of uncertainty and classifying and evaluating the measurement components,solving for the degrees of freedom of each component,and then completing the solution of the synthetic standard uncertainty based on the uncertainty propagation rate.To provide intervals for the measurement results,the solution of the extended uncertainty is proposed.In this paper,terrestrial experiments based on two experimental devices with different positioning methods are carried out to verify the plausibility of the proposed uncertainty analysis method.Through initial commissioning of the device and pre-modulation of the inclination sensor,magnetically coupled encoder and rope length detection mechanism,it is verified that all functional units work properly and meet the accuracy requirements,and the applicability and necessity of the uncertainty analysis method proposed in this paper is verified through comprehensive positional measurement experiments.