Design Of Marine Seismic Streamer Control Strategy And Experimental Research Based On Intelligent Optimal Algorithms

Marine streamer system is key equipment of four-dimensional seismicexploration technology. The quality of the exploration is closely relatedwith the control of streamer. The design of seismic streamer control systemis a research hotspot over the world. Based on the dynamic model of thestreamer, simulation and experimental research has been performed tostudy the dynamic characteristics of underwater towed cable. Then thecontrol strategies of seismic streamer have been designed basing onintelligent optimal algorithms, which are boundary control, ant colonyalgorithm and fuzzy control algorithm.The establishment of Mathematical model is based on several basicassumptions of the towed cable system, and kinetic equation is determinedfrom the analysis of cable element. The calculation method of outer forcesacting on the cable is determined. Basing on the assumption of small angleof attack, a liner mathematical model and boundary conditions have beenfounded. Then it gives the kinetic equation of the controller node.To study the dynamic characteristics of a zero buoyancy marinestreamer with guide rope and towed tail under different frequencysinusoidal excitation, a math model for a zero buoyancy streamer isestablished and an experiment is designed. In the experiment, Front-endtension and displacement on streamer with different towed speed anddifferent excitation frequency are measured. An elastic mechanism isdesigned to enlarge the tension signal. The elastic mechanism has goodlinearity, and the reliability of the experiment has been proved by theconclusion analysis. The comparison of front-end tension from numerical calculation and experiment confirmed the correctness of the model.Preliminary analysis of dynamic characteristics under sinusoidal excitationis investigated at last.Basing on the linear model and energy function of marine streamer, asuitable objective function is founded, and a boundary control strategy hasbeen designed with consideration of the disturbance of the uncontrolledpart of steamer. Numerical simulation has been done to check the controllaw which at last has confirmed the applicability of the boundary controlstrategy.Ant colony algorithm comes from the simulation of ants which areforaging their path from nest to food. The functions of state transitionprobability and pheromone adjusting probability have been founded and anant colony optimal algorithm has been designed to optimize the controlparameters of the streamer controller. The control result has shownobvious superiority compared to Z-N method PID controller.A Fuzzy controller is designed to fulfill the depth control target of thesteamer. Fuzzy sets and membership functions have been constructed andthe chart of fuzzy inference rules has been formed. Through the FuzzyLogic toolbox of MATLAB, the fuzzy controller is designed. By thesimulation in Simulink, the applicability of fuzzy control is verified.Through the comparison of the control results with Z-N method and Antalgorithm, the superiority of Fuzzy-PI controller is proved.