Research On Dynamics And Deployment Scheme Of Fiber Optic Micro-cable Applied In Deep-sea ARV

Autonomous & Remotely-operated Vehicle(ARV),as a new type of underwater vehicle that emerged in recent years,has improved human's ability to explore and study the deep sea.ARV uses fiber optic micro-cable as the medium for real-time communication with the mother ship,and get rid of the limitation of traditional umbilical cable.ARV can do not only wide-range cruising observations and also detailed fixed-point survey.Therefore,studying the dynamics response of fiber optic micro-cable and the suitable cable deployment scheme during the ARV movement is of great significance to the reliability and safety of the ARV system.First,by using the finite segment method,a simplified model of fiber optic micro-cable is established.The cable is discretized as a series of extensible straight rods that are free connected.This model can simulate the 3-D motion of large-range cables by using a smaller number of segments.The nonlinear governing equations are established by deriving the constitutive equations and mechanics equilibrium of cable segments and transformed into an optimization equation.Aiming at the problem that the stability of the traditional Newton method is sensitive to the initial value when solving the nonlinear equations.The particle swarm algorithm is used to optimize the initial value of the Newton method in a large range,and then get the optimal solution by the Newton method.The hybrid optimization idea is applied to the static and dynamic calculation of fiber optic micro-cable.Then,through the comparison of multiple sets of calculation examples,this paper analyzes the dynamics response of the fiber optic micro-cable during the ARV movement and analyzes the factors that affect the safety of the cable.Many meaning conclusions are obtained,which provide a reference for a safe cable deployment scheme.Finally,this paper calculates a lot of dynamics data and establish a neural network to train data.The payout rate of cable can be determined according to various parameters that affect the safety of the cable.By controlling the tension in a suitable range,a safe and feasible cable deployment scheme can be carried out.