A test-based wave glider motion prediction method and a method for optimizing design parameters

Abstract

The application discloses a wave glider motion prediction method and an optimized design parameter method based on experiments, and comprises the following steps: assigning values to the initial speed and initial position of a floating body and an underwater traction machine, obtaining umbilical cable tension and umbilical cable resistance in the initial state through an umbilical cable dynamics formula; bringing the umbilical cable tension into a floating body dynamics model to obtain the speed of the floating body; bringing the umbilical cable tension and the umbilical cable resistance into an underwater traction machine dynamics equation to obtain the speed of the underwater traction machine; respectively integrating the floating body speed and the underwater traction machine speed to obtain displacement parameters, obtaining coordinate parameters through the displacement parameters, substituting the coordinate parameters into the umbilical cable dynamics formula, and solving the umbilical cable tension and the resistance; bringing the umbilical cable tension into the floating body dynamics model, bringing the umbilical cable tension and the resistance into the underwater traction machine dynamics model, repeating the above steps, and realizing the motion prediction of the wave glider. The application can improve the precision of a simulation model.

Description

Technical Field

[0001] This invention relates to the field of wave glider motion research technology, and in particular to an experimental wave glider motion prediction method and a method for optimizing design parameters. Background Technology

[0002] A wave glider is an unmanned autonomous surface vehicle propelled by wave energy, consisting of a float, umbilical cable, and underwater tractor. When gliders navigate in complex marine environments, their motion is influenced by waves and ocean currents. Simulation modeling can predict the impact of these factors on the glider's performance, thereby optimizing its design and operational strategies, and ensuring its stability and navigation efficiency in various sea conditions.

[0003] While some motion prediction methods exist for wave gliders, these methods still have limitations, primarily in their inability to accurately simulate the strong nonlinear characteristics of the underwater tractor and umbilical cable under fluid interaction. Currently developed wave glider motion simulation models rely on simplified assumptions or lack comprehensive experimental verification, thus limiting their accuracy and applicability in real-world scenarios. To address these limitations, this invention proposes an experimental-based wave glider motion prediction method. Summary of the Invention

[0004] This invention provides, in one aspect, an experiment-based method for predicting the motion of wave gliders, thereby improving the accuracy of simulation models. In another aspect, this invention provides a method for optimizing the design parameters of wave gliders.

[0005] The first aspect of the present invention provides an experimental method for predicting the motion of a wave glider, comprising the following steps:

[0006] The velocity and position coordinates of the floating body and the underwater tractor in a static state are assigned values, and the umbilical cable tension and umbilical cable resistance in a static state are obtained through the umbilical cable dynamics formula.

[0007] The tension of the umbilical cable in a static state is incorporated into the dynamic equation of the floating body to obtain the velocity of the floating body at the first moment.

[0008] The actual swing angle of the airfoil in a static state is obtained by using the moment balance equation of the airfoil.

[0009] The nonlinear relationship between lift and drag and the wing plate swing angle of the underwater towing machine was obtained by conducting lift and drag characteristic tests on the underwater towing machine. A relationship table of wing plate swing angle and lift and drag of the underwater towing machine was made. By using the relationship table of wing plate swing angle and lift and drag of the underwater towing machine, the lift and drag of the underwater towing machine corresponding to the actual swing angle of the wing plate in the stationary state was obtained.

[0010] The umbilical cable tension and umbilical cable resistance in the static state, and the lift-drag of the underwater tractor in the static state are brought into the underwater tractor dynamics equation to obtain the speed of the underwater tractor at the first time:

[0011] The obtained speed of the floating body at the first time is integrated to obtain the displacement parameter of the floating body at the first time, the obtained speed of the underwater tractor at the first time is integrated to obtain the displacement parameter of the underwater tractor at the first time, and the position coordinates of the floating body and the underwater tractor in the static state are combined to obtain the coordinate parameter of the floating body and the coordinate parameter of the underwater tractor at the first time, and the coordinate parameter of the floating body and the coordinate parameter of the underwater tractor at the first time, the speed of the floating body at the first time are brought into the umbilical cable dynamics formula, and the umbilical cable tension and resistance at the first time are solved;

[0012] The above step is repeated until the speed of the floating body, the speed of the underwater tractor, the coordinate parameter of the floating body, the coordinate parameter of the underwater tractor, and the umbilical cable tension and resistance at all times are obtained;

[0013] The speed of the floating body, the speed of the underwater tractor, the coordinate parameter of the floating body, the coordinate parameter of the underwater tractor, the umbilical cable tension and resistance, the actual swing angle of the wing plate, and the actual swing angle of the wing plate corresponding to the lift-drag of the underwater tractor at all times are used to predict the motion of the wave glider.

[0014] The wave glider motion prediction method based on experiments, preferably, the umbilical cable dynamics formula is:

[0015] (1)

[0016] (2)

[0017] wherein, is the umbilical cable tension; is the umbilical cable resistance; is the umbilical cable stiffness; is the distance between the floating body and the underwater tractor; is the length of the umbilical cable; is the gravity of the underwater tractor; is the buoyancy of the underwater tractor; is the speed of the floating body at the first time.

[0018] The wave glider motion prediction method based on experiments, preferably, the floating body dynamics equation is:

[0019] (3)

[0020] (4)

[0021] wherein, is the inertia matrix of the float; is the added mass force of the float; is the centripetal and Coriolis force matrix of the float; is the centripetal and Coriolis force matrix of the added mass force of the float; is the damping matrix of the float; is the force and moment due to gravity and buoyancy of the float; is the force of the umbilical acting on the float; is the wave force of the float.

[0022] The test-based wave glider motion prediction method, preferably, the underwater tow vehicle dynamics equation is:

[0023] (5)

[0024] (6)

[0025] wherein, is the inertia matrix of the underwater tow vehicle; is the added mass force of the underwater tow vehicle; is the centripetal and Coriolis force matrix of the underwater tow vehicle; is the centripetal and Coriolis force matrix of the added mass force of the underwater tow vehicle; is the damping matrix of the underwater tow vehicle; is the force and moment due to gravity and buoyancy of the underwater tow vehicle; is the force of the umbilical acting on the underwater tow vehicle; is the velocity of the underwater tow vehicle; is the lift and drag force of the underwater tow vehicle.

[0026] The test-based wave glider motion prediction method, preferably, the wing panel moment balance equation is:

[0027] (7)

[0028] (8)

[0029] (9)

[0030] (10)

[0031] (11)

[0032] (12)

[0033] (13)

[0034] (14)

[0035] where, is the resultant moment on the wing; is the moment of gravity and buoyancy of the wing; is the moment of lift of the wing; is the moment of drag of the wing; is the moment of spring force of the wing; is the moment of stop force of the wing; is the moment of damping force of the wing; is the moment of inertia of the wing; is the arm of gravity; is the arm of hydrodynamic force; is the arm of spring force; is the arm of stop force; is the mass of the wing; is the acceleration of gravity; is the buoyancy of the wing; is the lift of the wing; is the drag of the wing; is the spring force of the wing; is the tilt angle of the wing; is the spring deformation of the wing during oscillation; is the spring stiffness of the wing; is the stop force of the wing; is the damping force of the wing during oscillation.

[0036] The second aspect of the present application provides a method for optimizing the design parameters of a wave glider, based on the above-mentioned test-based wave glider motion prediction method, the optimization method comprising the following steps:

[0037] Firstly, a target sea state is selected, and corresponding wave parameters are set in the body dynamics equation;

[0038] According to the existing design parameters of the wave glider, corresponding parameter items are set in the body dynamics equation, the underwater thruster dynamics equation, the umbilical cable dynamics formula and the moment balance equation of the wing;

[0039] For the spring at the wing of the underwater thruster, different spring parameters are selected;

[0040] SIMULINK is used to carry out simulation and modeling through the body dynamics equation, the underwater thruster dynamics equation, the umbilical cable dynamics formula and the moment balance equation of the wing, so as to obtain the motion data of the wave glider under the corresponding sea state and corresponding spring parameters.

[0041] Sequentially change the target sea state and spring parameters, carry out simulation, and obtain the motion data of the wave glider under different working conditions;

[0042] Compare the simulation results, optimize, and obtain the spring design parameters that make the wave glider have the best propulsion performance.

[0043] Preferably, the wave parameters are wave height and period.

[0044] Preferably, the parameter items include the geometric parameters of the floating body, the geometric parameters of the umbilical cable, the geometric parameters of the underwater traction machine, the initial speed and initial coordinates of the floating body, the initial speed and initial coordinates of the underwater traction machine, the rigidity of the umbilical cable, and the parameters of the spring.

[0045] Preferably, the parameters of the spring include the hanging point position, the spring pre-tension, and the spring rigidity.

[0046] The beneficial effects are:

[0047] The test data directly obtained through the test method can directly reflect the real hydrodynamic characteristics of the underwater traction machine, can avoid the errors caused by the simplification assumptions, and ensures the accuracy of the model parameters.

[0048] Since the resistance performance of the umbilical cable directly affects the navigation efficiency of the wave glider, using accurate umbilical cable resistance parameters in the modeling process can greatly improve the accuracy of the wave glider motion simulation model.

[0049] A whole simulation model of the wave glider is established through the Matlab-Simulink software. The wave glider motion modeling method based on the test data is proposed, which ensures the accuracy of the wave glider motion model.

[0050] The reliability of the modeling method can be directly verified through the verification test, and the credibility of the method is enhanced. The modeling method proposed in the application is no longer limited to the qualitative research level of the wave glider speed, but the research dimension is improved to the quantitative level.

[0051] The wing plate elastic module is added in the modeling method proposed in the application, so that the influence of the elastic parameters of the wing plate on the motion performance of the wave glider can be directly studied by using the model.

[0052] The application establishes a complete test-based wave glider motion prediction method, a simulation model established based on the hydrodynamic parameters of the umbilical cable and the underwater towing machine obtained through test can improve the precision of the simulation model, and the wave glider motion test can verify the simulation model, thereby proving the reliability of the simulation model. BRIEF DESCRIPTION OF DRAWINGS

[0053] Figure 1 The flowchart of the application is shown. DETAILED DESCRIPTION

[0054] To make the purpose, technical scheme and advantages of the application clearer, the technical scheme of the application will be described clearly and completely below with reference to the drawings. Obviously, the described embodiments are part of the embodiments of the application, rather than all the embodiments. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the application.

[0055] The application provides a test-based wave glider motion prediction method based on test, which is characterized by comprising the following steps:

[0056] The initial velocity of the floating body and the initial velocity of the underwater towing machine are respectively 0, and the initial position coordinates of the floating body and the underwater towing machine are valued according to the actual situation, the umbilical cable tension and the umbilical cable resistance in the initial state are obtained through the umbilical cable dynamics formula, the floating body velocity is integrated to obtain the displacement parameters of the floating body, and the velocity of the underwater towing machine The integral is performed to obtain the displacement parameters of the underwater traction machine, initial position coordinates of the floating body and the underwater traction machine at the initial moment are given, and then the coordinate parameters of the floating body and the underwater traction machine are obtained, the coordinate parameters of the floating body and the coordinate parameters of the underwater traction machine are substituted into the umbilical cable dynamics formula, and the umbilical cable tension and the resistance are solved; the umbilical cable tension is brought into the floating body dynamics model to obtain the speed of the floating body at the next moment, the umbilical cable tension and the umbilical cable resistance are brought into the underwater traction machine dynamics equation to obtain the speed of the underwater traction machine at the next moment, and the integral is performed on the obtained speed to obtain the coordinate parameters of the floating body and the coordinate parameters of the underwater traction machine respectively, the coordinate parameters of the floating body and the coordinate parameters of the underwater traction machine are substituted into the umbilical cable dynamics formula, and the umbilical cable tension and the resistance are solved again; the above steps are repeated to obtain the speed of the floating body and the speed of the underwater traction machine at all moments, the wing plate swing angle, the posture and tension of the umbilical cable, and the lift and drag of the underwater traction machine in the motion change process of the wave glider under different wave parameters are calculated by using the floating body dynamics model, the umbilical cable dynamics formula and the underwater traction machine dynamics equation, so that the motion of the wave glider is predicted. The present application establishes a complete wave glider motion prediction method based on test, and the simulation model established based on the hydrodynamic parameters of the umbilical cable and the underwater traction machine obtained by test can improve the accuracy of the simulation model. At the same time, the wave glider motion test can verify the simulation model, thereby proving the reliability of the simulation model.

[0057] The entire technical process is described in detail below taking a wave glider motion prediction method based on test as an example.

[0058] Embodiment 1

[0059] As shown in Figure 1 , a wave glider motion prediction method based on test, specifically comprising the following steps:

[0060] S1: The speed and position coordinates of the floating body and the underwater traction machine in the static state are valued, and the umbilical cable tension and the umbilical cable resistance in the static state are obtained through the umbilical cable dynamics formula;

[0061] (1)

[0062] (2)

[0063] Wherein,

[0064] is the umbilical cable tension;

[0065] is the umbilical cable resistance;

[0066] The specific acquisition method is: through the patent "a water dynamic performance testing device and method for a flexible umbilical cable of a wave glider" with application number 202410800626.4, the umbilical cable resistance characteristic test is carried out, the corresponding umbilical cable resistance under different umbilical cable tension and umbilical cable speed is obtained, the resistance characteristic database is established, and the corresponding and query the resistance characteristic database, and the corresponding .

[0067] is the stiffness of the umbilical cable, which is set according to the actual physical parameters.

[0068] is the distance between the floating body and the underwater traction machine, which is calculated and obtained from the displacement parameters of the floating body and the underwater traction machine. is the length of the umbilical cable, is the gravity of the underwater traction machine, is the buoyancy of the underwater traction machine, which is set according to the physical parameters.

[0069] is the speed of the umbilical cable, which is the same as the speed of the floating body ;

[0070] is the speed of the floating body.

[0071] S2: the umbilical cable tension in the static state is brought into the floating body dynamics equation to obtain the speed of the floating body at the first time,

[0072] (3)

[0073] (4)

[0074] wherein, is the force vector of the umbilical cable acting on the floating body, including the forces in x, y and z directions. Since the wave glider is symmetrical about the X and Z planes, the force of the umbilical cable in the y direction is 0, and since the force of the umbilical cable in the x direction is the resistance, and the underwater traction machine is the power component of the wave glider, the resistance of the umbilical cable is defined to the motion equation of the underwater traction machine, therefore, the composition of the force of the umbilical cable acting on the floating body is as shown in formula (4).

[0075] is the inertia matrix of the floating body, is the added mass force of the floating body, is the centripetal force and Coriolis force matrix of the floating body, is the centripetal force and Coriolis force matrix of the added mass force of the floating body, is the damping matrix of the floating body,

[0076] is the force and moment caused by the gravity and buoyancy of the float, which is obtained by empirical formula,

[0077] is the force of the umbilical cable acting on the float,

[0078] is the wave force of the float, which is obtained based on the hydrodynamic parameters of the float calculated by the AQWA software, i.e. the wave height, period and the basic hydrodynamic parameters of the float are input in simulink to obtain the wave force of the float.

[0079] is the velocity of the float.

[0080] S3: the actual swing angle of the wing plate of the underwater traction machine in the static state is obtained by using the moment balance equation of the wing plate. The moment balance equation of the wing plate is:

[0081] (7)

[0082] (8)

[0083] (9)

[0084] (10)

[0085] (11)

[0086] (12)

[0087] (13)

[0088] (14)

[0089] wherein, is the resultant moment of the wing plate, is the gravity moment and buoyancy moment of the wing plate, is the lift moment of the wing plate, is the drag moment of the wing plate, is the spring force moment of the wing plate, is the limiting force moment of the wing plate, is the damping force moment of the wing plate, is the moment of inertia of the wing plate, which is obtained according to the solving formula or empirical formula in the prior art;

[0090] is the gravity arm, which is obtained according to the actual parameters of the wing plate;

[0091] is the water dynamic force arm, for the actual parameter acquisition of the wing plate;

[0092] is the spring force arm, for the actual parameter acquisition of the wing plate;

[0093] is the limit force arm, for the actual parameter acquisition of the wing plate;

[0094] is the wing plate mass, is the gravity acceleration, is the wing plate buoyancy, the above data are actual measurement values;

[0095] is the wing plate lift, is the wing plate drag, determined by the lift-drag characteristics test of the underwater traction machine and the actual wing plate swing angle of the underwater traction machine. The device and method used in the lift-drag characteristics test of the underwater traction machine adopt the device and method disclosed in the patent "Wave Glider Underwater Traction Machine Lift-Drag Measurement Device and Method" with the application number 202311160247.5.

[0096] is the spring force of the wing plate;

[0097] is the tilt angle of the wing plate hanging point, obtained according to the actual swing position of the wing plate;

[0098] is the spring deformation amount in the swing process of the wing plate, obtained according to the actual swing position of the wing plate;

[0099] is the spring stiffness of the wing plate, selected according to the actual spring design;

[0100] is the limit force of the wing plate, selected according to the actual design parameters;

[0101] is the damping force in the swing process of the wing plate, selected according to the actual design parameters.

[0102] S4: Obtain the nonlinear relationship between the lift-drag force and the wing plate angle of the underwater traction machine through the underwater traction machine lift-drag force characteristic test, make a wing plate angle-lift-drag force relationship table of the underwater traction machine, and obtain the corresponding lift-drag force of the underwater traction machine at the actual swing angle of the wing plate in the static state through the wing plate angle-lift-drag force relationship table of the underwater traction machine. The device and method of the underwater traction machine lift-drag force characteristic test adopt the device and method in the patent "Wave glider underwater traction machine lift-drag force measuring device and method" with the application number 202311160247.5.

[0103] S5: The umbilical cable tension and umbilical cable resistance in the static state, the lift-drag force of the underwater traction machine in the static state are brought into the underwater traction machine dynamics equation to obtain the speed of the underwater traction machine at the first time:

[0104] (5)

[0105] (6)

[0106] wherein, is the force vector of the umbilical cable acting on the underwater traction machine, including the forces in x, y, and z directions. Since the wave glider is symmetrical about the XZ plane, the force of the umbilical cable in the y direction is 0. Since the force in the x direction on the umbilical cable is the resistance, and the underwater traction machine is the power component of the wave glider, the resistance of the umbilical cable is defined into the motion equation of the underwater traction machine. Since the umbilical cable is located between the upper floating body and the lower underwater traction machine, the force of the umbilical cable acting on the underwater traction machine in the z direction is equal in size and opposite in direction, therefore, the composition of the force of the umbilical cable acting on the underwater traction machine is as shown in formula (6).

[0107] is the inertia matrix of the underwater traction machine, which is obtained through an empirical formula;

[0108] is the added mass force of the underwater traction machine, which is obtained through an empirical formula;

[0109] is the centripetal force and Coriolis force matrix of the underwater traction machine, which is obtained through an empirical formula;

[0110] is the centripetal force and Coriolis force matrix of the added mass force of the underwater traction machine, which is obtained through an empirical formula;

[0111] is the damping matrix of the underwater traction machine, which is directly obtained through the underwater traction machine lift-drag force characteristic test, that is, the underwater traction machine lift-drag force coefficient directly contains this item, and no additional solution is needed;

[0112] is the force and moment caused by the gravity and buoyancy of the underwater thruster, which is obtained by an empirical formula;

[0113] is the force of the umbilical cable acting on the underwater thruster;

[0114] is the speed of the underwater thruster;

[0115] is the lift and drag of the underwater thruster, which is obtained by the method of step S4.

[0116] S6: Integrate the speed of the floating body at the first time obtained in step S2 to obtain the displacement parameter of the floating body, integrate the speed of the underwater thruster at the first time obtained in step S5 to obtain the displacement parameter of the underwater thruster, and combine the position coordinates of the floating body and the underwater thruster in the static state to obtain the coordinate parameters of the floating body and the underwater thruster at the first time, and then bring the coordinate parameters of the floating body at the first time and the coordinate parameters of the underwater thruster at the first time into the umbilical cable dynamics formula to solve the umbilical cable tension and the umbilical cable resistance at the first time.

[0117] S7: Bring the umbilical cable tension at the first time in step S6 into the floating body dynamics equation again to obtain the speed of the floating body at the second time, and bring the umbilical cable tension and the umbilical cable resistance at the first time in step S6 into the underwater thruster dynamics equation again to obtain the speed of the underwater thruster at the second time, and integrate the speed of the floating body and the speed of the underwater thruster at the second time to obtain the coordinate parameters of the floating body and the underwater thruster at the second time respectively, and then bring the coordinate parameters of the floating body and the coordinate parameters of the underwater thruster into the umbilical cable dynamics formula to solve the umbilical cable tension and the umbilical cable resistance at the second time again. Repeat step S7 until the speed of the floating body and the speed of the underwater thruster, the coordinate parameters of the floating body and the underwater thruster, the umbilical cable tension and the umbilical cable resistance at the third time to the Nth time are obtained.

[0118] S8: Use the speed of the floating body, the speed of the underwater thruster, the coordinate parameters of the floating body and the underwater thruster, the umbilical cable tension and resistance, the actual swing angle of the wing plate, and the corresponding underwater thruster lift and drag at the actual swing angle of the wing plate at all times to realize the prediction of the motion of the wave glider.

[0119] That is, the swing angle of the wing plate in the motion change process of the wave glider under different wave parameters is obtained by the actual swing angle of the wing plate at all times, and the posture of the umbilical cable is obtained by the coordinate parameters of the floating body and the underwater thruster.

[0120] Embodiment 2

[0121] A method for optimizing the design parameters of a wave glider, comprising the formulas (1) to (14) in the wave glider motion prediction method based on experiments described in Embodiment 1, specifically comprising the following steps:

[0122] S1: First, select the target sea state, and set the corresponding wave parameters in the body dynamics equation; wherein the wave parameters are wave height and period.

[0123] S2: According to the existing design parameters of the wave glider, set the corresponding parameter items in the body dynamics equation, underwater thruster dynamics equation, umbilical cable dynamics formula and wing plate torque balance equation; wherein the parameter items include the geometric parameters of the body, the geometric parameters of the umbilical cable, the geometric parameters of the underwater thruster, the initial speed and initial coordinates of the body, the initial speed and initial coordinates of the underwater thruster, the stiffness of the umbilical cable and the parameters of the spring.

[0124] S3: For the spring at the wing plate of the underwater thruster, select different spring parameters; wherein the spring parameters include the hanging point position, the spring pre-tension and the spring stiffness.

[0125] S4: Use SIMULINK to carry out simulation and modeling through the body dynamics equation, underwater thruster dynamics equation, umbilical cable dynamics formula and wing plate torque balance equation, and obtain the motion data of the wave glider under the corresponding sea state and corresponding spring parameters;

[0126] S5: Change the target sea state and spring parameters in turn, carry out simulation and modeling, and obtain the motion data of the wave glider under different working conditions;

[0127] S6: Compare the simulation results, optimize, and obtain the spring design parameters that make the wave glider propulsion performance best.

[0128] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, and not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement to part of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A test-based wave glider motion prediction method, characterized by, The method comprises the following steps: Assigning the speed and position coordinates of the floating body and the underwater tow machine in the static state, and obtaining the umbilical cable tension and umbilical cable resistance in the static state through the umbilical cable dynamics formula; Bringing the umbilical cable tension in the static state into the floating body dynamics equation to obtain the speed of the floating body at the first time; Obtaining the actual swing angle of the wing plate in the static state by using the torque balance equation of the wing plate; Obtaining the nonlinear relationship between the lift-drag force and the wing plate swing angle of the underwater tow machine through the lift-drag force characteristic test of the underwater tow machine, preparing a wing plate swing angle-lift-drag force table of the underwater tow machine, and obtaining the corresponding lift-drag force of the underwater tow machine at the actual swing angle of the wing plate in the static state through the wing plate swing angle-lift-drag force table of the underwater tow machine; Bringing the umbilical cable tension and umbilical cable resistance in the static state and the lift-drag force of the underwater tow machine in the static state into the underwater tow machine dynamics equation to obtain the speed of the underwater tow machine at the first time; Integrating the obtained speed of the floating body at the first time to obtain the displacement parameter of the floating body at the first time, integrating the obtained speed of the underwater tow machine at the first time to obtain the displacement parameter of the underwater tow machine at the first time, and combining the position coordinates of the floating body and the underwater tow machine in the static state to obtain the coordinate parameters of the floating body and the underwater tow machine at the first time, and bringing the coordinate parameters of the floating body and the underwater tow machine at the first time and the speed of the floating body at the first time into the umbilical cable dynamics formula to solve the umbilical cable tension and resistance at the first time; Repeating the above step until the speed of the floating body, the speed of the underwater tow machine, the coordinate parameters of the floating body and the underwater tow machine, and the umbilical cable tension and resistance at all times are obtained; Using the speed of the floating body, the speed of the underwater tow machine, the coordinate parameters of the floating body and the underwater tow machine, the umbilical cable tension and resistance, the actual swing angle of the wing plate, and the corresponding lift-drag force of the underwater tow machine at the actual swing angle of the wing plate to predict the motion of the wave glider.

2. The trial-based wave glider motion prediction method according to claim 1, characterized in that, The umbilical cable dynamics formula is: （1） （2） wherein, is umbilical tension; is umbilical resistance; is umbilical stiffness; is the distance between the floating body and the underwater tractor; is the length of the umbilical; is the weight of the underwater tractor; is the buoyancy of the underwater tractor; is the speed of the floating body at the 1st time.

3. The trial-based wave glider motion prediction method according to claim 2, characterized in that, The floating body dynamics equation is: （3） （4） wherein is the mass matrix of the float; is the added mass force of the float; is the centripetal and Coriolis force matrix of the float; is the centripetal and Coriolis force matrix of the added mass force of the float; is the damping matrix of the float; is the force and moment due to gravity and buoyancy of the float; is the force of the umbilical acting on the float; is the wave force of the float.

4. The trial-based wave glider motion forecasting method according to claim 3, characterized in that, The underwater tow machine dynamics equation is: （5） （6） wherein, is the mass matrix of the underwater tug; is the added mass force of the underwater tug; is the centripetal and Coriolis force matrix of the underwater tug; is the centripetal and Coriolis force matrix of the added mass force of the underwater tug; is the damping matrix of the underwater tug; is the force and moment due to gravity and buoyancy of the underwater tug; is the force of the umbilical on the underwater tug; is the velocity of the underwater tug; is the lift and drag force of the underwater tug.

5. The trial-based wave glider motion forecasting method of claim 4, wherein, The torque balance equation of the wing plate is: （7） （8） （9） （10） （11） （12） （13） （14） wherein, is the resultant moment on the wing panel; is the gravitational moment and the buoyant moment of the wing panel; is the lift moment of the wing panel; is the drag moment of the wing panel; is the spring force moment of the wing panel; is the limit force moment of the wing panel; is the damping force moment of the wing panel; is the moment of inertia of the wing panel; is the gravitational force arm; is the hydrodynamic force arm; is the spring force arm; is the limit force arm; is the mass of the wing panel; is the gravitational acceleration; is the buoyancy of the wing panel; is the lift of the wing panel; is the drag of the wing panel; is the spring force of the wing panel; is the tilt angle of the wing panel hanging point; is the spring deformation amount in the wing panel swing process; is the spring stiffness of the wing panel; is the limit force of the wing panel; is the damping force in the wing panel swing process.

6. A method of optimizing design parameters of a wave glider, characterized by, The test-based wave glider motion prediction method based on claim 5 comprises the following steps: First, select the target sea state and set the corresponding wave parameters in the floating body dynamics equation; According to the existing design parameters of the wave glider, set the corresponding parameter items in the floating body dynamics equation, the underwater tow machine dynamics equation, the umbilical cable dynamics formula, and the torque balance equation of the wing plate; Select different spring parameters for the spring at the wing plate of the underwater tow machine; Use SIMULINK to carry out simulation and emulation through the floating body dynamics equation, the underwater tow machine dynamics equation, the umbilical cable dynamics formula, and the torque balance equation of the wing plate to obtain the motion data of the wave glider under the corresponding sea state and the corresponding spring parameter; Change the target sea state and the spring parameter in turn, carry out simulation and emulation, and obtain the motion data of the wave glider under different working conditions; The simulation results are compared and optimized to obtain the spring design parameters that make the wave glider propulsion performance optimal.

7. The method of optimizing the design parameters of a wave glider according to claim 6, characterized in that, The wave parameters are wave height and period.

8. The method of optimizing the design parameters of a wave glider according to claim 6, characterized in that, The parameter items include the geometric parameters of the floating body, the geometric parameters of the umbilical, the geometric parameters of the underwater tractor, the initial speed and initial coordinates of the floating body, the initial speed and initial coordinates of the underwater tractor, the stiffness of the umbilical, and the parameters of the spring.

9. The method of optimizing the design parameters of a wave glider as claimed in claim 6, wherein, The parameters of the spring include the hanging point position, the spring pre-tension, and the spring stiffness.

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