Unmanned ship stabilization gyro control parameter optimization method based on genetic algorithm

Abstract

The invention provides an unmanned ship stabilization gyro control parameter optimization method based on a genetic algorithm. The unmanned ship stabilization gyro control parameter optimization method comprises the following steps: constructing an unmanned ship rolling dynamics model and an unmanned ship rolling-stabilization gyro combined dynamics model; the precession damping coefficient of the stabilization gyroscope is optimized by adopting a genetic algorithm, the relation between the precession damping coefficient and stabilization efficiency under different working conditions is established, the precession damping coefficient is continuously optimized through evolution operations such as selection, intersection and variation, and finally an optimal solution of an optimization target is obtained. The rolling three-one value of the unmanned ship is calculated; measuring a precession angle sequence; and constructing a fitness function, constructing a function relationship between the precession damping coefficient of the stabilization gyro and an optimization target, and performing optimization based on a genetic algorithm to obtain an optimal damping coefficient. According to the method, the control parameters are optimized by establishing the unmanned ship rolling-stabilization gyroscope combined kinetic model and combining random sea wave disturbance modeling, fitness function construction and a genetic algorithm optimization process, and the stabilization efficiency and adaptability are improved.

Description

Technical Field

[0001] The invention belongs to the field of roll control, and in particular relates to a method for optimizing control parameters of an unmanned boat's anti-roll gyro based on a genetic algorithm. Background Art

[0002] With the rapid development of intelligent unmanned technology, unmanned boats are increasingly being used to perform tasks in marine environments. However, in complex sea conditions, wave disturbances can cause unmanned boats to experience violent movements such as roll and pitch, which significantly affects their navigation stability and mission execution efficiency. Among them, roll, as the main form of movement, not only reduces the safety of the ship, but also causes damage to the precision equipment on board the unmanned boat.

[0003] The anti-roll gyro is a device that suppresses the ship's roll by generating a restoring torque. It has the advantages of being applicable at all speeds and taking up little space. Existing control strategies mostly use active control, which monitors the roll characteristics in real time and designs complex control algorithms to achieve stability control. However, the active control method has the problems of high algorithm complexity and high real-time requirements. In addition, when the angular velocity of the anti-roll gyro is too fast, it is easy to enter a singular state, resulting in a significant reduction in the anti-roll efficiency.

[0004] The passive control method applies damping torque, limits the precession angular velocity, releases the anti-roll torque evenly, and avoids the occurrence of singular states. However, the selection of passive control parameters has an important influence on the system performance. How to optimize the control parameters to achieve the best anti-roll effect for different ship structures and sea conditions is an important issue in current research.

[0005] As a bionic optimization algorithm, genetic algorithm searches by simulating the biological evolution process and has the characteristics of strong global optimization ability and high robustness. Summary of the invention

[0006] Aiming at the problem that the optimization of gyro control parameters in the prior art is not suitable for complex sea conditions, the present invention provides a method for optimizing the gyro control parameters of an unmanned boat based on a genetic algorithm. By establishing an unmanned boat roll-gyro joint dynamics model, combining random wave disturbance modeling, fitness function construction and genetic algorithm optimization process, the control parameters are optimized, thereby improving the roll reduction efficiency and adaptability.

[0007] The technical solution of the present invention is as follows:

[0008] The method for optimizing the control parameters of the unmanned boat anti-roll gyro based on genetic algorithm comprises the following steps:

[0009] S1: Constructing the rolling dynamics model of the unmanned boat

[0010] According to the ship rolling dynamics theory, the rolling motion equation of the unmanned boat under random wave disturbance is established:

[0011] Firstly, the roll inertia moment, damping coefficient, restoring moment and other parameters are determined, and the superposition effect of wave disturbance moment and anti-roll gyro output moment is considered to construct a complete roll dynamics model. The formula is:

[0012]

[0013] S2: Constructing the joint dynamics model of roll-stabilization gyro for unmanned boats

[0014] According to the momentum theorem, and ignoring the interference torque on the bow roll direction of the unmanned boat when the high-order trace and the anti-roll gyro precession are generated, the anti-roll gyro dynamic equation is established. In summary, the unmanned boat roll-anti-roll gyro joint dynamic model is obtained:

[0015]

[0016] S3: Genetic Algorithm Optimization

[0017] A genetic algorithm is used to optimize the damping coefficient of the anti-roll gyro. The relationship between the damping coefficient and the anti-roll efficiency under different working conditions is established. The precession damping coefficient is continuously optimized through evolutionary operations such as selection, crossover, and mutation, and finally the optimal solution is obtained.

[0018] S4: Calculate the rolling trinity value of the unmanned boat

[0019] The statistical value of the roll angle sequence within a period of time (i.e., the trinity value) is used as a parameter to measure the severity of the ship's roll. It is defined as the mean of the first 1 / 3 data of the roll angle sequence arranged in descending order. Due to the existence of nonlinear terms in the system, the fourth-order Runge-Kutta method is used to obtain the numerical solution, so as to obtain the roll angle value of the unmanned boat within the set interval and then calculate the roll angle trinity value.

[0020] S5: Measuring the precession angle sequence

[0021] When measuring the precession angle sequence, the signal spectrum S can be obtained by fast Fourier transform β (w), and then use the envelope area of ​​the high-frequency component curve to measure the jitter degree of the precession damping system.

[0022] S6: Fitness function design

[0023] In genetic algorithms, the core content is the design of fitness function.

[0024]

[0025] In the above formula, the rolling sequence of the unmanned boat when the anti-rolling is turned off and the anti-rolling is turned on are solved under the same sea conditions, which is expressed as φ N ,φP , and the anti-roll efficiency η is obtained according to formula (11) φ . Let the optimization objective function The gyro precession damping coefficient r and the anti-roll efficiency η φ A functional relationship is constructed between them, and the parameters are optimized through genetic algorithm until the optimal damping coefficient r is found. * .

[0026] The present invention has the following beneficial effects:

[0027] In response to the urgent need for high-stability observation platforms for small and medium-sized ships in marine environment detection and submarine pipeline inspection, we innovatively integrated gyro dynamics and ship seakeeping theory to construct a nonlinear roll-stabilization gyro joint dynamic model, which significantly enhanced the stability and observation accuracy of ships in complex sea conditions.

[0028] The passive control parameters of the anti-roll gyro are deeply optimized by genetic algorithms, which greatly improves the anti-roll efficiency, up to 97.44%, and effectively solves the problem of small differences in anti-roll efficiency under the initial parameters.

[0029] The output torque of the optimized anti-roll gyro system closely follows the wave disturbance torque, which further verifies the effectiveness of the optimization algorithm.

[0030] The implementation of this invention not only provides strong technical support for the stable operation of ships in severe sea conditions, but also injects new impetus into the technological progress and industrial upgrading in the fields of ocean detection and pipeline inspection, showing broad application prospects and important social value.

[0031] Other advantages, objectives and features of the present invention will be embodied in part through the following description, and in part will be understood by those skilled in the art through study and practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 A diagram showing the working principle of a gyro in an embodiment of a method for optimizing control parameters of an unmanned boat gyro based on a genetic algorithm proposed by the present invention;

[0033] Figure 2 A force analysis diagram of an unmanned boat in an embodiment of an unmanned boat anti-roll gyro control parameter optimization method based on a genetic algorithm proposed by the present invention;

[0034] Figure 3 A gyro coordinate diagram of an unmanned boat gyro control parameter optimization method based on a genetic algorithm according to an embodiment of the present invention;

[0035] Figure 4A time domain diagram and a frequency domain diagram of the gyro precession angle in an embodiment of the unmanned boat gyro control parameter optimization method based on a genetic algorithm provided by the present invention;

[0036] Figure 5 The present invention provides a flowchart of an optimization genetic algorithm in one embodiment of a method for optimizing control parameters of an unmanned boat gyro anti-rolling device based on a genetic algorithm. DETAILED DESCRIPTION

[0037] The present invention is further described in detail below in conjunction with the accompanying drawings so that those skilled in the art can implement the invention with reference to the description.

[0038] The present invention provides a method for optimizing control parameters of an unmanned boat anti-roll gyro based on a genetic algorithm, which comprises the following steps:

[0039] S1: Constructing the rolling dynamics model of the unmanned boat

[0040] According to the ship rolling dynamics theory, the rolling motion equation of the unmanned boat under random wave disturbance is established:

[0041] Firstly, the roll inertia moment, damping coefficient, restoring moment and other parameters are determined, and the superposition effect of wave disturbance moment and anti-roll gyro output moment is considered to construct a complete roll dynamics model. The formula is:

[0042]

[0043] S2: Constructing the joint dynamics model of roll-stabilization gyro for unmanned boats

[0044] According to the momentum theorem, and ignoring the interference torque on the bow roll direction of the unmanned boat when the high-order trace and the anti-roll gyro precession are generated, the anti-roll gyro dynamic equation is established. In summary, the unmanned boat roll-anti-roll gyro joint dynamic model is obtained:

[0045]

[0046] S3: Genetic Algorithm Optimization

[0047] A genetic algorithm is used to optimize the damping coefficient of the anti-roll gyro. The relationship between the damping coefficient and the anti-roll efficiency under different working conditions is established. The precession damping coefficient is continuously optimized through evolutionary operations such as selection, crossover, and mutation, and finally the optimal solution is obtained.

[0048] S4: Calculate the rolling trinity value of the unmanned boat

[0049] The statistical value of the roll angle sequence within a period of time (i.e., the trinity value) is used as a parameter to measure the severity of the ship's roll. It is defined as the mean of the first 1 / 3 data of the roll angle sequence arranged in descending order. Due to the existence of nonlinear terms in the system, the fourth-order Runge-Kutta method is used to obtain the numerical solution, so as to obtain the roll angle value of the unmanned boat within the set interval and then calculate the roll angle trinity value.

[0050] S5: Measuring the precession angle sequence

[0051] When measuring the precession angle sequence, the signal spectrum S can be obtained by fast Fourier transform β (w), and then use the envelope area of ​​the high-frequency component curve to measure the jitter degree of the precession damping system.

[0052] S6: Fitness function design

[0053] In genetic algorithms, the core content is the design of fitness function.

[0054]

[0055] In the above formula, the rolling sequence of the unmanned boat when the anti-rolling is turned off and the anti-rolling is turned on are solved under the same sea conditions, which is expressed as φ N ,φ P , and the anti-roll efficiency η is obtained according to formula (11) φ . Let the optimization objective function The gyro precession damping coefficient r and the anti-roll efficiency η φ A functional relationship is constructed between them, and the parameters are optimized through genetic algorithm until the optimal damping coefficient r is found. * .

[0056] In step 1, the specific steps of constructing the nonlinear rolling dynamic model of a ship under wave disturbance are:

[0057] S1-1: The working principle of the anti-roll gyro based on the gyro dynamics theory is as follows Figure 1 The important index to measure the anti-roll capability of the gyro is as follows:

[0058] H rotor =I rotor ·ω rotor #(1)

[0059] Where H rotor It represents the gyro angular momentum in N·m·s, I rotor Indicates the moment of inertia of the gyro rotor around its axis, in kg·m 2 ,ω rotor Indicates the rotor speed in rad / s.

[0060] S1-2: When the unmanned boat is disturbed by the waves, the moment M wave Occurs around the x-axis with an angular velocity of ω wave When the boat rolls, the anti-roll gyro connected to the hull is subjected to a disturbance torque in the same direction as the roll angular velocity. According to the gyro dynamics theory, when a high-speed rotating gyro is subjected to an external torque in a certain direction, its axis will precess in the direction perpendicular to the external torque and generate a torque in that direction. Then the precession torque and precession angular velocity of the anti-roll gyro shell generated by the external torque around the y-axis are M and M, respectively. precession ,ω precession , the gyro rotor outputs a gyroscopic torque M around the x-axis under the influence of the precession torque (external torque) gyro Since the output torque of the anti-roll gyro is in the opposite direction to the wave interference torque, the torque is applied to the hull to produce a restoring effect, thereby reducing the roll effect of the unmanned boat.

[0061] S1-3: According to S1-1 and S1-2, under the disturbance of random waves, the unmanned boat produces swaying motion in multiple directions. In order to simplify the calculation, only the rolling motion is considered. The force analysis of the unmanned boat under wave disturbance is carried out, such as Figure 2 As shown in (a), according to the ship seakeeping theory, the unmanned boat is subjected to the wave moment M W The buoyancy center Deflection occurs relative to the shape of the hull. Since the buoyancy is in the opposite direction to the gravity, a force arm G-B' is generated on the tilted side of the hull, thereby generating a restoring moment M. R .like Figure 2 As shown in (b), secondly, when the hull tilts to one side, the volume of seawater displaced on both sides changes. Due to water viscosity and wave impact, friction damping, wave damping, and vortex damping are generated on the unmanned boat, resulting in a synthetic damping moment M C In addition, due to the mass and load of the unmanned boat itself, there is an inertia moment M in the rolling direction. I The above torques constitute the combined torque in the rolling direction of the unmanned boat under wave interference, so the rolling dynamics model of the unmanned boat can be described as step 1.

[0062] In step 2, the unmanned boat roll-anti-roll gyro joint dynamics model is specifically described as:

[0063] S2-1: Explain the rolling dynamics model of the unmanned boat in step 1, where is the rolling mass inertia moment of the unmanned boat, where I xx +J xx is the coefficient of inertia moment; is the roll damping moment; M R (φ,t)=k1φ+k3φ 3 +k5φ 5 is the roll restoring moment; MW (t) = Dhα(t) is the random wave disturbance torque, where D is the displacement of the unmanned boat (t), h is the initial stability height of the unmanned boat (m), and α(t) is the random wave inclination function.

[0064] S2-2: Explain that α(t) in S2-1 is a random wave inclination function. According to water wave theory, irregular long-peak waves can be regarded as the superposition of several regular waves with different amplitudes and frequencies. This paper adopts the ITTC two-parameter wave spectrum specified by the 11th International Ship Model Tank Conference:

[0065]

[0066] Where ω is the angular frequency of the waves (rad / s), T1 is the average period of the waves (s), and h 1 / 3 is the significant wave height of the sea wave (m). When the unmanned boat is sailing on the sea, considering the influence of the speed and the angle of the wave direction encountered, the wave inclination angle function at a fixed point in the sea wave is calculated by the above wave spectrum density:

[0067]

[0068] Where γ is the encounter angle between the unmanned boat and the waves (rad); N is the number of wave harmonics; is the encounter frequency, where V is the speed of the unmanned boat (m / s); ε i ∈[0, 2π] is the initial phase angle of each harmonic (rad / s).

[0069] S2-3: S in S2-2 α (ω) is solved:

[0070] S α (ω) is the wave inclination angle spectral density function, which is calculated as follows:

[0071]

[0072] S2-4: Gyro dynamic coordinate system:

[0073] The dynamic characteristics of the anti-roll gyro need to be calculated according to the gyro dynamics theory. During use, the anti-roll gyro outer frame is generally fixed to the hull. In order to accurately calculate the output torque of the anti-roll gyro, a coordinate system is established as follows: Figure 3 As shown. With the gyro rotor center o as the origin, an inertial coordinate system o-ξηζ is established, and the gyro coordinate system o-xyz is established by rotating around the o-ξ axis by an angle φ. The gyro rotor rotates around the oz axis at a constant speed of ω0, and the gyro frame precesses around the oy axis. Assume that the anti-roll gyro is an axisymmetric rigid body structure, and the moment of inertia around the rotation axis oz is I z , the speed is ω z, the moment of inertia around the precession axis oy is J, and the speed is ω y , the moment of inertia around the ox axis is J, and the speed is ω x .

[0074] S2-5: Constructing the gyro dynamics model in a fixed coordinate system

[0075] According to the gyro coordinate system established in S2-4, the gyro dynamic equation is established according to the momentum theorem:

[0076]

[0077] Since the anti-roll gyro is fixedly connected to the hull, the rotation characteristics of the two are consistent in the ox direction. Assume that the roll angle of the unmanned boat is φ, and the angular momentum of the anti-roll gyro is h0 = I z ω0, the precession angle is β, and the higher-order traces in the above formula are ignored, which can be simplified to:

[0078]

[0079] S2-6: Transformation to the gyroscopic dynamics model in the gyroscopic coordinate system

[0080] Map the above formula to the gyro coordinate system o-ξηζ through coordinate transformation, and calculate as follows:

[0081]

[0082] From the above formula, we can know that the output torque of the anti-roll gyro in the rolling direction of the unmanned boat is Its size is proportional to the gyro's angular momentum and precession angular velocity.

[0083] In step 3, the unmanned boat genetic algorithm optimization steps are as follows:

[0084] S3-1: Initialize the population

[0085] Randomly generate multiple initial damping coefficients r i , the population size is set to M; the precession damping coefficient is limited to the range of [20,120] kg·m 2 / s.

[0086] S3-2: Fitness function calculation

[0087] Each individual r i Substitute into the roll simulation model and calculate the corresponding roll reduction efficiency η φ ;

[0088] by as the fitness value.

[0089] S3-3: Select Operation

[0090] Based on the roulette algorithm, individuals with high fitness are preferentially selected to enter the next generation.

[0091] S3-4: Crossover Operation

[0092] Generate offspring individuals through single-point crossover:

[0093] r child =αr parent1 +(1-α)r parent2

[0094] Where α is the cross-proportional coefficient.

[0095] S3-5: Mutation Operation

[0096] The damping coefficient of an individual is disturbed with a certain probability to increase the diversity of the population:

[0097] r mutated =r original +Δr

[0098] Where Δr is the random disturbance.

[0099] S3-6: Update population

[0100] Reorder according to the fitness value, retain individuals with high fitness, and repeat the iteration until convergence.

[0101] In step 4, the steps for calculating the unmanned boat roll trinity value are as follows:

[0102] S4-1: According to step 1 and step 2, according to the actual parameters of the unmanned boat (such as ship type parameters, hydrodynamic coefficients, etc.), set the corresponding simulation parameters in the model.

[0103] S4-2: Run the simulation and obtain the roll angle sequence

[0104] S4-3: Calculate the roll angle trinity value

[0105] In step 5, the steps for measuring the precession angle sequence are as follows:

[0106] S5-1: When measuring the precession angle sequence, the signal spectrum can be obtained by fast Fourier transform, and then the envelope area A of the high-frequency component curve can be used. fH To measure the degree of chattering of the precession damping system, such as Figure 4 As shown, the time domain diagram of the precession angle change and the envelope area change diagram under the conditions of r=70 and r=10 are respectively.

[0107] S5-2: According to the signal spectrum, high-frequency components (such as components in the range of 1 to 5 Hz) are extracted, and the roll angle sequence of the unmanned boat is obtained by the fourth-order Runge-Kutta method.

[0108] According to step 6, the fitness function of the unmanned ship optimization genetic algorithm is described as follows:

[0109] S6-1: According to step 4 and step 5, two optimization objectives are obtained: 1) the anti-roll efficiency is the highest; 2) the precession damping buffeting degree is the lowest, and their weight coefficients are α1 and α2 respectively, and the corresponding fitness function is constructed.

[0110] S6-2: According to steps 1-5, the algorithm fitness function is obtained:

[0111]

[0112] S6-3: According to S6-2, a functional relationship can be established between the gyro precession damping coefficient r and the optimization target J, and the genetic algorithm is used to optimize the parameters until the optimal damping coefficient r is found. * .

[0113] The present invention proposes an innovative method for optimizing the control parameters of passive ship roll reduction, which integrates the theory of ship seakeeping and gyro dynamics, and aims to improve the roll stability of unmanned boats and small ships in complex sea conditions. Aiming at the problems of low roll reduction efficiency and frequent buffeting in the existing control methods, the present invention achieves the best balance between the roll reduction efficiency and the stability of the precession system by accurately adjusting the precession damping coefficient of the anti-roll gyro. In the optimization process, we use the Matlab / Simulink platform and the fourth-order Runge-Kutta method to solve the nonlinear dynamic equations, obtain the ship roll angle time series, and design a fitness function that comprehensively considers the roll reduction efficiency and buffeting degree, and find the optimal damping coefficient through the genetic algorithm. At the same time, in order to prevent entering the singular state, we reasonably limit the precession angle and damping coefficient of the anti-roll gyro. The simulation experimental results show that the optimized anti-roll gyro system shows excellent roll reduction performance under different sea conditions, with a roll reduction efficiency of up to 97.44%, and significantly reduced buffeting, and the output torque waveform is more matched with the wave interference torque waveform. This method provides a powerful reference for the design and optimization of ship anti-roll gyro control systems and has significant engineering application potential and market prospects.

[0114] Although the embodiments of the present invention have been disclosed as above, they are not limited to the applications listed in the specification and the implementation modes. They can be fully applied to various fields suitable for the present invention. For those familiar with the art, additional modifications can be easily implemented. Therefore, without departing from the general concept defined by the claims and the scope of equivalents, the present invention is not limited to specific details.

Claims

1. The unmanned boat anti-roll gyro control parameter optimization method based on genetic algorithm is characterized by: The following steps are involved: Construct the rolling dynamics model of unmanned boat; Construct the roll-stabilization gyro joint dynamics model of the unmanned boat; The genetic algorithm is used to optimize the precession damping coefficient of the anti-roll gyro, and the relationship between the precession damping coefficient and the anti-roll efficiency under different working conditions is established. The precession damping coefficient is continuously optimized through evolutionary operations such as selection, crossover, and mutation, and finally the optimal solution of the optimization target is obtained; The unmanned boat roll trinity value is calculated according to the unmanned boat roll dynamics model and the unmanned boat roll-anti-roll gyro combined dynamics model; Measuring the precession angle sequence; A fitness function is constructed according to the unmanned boat roll trinity value and the precession angle sequence, a functional relationship between the anti-roll gyro precession damping coefficient and the optimization target is constructed, and the optimal damping coefficient is obtained by optimization based on a genetic algorithm.

2. The method for optimizing control parameters of an unmanned boat gyro based on a genetic algorithm as claimed in claim 1, characterized in that: Determine the roll inertia moment, damping coefficient, and restoring moment, consider the superposition effect of wave disturbance moment and anti-roll gyro output moment, and build a complete roll dynamics model. The formula is: In the formula is the rolling mass inertia moment of the unmanned boat, where I xx +J xx is the coefficient of inertia moment; is the roll damping moment; M R (φ, t) = k1φ + k3φ 3 +k5φ 5 is the roll restoring moment; M w (t) = Dhα(t) is the random wave disturbance torque, where D is the displacement of the unmanned boat (t), h is the initial stability height of the unmanned boat (m), and α(t) is the random wave inclination function.

3. The method for optimizing control parameters of an unmanned boat gyro based on a genetic algorithm as claimed in claim 2, characterized in that: Building a rolling dynamics model includes the following steps: The working principle of the anti-roll gyro based on the gyro dynamics theory and the important index to measure the anti-roll gyro's anti-roll ability are expressed as follows: H rotor =I rotor ·ω rotor #(1) Where H rotor It represents the gyro angular momentum in N·m·s, I rotor Indicates the moment of inertia of the gyro rotor around its axis, in kg·m 2 ,ω rotor Indicates the rotor speed in rad / s; When the unmanned boat is disturbed by the waves, the moment M wave Occurs around the x-axis with an angular velocity of ω wave When the boat rolls, the anti-roll gyro connected to the hull is subjected to a disturbance torque in the same direction as the roll angular velocity; according to the gyro dynamics theory, when a high-speed rotating gyro is subjected to an external torque in a certain direction, its axis will precess in the direction perpendicular to the external torque and generate a torque in that direction. Then the precession torque and precession angular velocity of the anti-roll gyro shell generated by the external torque around the y-axis are M and M respectively. precession ,ω precession , the gyro rotor outputs a gyroscopic torque M around the x-axis under the influence of the precession torque gyro , since the output torque of the anti-roll gyro is in the opposite direction to the wave interference torque, the torque is applied to the hull to produce a restoring effect, thereby reducing the rolling effect of the unmanned boat; Under the disturbance of random waves, the unmanned boat produces swaying motion in multiple directions. In order to simplify the calculation, only the rolling motion is considered. The force analysis of the unmanned boat under wave disturbance is carried out. According to the ship seakeeping theory, the unmanned boat is subjected to wave moment M. W The buoyancy center deflects relative to the shape of the hull. Since the buoyancy is in the opposite direction to the gravity, a force arm G-B' is generated on the tilted side of the hull, thereby generating a restoring moment M. R ; Secondly, when the hull tilts to one side, the volume of seawater displaced on both sides changes. Due to water viscosity and wave impact, friction damping, wave damping, and vortex damping are generated on the unmanned boat, resulting in a synthetic damping moment M C In addition, due to the mass and load of the unmanned boat itself, it has an inertia moment M in the rolling direction. I .

4. The method for optimizing control parameters of an unmanned boat gyro based on a genetic algorithm as claimed in claim 1, characterized in that: According to the momentum theorem, and ignoring the interference torque on the bow roll direction of the unmanned boat caused by the high-order trace and the precession of the anti-roll gyro, the anti-roll gyro dynamic equation and the unmanned boat roll-anti-roll gyro joint dynamic model are established: Where the precession angle is β, and the output torque of the anti-roll gyro in the rolling direction of the unmanned boat is Its size is proportional to the gyro's angular momentum and precession angular velocity.

5. The method for optimizing control parameters of unmanned boat gyro based on genetic algorithm as claimed in claim 3, characterized in that: The construction of the unmanned boat roll-stabilization gyro joint dynamics model includes the following steps: According to water wave theory, irregular long-peaked waves can be regarded as the superposition of several regular waves with different amplitudes and frequencies; the ITTC two-parameter wave spectrum specified by the 11th International Ship Model Tank Conference is adopted: Where ω is the angular frequency of the waves (rad / s), T1 is the average period of the waves (s), and h 1 / 3 is the significant wave height of the sea wave (m). When the unmanned boat is sailing on the sea, considering the influence of the speed and the angle of the wave direction encountered, the wave inclination angle function at a fixed point in the sea wave is calculated by the above wave spectrum density: Where γ is the encounter angle between the unmanned boat and the waves (rad); N is the number of wave harmonics; is the encounter frequency, where V is the speed of the unmanned boat (m / s); ε i ∈[0,2π] is the initial phase angle of each harmonic (rad / s); For S α (ω) is solved: S α (ω) is the wave inclination angle spectral density function, which is calculated as follows: Gyro dynamic coordinate system: The dynamic characteristics of the anti-roll gyro need to be calculated according to the gyro dynamics theory. During use, the outer frame of the anti-roll gyro is generally fixed to the hull. In order to accurately calculate the output torque of the anti-roll gyro, a coordinate system is established. The inertial coordinate system o-ξηζ is established with the center o of the gyro rotor as the origin. The gyro coordinate system o-xyz is established by rotating the gyro rotor around the o-ξ axis at an angle of φ. The gyro rotor rotates around the oz axis at a constant speed of ω0, and the gyro frame precesses around the oy axis. The anti-roll gyro is assumed to be an axisymmetric rigid body structure, and the moment of inertia around the rotation axis oz is I z , the speed is ω z , the moment of inertia around the precession axis oy is J, and the speed is ω y , the moment of inertia around the ox axis is J, and the speed is ω x ; Constructing the gyro dynamics model in a fixed coordinate system According to the gyro coordinate system and the momentum theorem, the gyro dynamic equation is established: Since the anti-roll gyro is fixedly connected to the hull, the rotation characteristics of the two are consistent in the ox direction; Assume that the roll angle of the unmanned boat is φ, and the angular momentum of the anti-roll gyro is h0 = I z ω0, the precession angle is β, and the higher-order traces in the above formula are ignored, which can be simplified to: Transform the anti-roll gyro dynamic model into the gyro coordinate system Map the above formula to the gyro coordinate system o-ξηζ through coordinate transformation, and calculate as follows:

6. The method for optimizing control parameters of an unmanned boat gyro based on a genetic algorithm as claimed in claim 5, characterized in that: The optimization steps of the unmanned boat genetic algorithm are as follows: Initialize the population: randomly generate multiple initial damping coefficients r i , the population size is set to M; the precession damping coefficient is limited to the range of [20, 120] kg·m2 / s; Fitness function calculation: Each individual r i Substitute into the roll simulation model and calculate the corresponding roll reduction efficiency η φ ;by As the fitness value; Selection operation: Based on the roulette algorithm, individuals with high fitness are given priority to enter the next generation; Crossover operation: Generate offspring individuals through single-point crossover: r ch ild ＝αr parent1 +(1-α)r parent2 Where α is the cross-proportional coefficient; Mutation operation: perturb the damping coefficient of an individual with a certain probability to increase the diversity of the population: r mutated =r original +Δr Where Δr is the random disturbance; Update the population: reorder according to the fitness value, retain individuals with high fitness, and repeat the iteration until convergence.

7. The method for optimizing control parameters of unmanned boat gyro based on genetic algorithm as claimed in claim 6, characterized in that: The statistical value of the roll angle sequence within a period of time, namely the trinity value, is used as a parameter to measure the severity of the ship's roll. It is defined as the mean of the first 1 / 3 data of the roll angle sequence arranged in descending order. Due to the existence of nonlinear terms in the system, the fourth-order Runge-Kutta method is used to obtain the numerical solution, so as to obtain the roll angle value of the unmanned boat within the set interval and then calculate the trinity value of the roll angle.

8. The method for optimizing control parameters of an unmanned boat gyro based on a genetic algorithm as claimed in claim 6, characterized in that: The steps to measure the precession angle sequence are as follows: When measuring the precession angle sequence, the signal spectrum can be obtained by fast Fourier transform, and then the envelope area A of the high-frequency component curve can be used to calculate the signal spectrum. fH To measure the degree of buffeting of the precession damping system; According to the signal spectrum, the high-frequency components are extracted, and the roll angle sequence of the unmanned boat is obtained by the fourth-order Runge-Kutta method.

9. The method for optimizing control parameters of an unmanned boat gyro based on a genetic algorithm as claimed in claim 6, characterized in that: The fitness function of the unmanned ship optimization genetic algorithm is described as follows: Two optimization objectives are obtained: 1) the highest anti-roll efficiency; 2) the minimum degree of precession damping buffeting, whose weight coefficients are α1 and α2 respectively, and the corresponding fitness function is constructed; Algorithm fitness function: In the above formula, the rolling sequence of the unmanned boat when the anti-rolling is turned off and the anti-rolling is turned on are solved under the same sea conditions, which is expressed as φ N ,φ P , and the anti-roll efficiency η is obtained according to formula (11) φ ; Let the optimization objective function A functional relationship can be established between the gyro precession damping coefficient r and the optimization target J, and the parameters can be optimized through genetic algorithm until the optimal damping coefficient r is found. * .

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