High-precision amphibious vehicle water motion simulation platform construction method and system

Abstract

The invention discloses a high-precision amphibious vehicle water motion simulation platform construction method and system, and relates to the technical field of vehicle simulation, and the method comprises the steps: obtaining the propulsion system configuration and parameters of an amphibious vehicle, and calculating a thrust database through the computational fluid mechanics principle; based on rigid body and fluid dynamics theories, a water dynamics model and an environment disturbance model are established. A high-precision water dynamics simulation program code is compiled and optimized, and an amphibious vehicle water motion simulation platform is developed in combination with an unreal engine. Based on the method, a high-precision amphibious vehicle water dynamics simulation platform can be established.

Description

Technical Field

[0001] The present application relates to the field of automobile simulation technology, and in particular to a method and system for constructing a high-precision amphibious vehicle water sports simulation platform. Background Art

[0002] Amphibious vehicles are cross-domain platforms with excellent environmental adaptability, strong off-road capabilities, and good performance in complex mission scenarios. Since the advent of amphibious vehicles in the 20th century, they have been active in various military missions and have become a military reserve force that countries have been competing to develop. With the development of various technologies applied to amphibious vehicles, amphibious vehicles are now widely used in the civilian field, participating in surveying and mapping, meteorological monitoring, transportation and other industries. The research and development of amphibious vehicles faces the challenges of long cycles and high costs. Although real vehicle tests can accurately evaluate dynamic performance, cost and efficiency issues lead to the use of model tests to predict performance, which also prolongs the development cycle. Therefore, a high-precision water dynamics simulation platform is essential for predicting performance and rapid design and parameter optimization.

[0003] At present, the existing research on amphibious vehicle simulation platforms mostly uses relatively simple models for model-based motion simulation, and does not consider the disturbance of the environmental model on the water motion of amphibious vehicles. This type of method has the following limitations: 1) Model-based methods take into account both computing speed and real-time interaction, but due to the differences in model accuracy, parameters and other descriptive differences, it will lead to model mismatch problems; 2) Due to ignoring the influence of environmental disturbances, this type of simulation method is difficult to simulate the different performances of amphibious vehicles in different sea conditions and different scenarios; 3) Low-order models will miss the influence of certain dimensions on the motion of amphibious vehicles when describing the water motion of amphibious vehicles, and the overall performance is unreasonable for the dynamics of the whole vehicle. Summary of the invention

[0004] The purpose of this application is to provide a method and system for constructing a high-precision amphibious vehicle water sports simulation platform, which can establish a high-precision amphibious vehicle water dynamics simulation platform

[0005] To achieve the above objectives, this application provides the following solutions:

[0006] In a first aspect, the present application provides a method for constructing a high-precision amphibious vehicle water sports simulation platform, comprising:

[0007] The vehicle information of the amphibious vehicle is obtained; the vehicle information includes the system configuration and vehicle parameters of the propulsion system of the amphibious vehicle.

[0008] According to the system configuration of the propulsion system of the amphibious vehicle and based on the principle of computational fluid dynamics, the propulsion system of the amphibious vehicle is calculated to obtain a thrust database of the amphibious vehicle.

[0009] According to the vehicle parameters of the amphibious vehicle, based on rigid body dynamics and fluid dynamics theory, a water dynamics model of the amphibious vehicle is established.

[0010] An environmental disturbance model is established based on the theories of aerodynamics, wave mechanics and ocean current dynamics.

[0011] Based on the water dynamics model and environmental disturbance model of the amphibious vehicle, an integrated development environment tool is used to compile a high-precision water dynamics simulation program code for the amphibious vehicle.

[0012] Based on computational fluid dynamics, with the goal of improving the simulation accuracy of amphibious vehicles, an optimized simulation code is obtained for the high-precision amphibious vehicle water dynamics simulation program code.

[0013] Combine the optimized simulation code with Unreal Engine to create a water sports simulation platform for amphibious vehicles in Unreal Engine.

[0014] In a second aspect, the present application provides a high-precision amphibious vehicle water sports simulation platform construction system, comprising:

[0015] The information acquisition module is used to acquire vehicle information of the amphibious vehicle; the vehicle information includes the system configuration and vehicle parameters of the propulsion system of the amphibious vehicle.

[0016] The calculation module is used to calculate the propulsion system of the amphibious vehicle according to the system configuration of the propulsion system of the amphibious vehicle based on the principle of computational fluid dynamics, so as to obtain the thrust database of the amphibious vehicle.

[0017] The model building module is used to establish a water dynamics model of the amphibious vehicle according to the vehicle parameters of the amphibious vehicle based on rigid body dynamics and fluid dynamics theory.

[0018] The information acquisition module is used to establish an environmental disturbance model based on the theories of aerodynamics, wave mechanics and ocean current dynamics.

[0019] The code writing module is used to write high-precision amphibious vehicle water dynamics simulation program code based on the water dynamics model and environmental disturbance model of the amphibious vehicle using an integrated development environment tool.

[0020] The code optimization module is used to obtain optimized simulation code for the high-precision amphibious vehicle water dynamics simulation program code based on computational fluid dynamics with the goal of improving the simulation accuracy of the amphibious vehicle.

[0021] A platform building module for combining optimized simulation code with Unreal Engine to create a water sports simulation platform for amphibious vehicles in Unreal Engine.

[0022] According to the specific embodiments provided in this application, this application discloses the following technical effects:

[0023] The present application provides a method and system for constructing a high-precision amphibious vehicle water sports simulation platform, the method comprising: obtaining detailed vehicle information of the amphibious vehicle, focusing on the system configuration and vehicle parameters of its propulsion system. Subsequently, according to the system configuration of the propulsion system, the principle of computational fluid dynamics will be used to accurately calculate the propulsion system to build and fill the thrust database of the amphibious vehicle; then, based on the detailed data of the vehicle parameters, the rigid body dynamics and fluid dynamics theory will be integrated to build an accurate water dynamics model to simulate the dynamic behavior of the amphibious vehicle on the water surface; based on the theories of aerodynamics, wave mechanics and ocean current dynamics, an environmental disturbance model will be built to capture and simulate the impact of various external factors on the operation of the vehicle; using the integrated development environment tool, a high-precision performance amphibious vehicle water dynamics simulation program code will be written; the program will be based on the aforementioned water dynamics model and environmental disturbance model to achieve accurate simulation of the vehicle's water motion state; in order to further improve the accuracy of the simulation, the initial simulation program code will be optimized under the guidance of computational fluid dynamics; finally, the optimized simulation code will be combined with the Unreal Engine to build a water motion simulation environment for amphibious vehicles on the Unreal Engine platform. The method based on this application can achieve high-precision simulation of the motion state of amphibious vehicles in complex environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0025] Figure 1 A schematic flow chart of a method for constructing a high-precision amphibious vehicle water sports simulation platform provided in one embodiment of the present application.

[0026] Figure 2 A schematic diagram of the framework of a method for constructing a high-precision amphibious vehicle water sports simulation platform provided in one embodiment of the present application.

[0027] Figure 3 A framework diagram of a solution calculation step provided for an embodiment of the present application.

[0028] Figure 4A schematic diagram of the functional modules of a system for constructing a high-precision amphibious vehicle water sports simulation platform provided in one embodiment of the present application. DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0030] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, the present application is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0031] Embodiment 1

[0032] like Figure 1 As shown, this embodiment provides a method for constructing a high-precision amphibious vehicle water sports simulation platform, comprising:

[0033] Step 101: Acquire vehicle information of an amphibious vehicle; the vehicle information includes system configuration and vehicle parameters of a propulsion system of the amphibious vehicle.

[0034] Step 102: According to the system configuration of the propulsion system of the amphibious vehicle and based on the principle of computational fluid dynamics, the propulsion system of the amphibious vehicle is calculated to obtain a thrust database of the amphibious vehicle.

[0035] Step 103: According to the vehicle parameters of the amphibious vehicle, based on rigid body dynamics and fluid dynamics theory, a water dynamics model of the amphibious vehicle is established.

[0036] Step 104: Establish an environmental disturbance model based on the theories of aerodynamics, wave mechanics and ocean current dynamics.

[0037] Step 105: Based on the water dynamics model and environmental disturbance model of the amphibious vehicle, an integrated development environment tool is used to compile a high-precision amphibious vehicle water dynamics simulation program code.

[0038] Step 106: Based on computational fluid dynamics, with the goal of improving the simulation accuracy of the amphibious vehicle, the high-precision amphibious vehicle water dynamics simulation program code is optimized to obtain the simulation code.

[0039] Step 107: Combine the optimized simulation code with the Unreal Engine to create an amphibious vehicle water sports simulation platform in the Unreal Engine.

[0040] When executing step 101, the specific steps may be as follows:

[0041] The system configuration of the propulsion system of the amphibious vehicle obtained is a dual-thruster system configuration.

[0042] The acquired vehicle parameters may be size parameters of the vehicle, including but not limited to the length, width, height, and weight of the vehicle.

[0043] When executing step 102, the specific steps may be as follows:

[0044] Firstly, the system configuration of the propulsion system is determined, taking a common dual-thruster amphibious vehicle as an example; in order to accurately describe the performance of the propulsion system under different control quantities, a database supporting the amphibious vehicle simulation platform is established.

[0045] Due to the complex shape of the pump system and the changes in the flow field caused by movement, the hydrodynamic calculation and analysis is quite complicated. The motion equation of viscous incompressible fluid is used to solve the external flow field of the propulsion pump:

[0046]

[0047] Where ρ is the fluid density; v is the velocity vector of the fluid at time t; is the Laplace operator; p is the pressure; F is the external force vector; the constant μ is the dynamic viscosity coefficient (dynamic viscosity μ).

[0048] Considering that the flow in the power system pipeline is a circular pipe flow, and the water jet problem in the rotating flow domain such as the pump blade guide vane, the multi-coordinate sliding grid model (MRF) is used in combination with the RNG k-ε model for calculation. The RNG k-ε model improves the Standard k-ε model based on the renormalization group theory and considers the influence of the average strain rate in the rotating coordinate system.

[0049] The eddy viscosity of this model can be expressed as a function of the turbulent dissipation rate ε and the turbulent kinetic energy:

[0050]

[0051] The transport equation of turbulent kinetic energy k is expressed as follows:

[0052]

[0053] The transport equation of the dissipation rate ε is expressed as follows:

[0054]

[0055] in, c1=1.42,c μ=0.085, c2=1.68, σ k =0.7179,σ ε =1.3.

[0056] The pump propulsion calculation domain is divided into four parts: the outlet section, the impeller area, the guide vane area, and the water inlet channel section. The dimensionless wall distance is used to divide the near-wall area of ​​each part. The near-wall grid structure is arranged after calculating the value of , and the first layer of grid height on the nozzle wall is about 0.35 mm. The sliding grid model (MRF) based on the multi-moving reference system is used to process the rotating area. The inlet flow channel section and the impeller area, the impeller area and the guide vane area are connected through the frozen rotor interface, and the guide vane area and the vector nozzle section are connected through the static-static interface.

[0057] The rotating flow domain is set as a rotating grid, and the conventional flow area is set as a stationary grid. The inlet flow channel forms an unstructured grid by appropriately adding nodes, local grid encryption is performed in the inlet and outlet areas, and boundary layer grids are used in the flow channel and the near-wall area of ​​the pump shaft.

[0058] Finally, the reliability of the simulation is analyzed based on the safety factor to ensure the reliability of the database. According to the commonly used control quantities of the dual-thruster amphibious vehicle, namely the speed of the dual-side propulsion pumps and the opening of the dual-side water gates, the propulsion force and torque generated by the amphibious vehicle propulsion system in the three degrees of freedom of longitudinal, transverse and bow swing under different working conditions are calculated to form a propulsion system database to facilitate subsequent development. According to the different types of amphibious vehicle propulsion that need to be calculated, it can be extended to different forms of propulsion systems such as propellers, pod propulsion, and azimuth propulsion.

[0059] When executing step 103, the specific steps may be as follows:

[0060] In the derivation of the kinematic equations of an amphibious vehicle, the following two assumptions are usually made: the amphibious vehicle is a rigid body; the NED coordinate system {n} is regarded as an inertial system (ignoring the rotation speed of the earth)

[0061] According to hypothesis 2:

[0062]

[0063] in and are the velocity vectors of the center of mass of the rigid body relative to the inertial system {i} and the NED coordinate system {n}, respectively. and is the angular velocity vector of the rigid body relative to the inertial frame {i} and the NED coordinate frame {n}.

[0064] According to Euler's first law, we can deduce:

[0065]

[0066] in, is the external force acting on the center of gravity, represents the time differential in the inertial system {i}, the dot is defined as the time derivative of the variable, and the S function is the vector cross product. and are the velocity vectors of the center of mass of the rigid body relative to the inertial system {i} and the NED coordinate system {n}, respectively. and is the angular velocity vector of the rigid body relative to the inertial frame {i} and the NED coordinate frame {n}.

[0067] The above vector expression (6) describes the translation about CG in the body coordinate system {b}, as shown in equation (7):

[0068]

[0069] The derivation of rotational dynamics is similar to the above derivation process:

[0070]

[0071] In the formula, is the external moment acting on the center of gravity, I g is the rotational inertia matrix about the center of gravity. The vector expression (8) in {b} describes the rotational motion about the CG:

[0072]

[0073] According to the Newton-Euler equations for translational and rotational motion of the center of gravity CG, the equation of motion for CG can be obtained:

[0074]

[0075] Among them, I 3×3 is the 3×3 identity matrix, 0 3×3 is a 3×3 zero matrix. For the dynamics of the amphibious vehicle, this embodiment generally uses an arbitrary point CO as the origin of the description motion system. The arbitrary point CO can utilize the geometric properties of the amphibious vehicle to simplify the number of certain parameters and the computational complexity.

[0076] The above-derived equation of motion about the center of gravity CG needs to be converted into the equation of motion about CO.

[0077] CO and CG have the following vector relationship:

[0078]

[0079] in is the position vector from CO to CG. The time differential of the above equation in {n} can be written as equation (12):

[0080]

[0081] Based on assumption 1, the rigid body satisfies:

[0082]

[0083] The velocities of CG and CO are related as follows:

[0084]

[0085] According to assumption 1, the angular velocity of any two points on the rigid body is the same: The following relationship can be obtained:

[0086]

[0087] in, is the center of gravity vector in {b}, Defined as a transformation matrix.

[0088] According to the parallel axis theorem and rigid body dynamics, there is the following relationship:

[0089]

[0090]

[0091] Convert equation (10) into the equation of motion about point CO:

[0092]

[0093] Expanding and simplifying the first line of equation (18) yields the translation about CO:

[0094]

[0095] According to the parallel axis theorem (Huygens-Steiner Theorem), for any origin o where CO is located b , its inertia matrix I b satisfy:

[0096]

[0097] According to the Jacobi discriminant: a×(b×c)+b×(c×a)+c×(a×b)=0, we can get:

[0098]

[0099] but It can be expressed as:

[0100]

[0101] Expanding the second line of equation (18) yields the rotational motion about CO:

[0102]

[0103] According to the vector representation of SNAME notation, the translation equation (19) and rotation equation (23) about CO are expanded to obtain the nonlinear 6-DOF rigid body motion equations:

[0104]

[0105] Rigid body dynamics are expressed in vector form:

[0106]

[0107] Considering the rigid body dynamics of ocean vehicles

[0108]

[0109] Among them, M RB is the rigid body mass matrix, C RB is the rigid body Coriolis force and centripetal force matrix, τ RB It is a generalized external force, including fluid dynamics, fluid statics, wind and wave forces, and control forces. v is the velocity and angular velocity of the six degrees of freedom.

[0110] In fluid dynamics, it is usually assumed that the fluid dynamic forces and fluid dynamic moments acting on a rigid body can be linearly superimposed. The fluid dynamic forces consist of the following components: the additional mass M caused by the inertia of the fluid surrounding the vehicle A ; Due to the rotation of the body coordinate system {b} relative to the north-east ground {n}, the additional mass produces the corresponding Coriolis and centripetal matrices C A (v r ). Radiation-induced potential damping D due to energy carried by surface waves P Viscous damping τ due to surface friction, wave drift damping, vortex shedding, and lift / drag visc The resulting nonlinear fluid dynamic mass-spring-damper force can be expressed as:

[0111]

[0112] τ hs =-g(η)-g0 (28).

[0113] Then, the nonlinear steering equation can be obtained:

[0114]

[0115] Generally speaking, all degrees of freedom have coupling terms. However, in practical applications, some coupling terms are small enough, so some coupling terms with small effects are ignored when deriving the model. In addition, the following assumptions are applied in the process of deriving the model: the amphibious vehicle is a rigid body, the ocean currents in the basin environment are steady and irrotational; the amphibious vehicle is regarded as a box-shaped vehicle, that is, the waterline area is unchanged; the amphibious vehicle is bilaterally symmetrical, that is, it is regarded as XZ symmetric; the longitudinal and oscillatory motion of the amphibious vehicle is decoupled.

[0116] Among them, the rigid body inertia matrix M RB Expands to:

[0117]

[0118] Expand the Coriolis force and centripetal force matrix C in parametric form RB (v):

[0119]

[0120] According to equation (31), the inertia matrix M of the decoupled additional mass is given as A :

[0121]

[0122] For a rigid body moving in an ideal fluid, the hydrodynamic Coriolis and centripetal force matrices C are A (v) can be M A Parameterization, we get formula (33):

[0123]

[0124] Among them, linear damping consists of potential damping and viscous damping, as shown in formula (34):

[0125]

[0126] D n (ν r ) is the nonlinear damping matrix caused by quadratic damping and higher-order terms, as follows:

[0127]

[0128] Hydrostatic force is caused by the tilt of the amphibious vehicle due to disturbance, which breaks the balance between gravity and buoyancy. It can be expressed as follows:

[0129]

[0130] Among them A wpis the waterline area of ​​the amphibious vehicle, ▽ is the displacement volume of the amphibious vehicle when floating, GM T To ensure horizontal stability, GM L For vertical center height, L fo is the x-axis distance from the floating center CF to the {b} origin CO.

[0131] At this point, the additional mass matrix M A , the additional mass Coriolis force and centripetal force matrix C A (v r ), the fluid dynamic damping matrix D(v r ) give expressions in the form of fluid dynamic derivatives.

[0132] Based on the inertia matrix calculated from the amphibious vehicle itself and the amphibious vehicle thrust database, the water dynamics model of the amphibious vehicle can be obtained.

[0133] When executing step 104, the specific steps may be as follows:

[0134] In the dynamic system of an amphibious vehicle, environmental forces usually include the forces and torques exerted on the vehicle by wind, waves and ocean currents. In the control system, it is generally assumed that wind and wave disturbances can be superimposed. In general, environmental forces are highly nonlinear and have additive and multiplicative properties on the dynamic equations of motion.

[0135] Wind is defined as air moving relative to the Earth's surface. Let Vw and γw denote wind speed and angle of attack, respectively.

[0136] The relationship between the angle of attack γw and the wind speed Vw, wind direction βw, and heading ψ is:

[0137] γ w =ψ-β w -π (37).

[0138] Define relative wind speed Vrw and relative wind direction γrw:

[0139]

[0140] The relative wind speed component is

[0141]

[0142] Define the wind force formula:

[0143]

[0144] In the formula, ρ a is the air density, H Fw and H Lw are the heights of the centroids of the front projection area AFw and the side projection area ALw above the water surface, and Loa is the total length of the amphibious vehicle.X (γ rw ), C Y (γ rw ), C Z (γ rw ), C K (γ rw ), C M (γ rw ), C N (γ rw ) is the wind coefficient related to the angle of attack.

[0145] The wave force can be considered as an average slowly varying part and an oscillating part. In order to study the influence of wave force on the control system, the first-order wave force and the second-order wave force of the oscillating part are usually considered separately.

[0146] τ wave =τ wave1 +τ wave2 (41).

[0147] The wave force RAO is converted into the form of a transfer function, and the wave spectrum is approximated by a linear filter:

[0148] τ wave1 =H s (s)n(s) (42).

[0149] Among them, H s (s) = Kdiag{h1(s), h2(s), h3(s), h4(s), h5(s), h6(s)} is the approximate diagonal matrix of the 6DOF wave spectrum S(ω), K = diag{k1, k2, k3, k4, k5, k6} is the adjustable gain, and n(s) is the zero-mean Gaussian white noise. This approximate model has good performance and robustness in closed-loop feedback control systems. Taking a single degree of freedom as an example, the wave spectrum can be approximated by a second-order system:

[0150]

[0151] Where λ is the damping coefficient selected according to sea conditions and wave spectrum, ω e is the encounter frequency. Usually the value of k is defined as follows:

[0152] k=2λω e σ (44).

[0153] Where σ is a constant describing the wave strength. The energy spectral density function P of the approximate system is defined as h (ω).

[0154]

[0155] When ω=ωe When P h (ω) and S(ω) should achieve equal maximum values:

[0156]

[0157] In the formula, the value of λ is chosen so that It is established or obtained by fitting the wave spectrum curve.

[0158] The second-order wave drift force is approximated by a random walk process: where d is zero-mean Gaussian white noise.

[0159] Ocean currents are horizontal and vertical circulation systems of seawater caused by gravity, wind friction and changes in water density in different parts of the ocean. The generalized velocity of an irrotational steady ocean current is defined as: where u c ,v c ,w c is expressed in the body coordinate system {b}, that is, Then the ocean current velocity is expressed in {n} as:

[0160]

[0161] Because the ocean current is steady, the derivative of the above equation is 0, and we can get:

[0162]

[0163] Easy to get:

[0164]

[0165] The calculation of relative velocity is defined as follows:

[0166]

[0167] According to the following formula (51), formula (52) can be obtained:

[0168]

[0169]

[0170] Then, substituting into the vehicle dynamics model, the dynamics model under the influence of ocean currents can be obtained, as shown in formula (53):

[0171]

[0172] When executing step 105, the specific steps may be as follows:

[0173] According to the aquatic dynamics model formula of the amphibious vehicle derived in step 103 and step 104, the corresponding C++ code is written in this embodiment. The solution calculation process is detailed in Figure 3 . In the code, firstly, the generalized coordinates are clarified and the initial parameter values ​​are input. Subsequently, according to the state parameters and control parameters of the amphibious vehicle at the current time point, the propulsion force generated by the propulsion system, the force caused by the rigid body inertia matrix and the fluid damping force are accurately calculated. Next, by simulating the given environmental parameters, including wind, waves, flow and other factors, the influence of these factors on the motion state of the amphibious vehicle is evaluated. Thereafter, the calculated forces and torques are substituted into the amphibious vehicle dynamics model to solve the generalized acceleration. Subsequently, the fourth-order Runge-Kutta method is used for integration operation to predict and calculate the state parameters at the next time point, while considering the control parameters provided by the interactive system. The calculation results are fed back to the calculation process as the initial conditions for the next iteration, and the calculations at subsequent time points are repeated in this way. Through the above process, this embodiment successfully develops a set of real-time, interactive, high-precision amphibious vehicle water dynamics simulation program codes, which realizes the accurate simulation and analysis of the water motion state of the amphibious vehicle.

[0174] When executing step 106, the specific steps may be as follows:

[0175] Based on the method of computational fluid dynamics, the model is optimized and iterated. First, the model of the amphibious vehicle is established. Then, based on the complexity of different structural areas, structured grids with different densities are divided respectively. The appropriate turbulence model and free surface model are selected, and the external flow field of the amphibious vehicle is solved based on the finite volume method. Numerical calculations are performed on specific working conditions of the amphibious vehicle, such as straight flight, turning, and Z-shaped maneuvers. The results are compared and analyzed with the results of the dynamic simulation calculation in step 3. The dynamic model parameters in the simulation are corrected so that the simulation results are as close as possible to the results of the numerical calculation of fluid mechanics. The above steps are repeated, and the model parameters are gradually iterated. Finally, the residual of the selected comparison evaluation index is controlled within 1%, and the optimization of the simulation dynamic model parameters of the amphibious vehicle is completed.

[0176] When executing step 107, the specific steps may be as follows:

[0177] The final optimized code was combined with the Unreal Engine to build a real-time, interactive, high-precision amphibious vehicle water dynamics simulation platform.

[0178] A basic model of an amphibious vehicle is built in the Unreal Engine, including a body shell, a running mechanism, a propulsion device, a wave plate, a tail flap and other components, and a complete amphibious vehicle model is built based on the assembly of the above components. The optimized dynamic simulation code obtained in step 105 is combined with the tracked vehicle model in the Unreal Engine, and a real-time simulation software for an amphibious vehicle is built based on the UE4 engine. The simulation software solves the real-time motion state of the amphibious vehicle through an integrated environmental system, vehicle model, dynamic model and control system, and outputs the motion state and scene interaction of the amphibious vehicle through UE4 engine rendering, and visualizes the simulation calculation results so that users can intuitively view the calculation results. The overall framework of an amphibious vehicle water simulation platform with real-time interaction and animation demonstration written independently is formed.

[0179] Considering user friendliness during the integration process, the corresponding user interface is developed based on the Qt platform, including basic functions such as amphibious vehicle motion control instructions, component parameter modification, and motion process display. During the development process, corresponding external data interfaces are reserved so that the developed simulation platform can support the operation of decision-making perception planning control algorithms, and finally build a fully autonomous, real-time, interactive, and high-precision water dynamics simulation platform for amphibious vehicles.

[0180] Embodiment 2

[0181] like Figure 4 As shown, this embodiment provides a high-precision amphibious vehicle water sports simulation platform construction system, including:

[0182] The information acquisition module 401 is used to acquire vehicle information of the amphibious vehicle; the vehicle information includes the system configuration and vehicle parameters of the propulsion system of the amphibious vehicle.

[0183] The calculation module 402 is used to calculate the propulsion system of the amphibious vehicle according to the system configuration of the propulsion system of the amphibious vehicle based on the principle of computational fluid dynamics, so as to obtain the thrust database of the amphibious vehicle.

[0184] The model building module 403 is used to build a water dynamics model of the amphibious vehicle according to the vehicle parameters of the amphibious vehicle based on rigid body dynamics and fluid dynamics theory.

[0185] The information acquisition module 404 is used to establish an environmental disturbance model based on the theories of aerodynamics, wave mechanics and ocean current dynamics.

[0186] The code writing module 405 is used to write a high-precision amphibious vehicle water dynamics simulation program code based on the water dynamics model and environmental disturbance model of the amphibious vehicle using an integrated development environment tool.

[0187] The code optimization module 406 is used to obtain optimized simulation code for the high-precision amphibious vehicle water dynamics simulation program code based on computational fluid dynamics with the goal of improving the accuracy of amphibious vehicle simulation.

[0188] The platform construction module 407 is used to combine the optimized simulation code with the Unreal Engine to create an amphibious vehicle water sports simulation platform in the Unreal Engine.

[0189] Among them, the platform building modules include:

[0190] The initial model building submodule is used to build an initial model of an amphibious vehicle simulation platform based on the Unreal Engine; the initial model includes a body shell, tires and suspension.

[0191] The platform building submodule is used to combine the optimized simulation code with the initial model of the amphibious vehicle simulation platform in the Unreal Engine, and use the Unreal Engine to visualize the calculation results of the optimized simulation code to obtain the amphibious vehicle dynamics simulation platform.

[0192] In summary, this application has the following technical effects:

[0193] The simulation platform established in this application improves the accuracy and credibility of simulation by combining computational fluid dynamics and dynamic model optimization, while supporting complex three-dimensional motion analysis and multi-parameter adjustment, and has an environmental factor editing interface and a friendly visual interactive interface, which enhances the applicability and scalability of the model.

[0194] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0195] This article uses specific examples to illustrate the principles and implementation methods of this application. The description of the above embodiments is only used to help understand the method and core ideas of this application. At the same time, for those skilled in the art, according to the ideas of this application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting this application.

Claims

1. A method for constructing a high-precision amphibious vehicle water sports simulation platform, characterized in that: include: Acquiring vehicle information of the amphibious vehicle; the vehicle information includes system configuration and vehicle parameters of the propulsion system of the amphibious vehicle; According to the system configuration of the propulsion system of the amphibious vehicle and based on the principle of computational fluid dynamics, the propulsion system of the amphibious vehicle is calculated to obtain a thrust database of the amphibious vehicle; According to the vehicle parameters of the amphibious vehicle, based on rigid body dynamics and fluid dynamics theory, a water dynamics model of the amphibious vehicle is established; Establish environmental disturbance models based on aerodynamics, wave mechanics and ocean current dynamics theories; Based on the water dynamics model and environmental disturbance model of the amphibious vehicle, an integrated development environment tool is used to write a high-precision amphibious vehicle water dynamics simulation program code; Based on computational fluid dynamics, with the goal of improving the accuracy of amphibious vehicle simulation, the high-precision amphibious vehicle water dynamics simulation program code is optimized to obtain a simulation code; Combine the optimized simulation code with Unreal Engine to create a water sports simulation platform for amphibious vehicles in Unreal Engine.

2. The method for constructing a high-precision amphibious vehicle water sports simulation platform according to claim 1, characterized in that: The system configuration of the propulsion system of the amphibious vehicle is a dual-thruster system configuration.

3. The method for constructing a high-precision amphibious vehicle water sports simulation platform according to claim 2, characterized in that: According to the system configuration of the propulsion system of the amphibious vehicle and based on the principle of computational fluid dynamics, the propulsion system of the amphibious vehicle is calculated to obtain the thrust database of the amphibious vehicle, which specifically includes: According to the system configuration of the propulsion system of the amphibious vehicle, the motion equation of the viscous incompressible fluid is used to solve the external flow field of the propulsion pump; the motion equation of the viscous incompressible fluid is specifically: Where ρ is the fluid density, v is the velocity vector of the fluid at time t, is the Laplace operator, p is the pressure, F is the external force vector, and the constant μ is the dynamic viscosity coefficient.

4. The method for constructing a high-precision amphibious vehicle water sports simulation platform according to claim 3 is characterized in that: According to the system configuration of the propulsion system of the amphibious vehicle and based on the principle of computational fluid dynamics, the propulsion system of the amphibious vehicle is calculated to obtain the thrust database of the amphibious vehicle, which specifically includes: According to the system configuration of the propulsion system of the amphibious vehicle, the multi-coordinate sliding grid model and the RNG k-ε model are used to solve the eddy viscosity; the solution equation of the eddy viscosity is specifically: Where k is the turbulent kinetic energy, ε is the turbulent dissipation rate, c μ =0.

085.

5. The method for constructing a high-precision amphibious vehicle water sports simulation platform according to claim 4, characterized in that: According to the vehicle parameters of the amphibious vehicle, based on the rigid body dynamics and fluid dynamics theory, a water dynamics model of the amphibious vehicle is established, which specifically includes: Considering the amphibious vehicle as a rigid body and the NED coordinate system {n} as an inertial system, determining a velocity vector of the amphibious vehicle and an angular velocity vector of the amphibious vehicle relative to the NED coordinate system; According to the velocity vector and the angular velocity vector, the external force acting on the center of gravity of the rigid body is calculated by using Euler's first law; the formula for calculating the external force acting on the center of gravity of the rigid body is specifically: in, is the external force acting on the center of gravity, represents the time differential in the inertial system {i}, and the S function is the vector cross product, and are the velocity vectors of the center of mass of the rigid body relative to the inertial system {i} and the NED coordinate system {n}, respectively. and is the angular velocity vector of the rigid body relative to the inertial frame {i} and the NED coordinate frame {n}.

6. The method for constructing a high-precision amphibious vehicle water sports simulation platform according to claim 5, characterized in that: According to the vehicle parameters of the amphibious vehicle, based on the rigid body dynamics and fluid dynamics theory, a water dynamics model of the amphibious vehicle is established, which specifically includes: According to the formula , Calculate the motion of the center of mass of a rigid body; Among them, I 3×3 is the 3×3 identity matrix, 0 3×3 is a 3×3 zero matrix, is the external torque acting on the center of mass of the rigid body, I g is the rotational inertia matrix of the rigid body’s center of mass.

7. The method for constructing a high-precision amphibious vehicle water sports simulation platform according to claim 6, characterized in that: After calculating the motion of the rigid body's center of mass, also include: According to the equation of motion of the center of mass of a rigid body, based on the formula ， Determine the motion of any point on a rigid body; Where H is the transformation matrix, is the rigid body inertia matrix about the center of gravity CG, is the center of gravity vector, and are the linear velocity and angular velocity of the rigid body in the body coordinate system, and are the linear acceleration and angular acceleration of the rigid body in the body coordinate system, respectively; f and m are the external force and external torque.

8. The method for constructing a high-precision amphibious vehicle water sports simulation platform according to claim 1, characterized in that: The optimized simulation code is combined with the Unreal Engine to create an amphibious vehicle water sports simulation platform in the Unreal Engine, including: Based on the Unreal Engine, an initial model of an amphibious vehicle simulation platform is built; the initial model includes a body shell, tires, and suspension; The optimized simulation code is combined with the initial model of the amphibious vehicle simulation platform in the Unreal Engine, and the calculation results of the optimized simulation code are visualized using the Unreal Engine to obtain the amphibious vehicle dynamics simulation platform.

9. A high-precision amphibious vehicle water sports simulation platform construction system, characterized in that: include: An information acquisition module, used to acquire vehicle information of the amphibious vehicle; the vehicle information includes a system configuration and vehicle parameters of a propulsion system of the amphibious vehicle; A calculation module, configured to calculate the propulsion system of the amphibious vehicle according to the system configuration of the propulsion system of the amphibious vehicle and based on the principle of computational fluid dynamics, so as to obtain a thrust database of the amphibious vehicle; A model building module is used to establish a water dynamics model of the amphibious vehicle based on vehicle parameters of the amphibious vehicle and on the basis of rigid body dynamics and fluid dynamics theory; Information acquisition module, used to establish environmental disturbance models based on aerodynamics, wave mechanics and ocean current dynamics theories; A code writing module, used to write a high-precision amphibious vehicle water dynamics simulation program code based on the water dynamics model and environmental disturbance model of the amphibious vehicle using an integrated development environment tool; A code optimization module is used to obtain an optimized simulation code for the high-precision amphibious vehicle water dynamics simulation program code based on computational fluid dynamics with the goal of improving the simulation accuracy of the amphibious vehicle; A platform building module for combining optimized simulation code with Unreal Engine to create a water sports simulation platform for amphibious vehicles in Unreal Engine.

10. A high-precision amphibious vehicle water sports simulation platform construction system according to claim 9, characterized in that: Platform building blocks, including: The initial model building submodule is used to build an initial model of an amphibious vehicle simulation platform based on the Unreal Engine; the initial model includes a body shell, tires and suspension; The platform building submodule is used to combine the optimized simulation code with the initial model of the amphibious vehicle simulation platform in the Unreal Engine, and use the Unreal Engine to visualize the calculation results of the optimized simulation code to obtain the amphibious vehicle dynamics simulation platform.

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