Articulated commercial vehicle simulation platform construction method and device, medium and product

Abstract

The invention discloses an articulated commercial vehicle simulation platform construction method and device, a medium and a product, and relates to the technical field of vehicle simulation, and the method comprises the steps: constructing a dynamical model of an articulated commercial vehicle based on a Lagrange dynamics theory; based on the dynamical model of the articulated commercial vehicle, an integrated development environment tool is adopted, and simulation codes, supporting vectorization operation, of the dynamical model are written; based on the improved 4-order Runge-Kutta method, optimization iteration is carried out on the simulation code with the purpose of improving the code solving efficiency and the calculation precision, and the optimized simulation code is obtained; and combining the optimized simulation code with an unreal engine, and constructing the articulated commercial vehicle dynamics simulation platform in the unreal engine. According to the invention, a refined dynamics simulation platform of the articulated commercial vehicle can be constructed.

Description

Technical Field

[0001] The present application relates to the field of vehicle simulation technology, and in particular to a method, device, medium and product for constructing an articulated commercial vehicle simulation platform. Background Art

[0002] In recent years, the number of commercial vehicles in my country has increased, and articulated commercial vehicles have been widely used due to their high efficiency, low cost, energy saving and emission reduction. With the trend of vehicle electrification and intelligence, the control performance and intelligent driving level of commercial vehicles have been required to be higher, and product iteration and optimization rely on vehicle dynamics simulation platforms. Articulated commercial vehicles have various configurations and require a flexible, modular, and high-precision simulation platform to provide a reference for control algorithm verification, vehicle design, and development of control algorithms for extreme conditions.

[0003] At present, there are two main ways to build simulation platforms for articulated commercial vehicles: the first is to rely on foreign commercial software such as Adams Car, Trucksim, and TruckMaker for analysis; the second is to use Newtonian mechanics for vehicle dynamics modeling. However, articulated commercial vehicles have complex structures, a large number of tires, and difficulty in handling hinge points. Most of the models built by related research institutes ignore the movement of the wheels, concentrate the wheel mass on the vehicle body, and are greatly simplified, resulting in insufficient model accuracy. Summary of the invention

[0004] The purpose of this application is to provide a method, device, medium and product for constructing an articulated commercial vehicle simulation platform, which can construct a refined dynamics simulation platform for articulated commercial vehicles.

[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 an articulated commercial vehicle simulation platform, comprising:

[0007] Based on the Lagrangian dynamics theory, a dynamic model of an articulated commercial vehicle is constructed; the dynamic model consists of the dynamics of four parts: the sprung mass of the tractor, the unsprung mass of the tractor, the sprung mass of the trailer, and the unsprung mass of the trailer;

[0008] Based on the dynamics model of the articulated commercial vehicle, using an integrated development environment tool, writing simulation code supporting vectorized operations for the dynamics model;

[0009] Based on the improved 4th-order Runge-Kutta method, the simulation code is optimized and iterated to improve the code solving efficiency and calculation accuracy, and an optimized simulation code is obtained;

[0010] Combine the optimized simulation code with Unreal Engine to build an articulated commercial vehicle dynamics simulation platform in Unreal Engine.

[0011] In a second aspect, the present application provides a computer device, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement any one of the above-mentioned methods for constructing an articulated commercial vehicle simulation platform.

[0012] In a third aspect, the present application provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements any of the above-mentioned methods for constructing an articulated commercial vehicle simulation platform.

[0013] In a fourth aspect, the present application provides a computer program product, including a computer program, which, when executed by a processor, implements any one of the above-mentioned methods for constructing an articulated commercial vehicle simulation platform.

[0014] According to the specific embodiments provided in this application, this application discloses the following technical effects:

[0015] The present application provides a method, device, medium and product for constructing an articulated commercial vehicle simulation platform. First, based on the Lagrangian dynamics theory, a dynamic model of an articulated commercial vehicle is constructed. This model is composed of the dynamic characteristics of four key parts, namely the sprung mass of the tractor, the unsprung mass of the tractor, the sprung mass of the trailer and the unsprung mass of the trailer. Subsequently, based on this precise dynamic model, an integrated development environment tool is used to write a simulation code that supports vectorized operations. This step ensures that the code can efficiently and accurately simulate the dynamic behavior of the vehicle. In order to further improve the solution efficiency and calculation accuracy of the code, an improved 4th-order Runge-Kutta method is used to optimize the simulation code for multiple iterations. This process aims to reduce calculation errors and improve the accuracy and real-time performance of the simulation. Finally, the optimized simulation code is combined with the Unreal Engine, and a dynamic simulation platform for articulated commercial vehicles is built with the functional support of the Unreal Engine. The method based on the present application can construct a refined dynamic simulation platform for articulated commercial vehicles. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] 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.

[0017] Figure 1 This is an application environment diagram of a method for constructing an articulated commercial vehicle simulation platform in one embodiment of the present application;

[0018] Figure 2 A schematic diagram of a flow chart of a method for constructing an articulated commercial vehicle simulation platform provided in one embodiment of the present application;

[0019] Figure 3 A schematic diagram of an articulated commercial vehicle provided in accordance with an embodiment of the present application;

[0020] Figure 4 A flowchart of an articulated commercial vehicle dynamics simulation platform implementation provided by an embodiment of the present application;

[0021] Figure 5 An articulated commercial vehicle dynamics model framework provided in one embodiment of the present application;

[0022] Figure 6 A flow chart for solving an articulated commercial vehicle model provided in one embodiment of the present application;

[0023] Figure 7 A schematic diagram of the structure of a computer device provided in one embodiment of the present application. DETAILED DESCRIPTION

[0024] 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.

[0025] 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.

[0026] The method for constructing an articulated commercial vehicle simulation platform provided in the embodiment of the present application can be applied to Figure 1In the application environment shown, the terminal 102 communicates with the server 104 through a network. The data storage system can store data that the server 104 needs to process. The data storage system can be set up separately, integrated on the server 104, or placed on the cloud or other servers. The terminal 102 can send the articulated commercial vehicle parameters to be processed to the server 104. After receiving the articulated commercial vehicle parameters to be processed, the server 104 constructs a dynamic model of the articulated commercial vehicle based on the Lagrangian dynamics theory; the dynamic model consists of the dynamics of the tractor sprung mass, the tractor unsprung mass, the trailer sprung mass and the trailer unsprung mass; based on the dynamic model of the articulated commercial vehicle, an integrated development environment tool is used to write a simulation code supporting vectorized operations for the dynamic model; based on the improved 4th-order Runge-Kutta method, the simulation code is optimized and iterated to improve the code solving efficiency and calculation accuracy, and the optimized simulation code is obtained; the optimized simulation code is combined with the Unreal Engine to build an articulated commercial vehicle dynamics simulation platform in the Unreal Engine. The server 104 can feedback the obtained articulated commercial vehicle dynamics simulation platform to the terminal 102. In addition, in some embodiments, the method for constructing an articulated commercial vehicle simulation platform may also be implemented independently by the server 104 or the terminal 102. For example, the terminal 102 may directly construct a dynamic model for the articulated commercial vehicle parameters to be processed, or the server 104 may obtain the articulated commercial vehicle parameters to be processed from a data storage system and construct a dynamic model for the articulated commercial vehicle parameters to be processed.

[0027] The terminal 102 may be, but is not limited to, various desktop computers, laptop computers, smart phones, tablet computers, IoT devices, and portable wearable devices. The IoT devices may be smart speakers, smart TVs, smart air conditioners, smart vehicle-mounted devices, etc. The portable wearable devices may be smart watches, smart bracelets, head-mounted devices, etc. The server 104 may be implemented as an independent server or a server cluster consisting of multiple servers, or may be a cloud server.

[0028] In an exemplary embodiment, Figure 2 As shown, a method for constructing an articulated commercial vehicle simulation platform is provided. The method is executed by a computer device, and can be executed by a computer device such as a terminal or a server alone, or by a terminal and a server together. In the embodiment of the present application, the method is applied to Figure 1 The server 104 in the example is used as an example to illustrate the method, which includes the following steps 201 to 208. Among them:

[0029] Step 201, constructing a dynamic model of an articulated commercial vehicle based on Lagrangian dynamics theory; the dynamic model is composed of the dynamics of four parts: the sprung mass of the tractor, the unsprung mass of the tractor, the sprung mass of the trailer, and the unsprung mass of the trailer;

[0030] Step 202, based on the dynamic model of the articulated commercial vehicle, using an integrated development environment tool to write a simulation code supporting vectorized operation of the dynamic model;

[0031] Step 203, based on the improved fourth-order Runge-Kutta method, with the goal of improving code solving efficiency and calculation accuracy, the simulation code is optimized iteratively to obtain an optimized simulation code;

[0032] Step 204 , combining the optimized simulation code with the Unreal Engine to build an articulated commercial vehicle dynamics simulation platform in the Unreal Engine.

[0033] In some embodiments, when executing step 201, the specific steps may be as follows:

[0034] When constructing a dynamic model of an articulated commercial vehicle using Lagrangian dynamics theory, the key input parameters of the model are the steering wheel angle and the driving or braking torque of each wheel. The rotation of the tire is driven by the wheel torque and the longitudinal ground force. The core inputs of the tire model module include the rotational angular velocity of the wheel and the speed of the wheel center, and its output is accurate tire force and torque data.

[0035] The vertical motion of the unsprung mass is directly affected by the vertical force of the tire and the suspension force. In order to more accurately simulate the behavior of the hinge point, this embodiment regards it as a spring-damper system and calculates the magnitude of the articulation force based on the relative motion between the tractor and the trailer.

[0036] The overall motion state of the vehicle body is determined by multiple factors such as longitudinal and lateral tire forces, aerodynamic forces, suspension forces, and articulation forces. Figure 4 This modeling approach ensures a comprehensive and accurate description of the dynamic characteristics of articulated commercial vehicles.

[0037] In order to improve the computational efficiency, a vehicle dynamics model supporting vectorized computation is established using vectorized programming methods. Figure 3 As shown in the figure, it is the whole vehicle dynamics model framework, which includes the interaction between the body, suspension, unsprung mass and tire models of the tractor and trailer.

[0038] The dynamic behavior of a simplified vehicle composed of multiple rigid components is represented by a multi-degree-of-freedom vehicle model. The bodies of the tractor and trailer can move in the longitudinal, lateral and vertical directions, and rotate around the xyz axes. The 12 wheels have 12 rotational degrees of freedom, and due to the existence of the suspension system, the 12 wheels have 12 vertical degrees of freedom. A total of 36 degrees of freedom.

[0039] In the modeling process, this embodiment uses O-xyz to represent the earth coordinate system, O1-x1y1z1 to represent the tractor body coordinate system, O2-x2y2z2 to represent the trailer body coordinate system, and the generalized coordinates of multiple degrees of freedom are represented by vectors as follows:

[0040] q=[q t,bv T q t,bω T q t,uθ T q t,uz T q s,bv T q s,bω T q s,uθ T q s,uz T ]

[0041] q t,bv =[X t Y t Z t ] T

[0042]

[0043] q t,uθ =[θ t,u,fl θ t,u,fr θ t,u,ml θ t,u,mr θ t,u,rl θ t,u,rr ] T

[0044] q t,uz =[z t,u,fl z t,u,fr z t,u,ml z t,u,mr z t,u,rl z t,u,rr ] T

[0045] q s,bv =[X s Y s Zs ] T

[0046]

[0047] q s,uθ =[θ s,u,fl θ s,u,fr θ s,u,ml θ s,u,mr θ s,u,rl θ s,u,rr ] T

[0048] q s,uz =[z s,u,fl z s,u,fr z s,u,ml z s,u,mr z s,u,rl z s,u,rr ] T (1).

[0049] Where q represents the generalized coordinates of the vehicle model; subscript t represents the tractor, subscript s represents the trailer, and q bv represents the position vector of the center of mass of the vehicle body, X, Y, Z are the absolute displacements of the center of mass along the global coordinate system; q bω represents the rotation angle of the vehicle body’s center of mass, φ, ψ are the rotation angles of the vehicle body around the three axes of the global coordinate system; q uθ represents the angular velocity sequence generated by the rotation of the six tires on both sides, θ i represents the angular velocity of tire rotation; q uz represents the vertical displacement sequence of the six tires on both sides, z i Indicates the vertical displacement of the tire; the six tires are distinguished by subscripts, the subscripts u, fr represent the right tire of the first axle, u, fl represent the left tire of the first axle, u, mr represent the right tire of the second axle, u, ml represent the left tire of the second axle, u, rr represent the right tire of the third axle, and u, rl represent the left tire of the third axle.

[0050] The coordinates of the centers of the six tires of the tractor in the tractor body coordinate system in the x1-y1 plane are:

[0051]

[0052] In the formula, l t represents the longitudinal distance between the three axles of the tractor and the center of mass, w t Indicates the wheelbase of three axles. The subscript f indicates the first axle, m indicates the second axle, and r indicates the third axle.

[0053] Correspondingly, the coordinates of the centers of the six tires of the trailer in the trailer body coordinate system in the x2-y2 plane are:

[0054]

[0055] The unsprung mass, i.e. the relative vertical position of the tire in the vehicle coordinate system, can be expressed by its absolute coordinates, the vehicle roll angle, the pitch angle and the xy coordinates in the vehicle coordinate system, as shown below:

[0056]

[0057]

[0058] From formula (4), the vertical velocity of the unsprung mass in the vehicle body coordinate system can be expressed as:

[0059]

[0060]

[0061] The vehicle's 36-degree-of-freedom dynamics equation is derived based on Lagrangian dynamics, as shown below:

[0062]

[0063]

[0064] Where: T represents the kinetic energy of the system, Q t,b represents the generalized force on the sprung mass of the tractor, Q t,u represents the generalized force on the unsprung mass of the tractor, q t,b represents the generalized coordinates of the sprung mass of the tractor, q t,u The generalized coordinates of the tractor's six tires, i.e., the unsprung mass, include the tire angles and vertical positions; Q s,b represents the generalized force on the sprung mass of the trailer, Q s,u represents the generalized force on the unsprung mass of the trailer, q s,b The generalized coordinates of the sprung mass of the trailer, q s,u The generalized coordinates of the trailer's six tires, i.e. the unsprung mass, including the tire angles and vertical positions.

[0065] Among them, the calculation process of the system kinetic energy is introduced by taking the tractor as an example. The calculation process of the trailer system kinetic energy is exactly the same, so it will not be repeated here.

[0066] When calculating the kinetic energy of the sprung mass, the kinetic energy of the tire's lateral and longitudinal motion is taken into account, as shown in the following formula:

[0067]

[0068] Where: V t,b 、Vt,ui are the components of the generalized velocity of the tractor body and the unsprung mass velocity in the body coordinate system, M t,b 、M t,ui are the mass matrices of the tractor body and the unsprung mass, respectively. Through coordinate transformation and matrix calculation, the kinetic energy of the sprung mass can be expressed as:

[0069]

[0070] The kinetic energy of the unsprung mass is composed of the rotational and vertical motion of the tire, as shown below:

[0071]

[0072] Where: V t,uz ,ω t,u are the vertical speed and angular velocity of the six unsprung tires, M t,u , J t,u are the mass matrix and moment of inertia matrix of the unsprung mass, respectively. According to the matrix calculation, equation (10) can be converted into the form of generalized coordinates and generalized mass matrix:

[0073]

[0074]

[0075] like Figure 5 As shown in the figure, the vertical forces acting on the sprung mass (vehicle body) include the weight of the vehicle body, the suspension force, the vertical air resistance, and the vertical articulation force. The longitudinal forces include the lateral force generated between the tire and the ground, the longitudinal force and the component of the air resistance in the global coordinate system, and the longitudinal articulation force. The lateral force includes the component of the lateral and longitudinal forces of the tire on the ground, and the lateral articulation force. The three-axis torques include the torques of the above forces on the center of mass, the tire self-aligning torque, the air resistance torque, the reaction torque on the drive tire, and the torque at the articulation point.

[0076] When calculating the six-component force at the hinge, the hinge point is regarded as a spring-damper system in the direction of the six-component force. The six-component force at this point is determined by the relative displacement of the hinge point between the tractor and the trailer. First, the generalized coordinates of the hinge point in the tractor body coordinate system and the trailer body coordinate system are calculated:

[0077]

[0078]

[0079] Where: R, T are rotation and translation matrices respectively. The six-component force at the hinge point can be expressed as:

[0080]

[0081] Where: K, C are stiffness and damping coefficient matrices respectively.

[0082] The vertical force on the tire is composed of the tire's own weight and suspension force:

[0083] F t,z,i =F t,bs,i +m t,u,i g (16).

[0084] The longitudinal slip rate of the tire contact point with the ground is calculated as follows:

[0085]

[0086] Where: κ t,i is the tire slip rate, ω t,i is the angular velocity of the tire, v t,wx,i 、v t,wy,i are the longitudinal and lateral speeds of the wheel center respectively, and the calculation method is shown in the following formula:

[0087] v t,wx,i =v t,ux,i cosδ t,i +v t,uy,i sinδ t,i

[0088] v t,wy,i =-v t,ux,i sinδ t,i +v t,uy,i cosδ t,i (18).

[0089] Where: t,i is the tire turning angle, and the tire slip angle α t,i The calculation is as follows:

[0090]

[0091] Apply the tire magic formula to calculate tire longitudinal force, lateral force, self-aligning moment, rolling resistance moment, and yaw resistance moment.

[0092] The longitudinal force at the tire's contact point with the ground is described by the magic formula as follows:

[0093]

[0094] The lateral force at the point where the tire contacts the ground is described by the magic formula as follows:

[0095]

[0096] The tire overturning moment is calculated as follows:

[0097]

[0098] The tire rolling resistance torque is calculated as follows:

[0099]

[0100] The tire self-aligning torque is calculated as follows:

[0101] M t,z =-t(F y -S Vyk )+M zr +sF x (twenty four).

[0102] Among them, B x,i , B y,i is the stiffness factor, C x,i , C y,i is the shape factor, D x,i , D y,i is the peak factor, E x,i 、E y,i is the curvature factor, is the vertical offset, is the vertical deflection induced by the braking force, G xα,i , G yκ,i are the longitudinal and lateral weight coefficients of the combined working condition respectively; λ Mx is the overturning torque proportional factor, λ vMx is the vertical offset proportional factor of the flipping moment, Q sx1 is the tipping moment offset, Q sx2 is the camber-induced rollover coupling coefficient, Q sx3 is the lateral force induced overturning coupling coefficient, P pmx1 is the effect of expansion pressure on overturning moment; My is the rolling resistance torque proportional factor, Q sy1 is the rolling resistance torque coefficient, Q sy2 is the rolling resistance moment dependent on the longitudinal force, Q sy3 is the rolling resistance torque that depends on speed, Q sy4 is the rolling resistance moment dependent on the fourth power of speed, V ref is the reference speed; t is the tire trail, M zr is the residual self-aligning torque, and s is the combined slip ratio.

[0103] The suspension force is composed of spring force and damping force. When the stiffness and damping ratio are constant values, the suspension force can be expressed as:

[0104]

[0105] To calculate the air resistance, first calculate the air resistance slip angle. Assuming the air is still and the wind speed is 0, the air resistance slip angle is the vehicle's center of mass slip angle. The calculation method is as follows:

[0106]

[0107] Then, the air resistance coefficient is calculated by linear interpolation and cubic spline interpolation according to the air resistance side slip angle:

[0108]

[0109] Calculate the air resistance factor:

[0110]

[0111] In summary, put the above results into the calculation of air resistance:

[0112]

[0113] Where: A t,air is the frontal area of ​​the tractor, L t,air Calculate the length for the tractor's air resistance.

[0114] Based on the calculation of the tire force and suspension model above, the generalized force matrix of the sprung mass of the tractor is as follows:

[0115]

[0116] The forces acting on the unsprung mass of the tractor include suspension force, ground vertical force, and tire weight, and the torques acting on it include driving torque and tire rolling resistance torque. Its generalized force matrix is ​​expressed as:

[0117]

[0118] Similarly, the generalized force matrix of the trailer sprung mass and unsprung mass can be derived:

[0119]

[0120]

[0121] Based on force analysis and the principle of virtual work, the generalized force can be derived as shown in the following equation:

[0122]

[0123]

[0124]

[0125]

[0126] According to Lagrangian dynamics theory, the generalized equation of motion of the sprung mass of the tractor is as follows:

[0127]

[0128] The generalized equation of motion for the unsprung mass of the tractor is given by:

[0129]

[0130] The generalized equation of motion for the sprung mass of the trailer is as follows:

[0131]

[0132] The generalized equation of motion for the unsprung mass of the trailer is as follows:

[0133]

[0134] Among them, T t represents the system kinetic energy of the tractor t, q t,b represents the generalized coordinates of the sprung mass of the tractor, represents the first-order derivative of the generalized coordinates of the sprung mass of the tractor, represents the second-order derivative of the generalized coordinates of the sprung mass of the tractor, M t,gb The generalized mass matrix representing the sprung mass of the tractor, The first derivative of the generalized mass matrix representing the sprung mass of the tractor, Q t,b represents the generalized force on the sprung mass of the tractor, q t,u represents the generalized coordinates of the tractor's six tires, i.e., the unsprung mass, The first derivative of the generalized coordinates of the 6 tires, i.e. the unsprung mass, of the tractor; The second-order derivative of the generalized coordinates of the 6 tires of the tractor, i.e., the unsprung mass, M t,gu The generalized mass matrix representing the unsprung mass of the tractor, The first derivative of the generalized mass matrix representing the unsprung mass of the tractor, Q t,u is the generalized force on the unsprung mass of the tractor, T s represents the system kinetic energy of trailer s, q s,b represents the generalized coordinates of the sprung mass of the trailer, represents the first derivative of the generalized coordinates of the sprung mass of the trailer, The second derivative of the generalized coordinates representing the sprung mass of the trailer, M s,gb The generalized mass matrix representing the sprung mass of the semitrailer, The first derivative of the generalized mass matrix representing the sprung mass of the semitrailer, Q s,brepresents the generalized force on the sprung mass of the trailer, q s,u represents the generalized coordinates of the trailer's six tires, i.e., the unsprung mass, represents the first-order derivative of the generalized coordinates of the six tires of the trailer, i.e., the unsprung mass, The second-order derivative of the generalized coordinates of the six tires of the trailer, i.e., the unsprung mass, M s,gu The generalized mass matrix representing the unsprung mass of the semitrailer, The first derivative of the generalized mass matrix representing the unsprung mass of the semitrailer, Q s,u Represents the generalized force acting on the unsprung mass of the trailer.

[0135] The second-order differentials of all state variables can be obtained by using equations (35), (36), (37), and (38). The first-order differentials of the state variables can be obtained by integration, and the values ​​of all state variables can be obtained by calculation.

[0136] In some embodiments, when executing step 202, the specific steps may be as follows:

[0137] Based on the dynamic model of the articulated commercial vehicle, the generalized motion formula of the sprung mass of the tractor, the generalized motion formula of the unsprung mass of the tractor, the generalized motion formula of the sprung mass of the trailer and the generalized motion formula of the unsprung mass of the trailer in the dynamic model are compiled using Matlab or VisualStudio tools to obtain a simulation code supporting vectorized operations of the dynamic model.

[0138] Specifically, the steps for solving the simulation code supporting vectorized operation of the dynamic model are as follows: Figure 6 As shown:

[0139] First, determine the body parameters of the simulated vehicle, such as mass, moment of inertia, mechanism parameters, etc., determine the parameters of each submodule, such as air resistance calculation factor, tire structure parameters, magic formula constants, etc., and input the initial values ​​of each state of the vehicle, generalized coordinates, and speed;

[0140] According to the current vehicle state, the external forces and moments of each part are calculated through the suspension, air resistance, tire and other submodules. The calculation results of all external forces and moments are integrated and substituted into the vehicle body dynamics equation and tire dynamics equation to obtain the generalized acceleration of multiple state quantities.

[0141] At the same time, the differential equations of the intermediate quantities are obtained through the tire sub-model;

[0142] The above generalized acceleration and differential equations are integrated to obtain all state quantities at the next moment, which are used as initial values ​​for the next step of model solution.

[0143] The model is solved using the fourth-order Runge-Kutta integration method, as shown in equation (39).

[0144]

[0145]

[0146] Through the steps in this embodiment, a high-precision dynamic model simulation code for an articulated commercial vehicle can be obtained. In addition, the calculation results of the simulation code can be compared with the calculation results of the commercial software to verify the correctness of the constructed model.

[0147] In some embodiments, when executing step 203, the specific steps may be as follows:

[0148] For the dynamic model code developed in step 202, the code is optimized and iterated with the goal of improving computational efficiency, mainly considering the following aspects:

[0149] (1) The integration algorithm initially adopted in the calculation process in step 202 is the fourth-order Runge-Kutta method. Under certain working conditions, this integration method cannot be well applied. It is necessary to coordinate the calculation efficiency and calculation accuracy to improve the integration method (such as variable step size integration) to improve the calculation efficiency and calculation accuracy.

[0150] (2) The coefficient matrix of the dynamic differential equation derived in step 202 is of relatively large order, and the coefficient matrix is ​​considered during solution to improve solution efficiency.

[0151] (3) During the model calculation process, in order to obtain higher accuracy, some codes take a long time to solve. Consider simplifying the relevant calculation process through graph search, data-driven methods, etc., to achieve the goal of balancing solution efficiency and calculation accuracy.

[0152] Specifically, adjustment of the integration algorithm: In step 202, the integration algorithm initially selected is the classic 4th-order Runge-Kutta method. This method is known for its computational stability and certain accuracy, but its limitations gradually become apparent when faced with complex and changing working conditions. In particular, when high accuracy is required and computing resources are limited, the traditional fixed-step integration method may not be able to meet the dual requirements of computational efficiency and accuracy at the same time.

[0153] To this end, this embodiment introduces a variable step size integration strategy, such as the Adaptive Step Size Runge-Kutta Method. This method can dynamically adjust the step size according to the error estimate in the calculation process, thereby effectively reducing unnecessary calculation steps while ensuring the calculation accuracy, and significantly improving the calculation efficiency. In specific scenarios, the adaptive step size integration method can improve the calculation efficiency by about 30% to 50% compared to the fixed step size method.

[0154] Specifically, efficient processing of coefficient matrices: The coefficient matrices in dynamic differential equations are often of high order, and direct solution not only requires large amounts of computation but also easily introduces numerical errors. This embodiment fully considers the characteristics of the coefficient matrix during the optimization process, and effectively reduces the complexity of the solution through technical means such as matrix decomposition and sparsification.

[0155] For example, for large sparse matrices, this embodiment can use efficient algorithms such as LU decomposition and Cholesky decomposition to reduce the amount of calculation by using the sparsity of the matrix. At the same time, combined with parallel computing technology, the task of solving large matrices is assigned to multiple processors for parallel processing, further improving the solution speed.

[0156] Specifically, intelligent simplification of the solution process: In the process of model calculation, in order to pursue higher accuracy, some code segments often need to perform complex numerical calculations, which inevitably increases the solution time. In order to balance the solution efficiency and calculation accuracy, this embodiment introduces intelligent methods such as chart search and data drive to simplify the solution process.

[0157] The graph search method constructs a solution space graph of the problem and uses heuristic information to guide the search process to quickly find an approximate solution that meets the accuracy requirements. The data-driven method uses historical data to predict the solution to the current problem by training a machine learning model, thereby reducing the amount of calculation while ensuring accuracy.

[0158] In some embodiments, when executing step 204, the specific steps may be as follows:

[0159] A basic model of an articulated commercial vehicle simulation platform is built in Unreal Engine, including components such as the body shell, tires, and suspension, and a complete articulated commercial vehicle model is constructed based on the assembly of the above components.

[0160] The optimized dynamics simulation code obtained in step 203 is combined with the articulated commercial vehicle model in the Unreal Engine, and the calculation results of the simulation code are visualized using the Unreal Engine so that users can view the calculation results more clearly and conveniently. This forms an overall framework in which the self-written code calculates the dynamic behavior and the built Unreal Engine model displays the calculation results of the code.

[0161] Considering user friendliness during the integration process, the corresponding user interface is developed based on the Qt platform, including basic functions such as modular components, component parameter modification, motion process display, and mouse drag module. During the development process, corresponding external data interfaces are reserved so that the developed simulation platform can support the testing and verification of decision-making planning control algorithms, and finally build a fully autonomous and refined articulated commercial vehicle dynamics simulation platform.

[0162] In an exemplary embodiment, a computer device is provided. The computer device may be a server or a terminal. The internal structure diagram thereof may be as follows: Figure 7 As shown. The computer device includes a processor, a memory, an input / output interface (Input / Output, referred to as I / O) and a communication interface. The processor, the memory and the input / output interface are connected through a system bus, and the communication interface is connected to the system bus through the input / output interface. The processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program and a database. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The database of the computer device is used to store articulated commercial vehicle simulation platform data. The input / output interface of the computer device is used to exchange information between the processor and an external device. The communication interface of the computer device is used to communicate with an external terminal through a network connection. When the computer program is executed by the processor, a method for constructing an articulated commercial vehicle simulation platform is implemented.

[0163] Those skilled in the art will understand that Figure 7 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0164] In an exemplary embodiment, a computer device is further provided, including a memory and a processor, wherein a computer program is stored in the memory, and the processor implements the steps in the above-mentioned method embodiments when executing the computer program.

[0165] In an exemplary embodiment, a computer-readable storage medium is provided, storing a computer program, and when the computer program is executed by a processor, the steps in the above method embodiments are implemented.

[0166] In an exemplary embodiment, a computer program product is provided, including a computer program, and when the computer program is executed by a processor, the steps in the above method embodiments are implemented.

[0167] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, stored data, displayed data, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of relevant data must comply with relevant regulations.

[0168] Those of ordinary skill in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to the memory, database or other medium used in the embodiments provided in the present application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM may be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM).

[0169] The database involved in each embodiment provided in this application may include at least one of a relational database and a non-relational database. The non-relational database may include a distributed database based on blockchain, etc., but is not limited thereto. The processor involved in each embodiment provided in this application may be a general-purpose processor, a central processing unit, a graphics processor, a digital signal processor, a programmable logic device, a data processing logic device based on quantum computing, etc., but is not limited thereto.

[0170] In summary, this application has the following technical effects:

[0171] In the dynamic modeling of articulated commercial vehicles, this application considers the influence of tire movement on vehicle body characteristics, adopts the Lagrangian method and considers three-dimensional space rotation to improve the accuracy and applicability of the model. By independently writing the code and performing iterative optimization, the code achieves a balance between efficient calculation and accuracy. In addition, combining the code with the Unreal Engine provides a better visual interface and human-computer interaction experience, which is convenient for subsequent development and use.

[0172] 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.

[0173] 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 an articulated commercial vehicle simulation platform, characterized in that: include: Based on Lagrangian dynamics theory, a dynamic model of articulated commercial vehicles is constructed; The dynamic model consists of the dynamics of four parts: the sprung mass of the tractor, the unsprung mass of the tractor, the sprung mass of the trailer and the unsprung mass of the trailer; Based on the dynamics model of the articulated commercial vehicle, using an integrated development environment tool, writing simulation code supporting vectorized operations for the dynamics model; Based on the improved 4th-order Runge-Kutta method, the simulation code is optimized and iterated to improve the code solving efficiency and calculation accuracy, and an optimized simulation code is obtained; Combine the optimized simulation code with Unreal Engine to build an articulated commercial vehicle dynamics simulation platform in Unreal Engine.

2. The method for constructing an articulated commercial vehicle simulation platform according to claim 1, characterized in that: Based on Lagrangian dynamics theory, a dynamic model of an articulated commercial vehicle is constructed, including: According to the formula calculating the generalized motion of the sprung mass of the tractor vehicle in a dynamic model of the articulated commercial vehicle; Among them, T t represents the system kinetic energy of the tractor t, q t,b represents the generalized coordinates of the sprung mass of the tractor, represents the first-order derivative of the generalized coordinates of the sprung mass of the tractor, represents the second-order derivative of the generalized coordinates of the sprung mass of the tractor, M t,gb The generalized mass matrix representing the sprung mass of the tractor, The first derivative of the generalized mass matrix representing the sprung mass of the tractor, Q t,b It represents the generalized force acting on the sprung mass of the tractor.

3. The method for constructing an articulated commercial vehicle simulation platform according to claim 2, characterized in that: Based on Lagrangian dynamics theory, a dynamic model of an articulated commercial vehicle is constructed, including: According to the formula calculating the generalized motion of the unsprung mass of the tractor vehicle in a dynamic model of the articulated commercial vehicle; Among them, q t,u represents the generalized coordinates of the tractor's six tires, i.e., the unsprung mass, The first derivative of the generalized coordinates of the 6 tires, i.e. the unsprung mass, of the tractor; The second-order derivative of the generalized coordinates of the 6 tires of the tractor, i.e., the unsprung mass, M t,gu The generalized mass matrix representing the unsprung mass of the tractor, The first derivative of the generalized mass matrix representing the unsprung mass of the tractor, Q t,u It represents the generalized force acting on the unsprung mass of the tractor.

4. The method for constructing an articulated commercial vehicle simulation platform according to claim 3, characterized in that: Based on Lagrangian dynamics theory, a dynamic model of an articulated commercial vehicle is constructed, including: According to the formula calculating the generalized motion of the sprung mass of the trailer in a dynamic model of the articulated commercial vehicle; Among them, T s represents the system kinetic energy of trailer s, q s,b represents the generalized coordinates of the sprung mass of the trailer, represents the first derivative of the generalized coordinates of the sprung mass of the trailer, The second derivative of the generalized coordinates representing the sprung mass of the trailer, M s,gb The generalized mass matrix representing the sprung mass of the semitrailer, The first derivative of the generalized mass matrix representing the sprung mass of the semitrailer, Q s,b Represents the generalized force acting on the sprung mass of the trailer.

5. The method for constructing an articulated commercial vehicle simulation platform according to claim 4, characterized in that: Based on Lagrangian dynamics theory, a dynamic model of an articulated commercial vehicle is constructed, including: According to the formula calculating the generalized motion of the unsprung mass of the trailer in a dynamic model of the articulated commercial vehicle; Among them, q s,u represents the generalized coordinates of the trailer's six tires, i.e., the unsprung mass, represents the first-order derivative of the generalized coordinates of the six tires of the trailer, i.e. the unsprung mass, The second-order derivative of the generalized coordinates of the six tires of the trailer, i.e., the unsprung mass, M s,gu The generalized mass matrix representing the unsprung mass of the semitrailer, The first derivative of the generalized mass matrix representing the unsprung mass of the semitrailer, Q s,u Represents the generalized force acting on the unsprung mass of the trailer.

6. The method for constructing an articulated commercial vehicle simulation platform according to claim 5, characterized in that: Based on the dynamic model of the articulated commercial vehicle, an integrated development environment tool is used to write a simulation code supporting vectorized operation of the dynamic model, which specifically includes: Based on the dynamic model of the articulated commercial vehicle, the generalized motion formula of the sprung mass of the tractor, the generalized motion formula of the unsprung mass of the tractor, the generalized motion formula of the sprung mass of the trailer and the generalized motion formula of the unsprung mass of the trailer in the dynamic model are compiled using Matlab or VisualStudio tools to obtain a simulation code supporting vectorized operations of the dynamic model.

7. The method for constructing an articulated commercial vehicle simulation platform according to claim 1, characterized in that: The optimized simulation code is combined with Unreal Engine to build an articulated commercial vehicle dynamics simulation platform in Unreal Engine, including: Based on Unreal Engine, build an initial model of an articulated commercial vehicle simulation platform; the initial model includes a body shell, tires, and suspension; The optimized simulation code is combined with the initial model of the articulated commercial 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 articulated commercial vehicle dynamics simulation platform.

8. A computer device comprising: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement a method for constructing an articulated commercial vehicle simulation platform as described in any one of claims 1 to 7.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, a method for constructing an articulated commercial vehicle simulation platform according to any one of claims 1 to 7 is implemented.

10. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, a method for constructing an articulated commercial vehicle simulation platform according to any one of claims 1 to 7 is implemented.

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