A train full-scene collision energy collaborative dissipation spectrum series design method and system thereof

Abstract

This invention discloses a system for the systematic design of coordinated energy dissipation in train collisions across all scenarios. The method includes: constructing a three-dimensional rigid-flexible coupled dynamic model; conducting collision tests on the train using a full-scale collision test platform and decomposing the energy transfer path during the collision process based on the three-dimensional rigid-flexible coupled dynamic model, establishing longitudinal, lateral, and vertical energy flow equations respectively; setting an energy coordinated dissipation optimization objective function based on the vehicle body structural bearing limit and occupant injury threshold; solving for the energy distribution ratio of different energy-absorbing units using a multi-objective optimization algorithm to generate the optimal energy distribution scheme under all scenarios; and outputting the optimization result of the optimal energy distribution scheme under all scenarios to achieve coordinated energy dissipation and configurational stability maintenance of the train during the collision process. This application combines full-scale collision tests and multi-objective optimization methods to analyze and optimize energy distribution during train collisions.

Description

Technical Field

[0001] This invention relates to the field of train collision technology, specifically to a system for designing a spectrum of coordinated energy dissipation in train collisions across all scenarios. Background Technology

[0002] Train collision is an extremely complex and highly nonlinear process. Its collision evolution is not only related to the vehicle's own structure and rigidity-flexibility characteristics, but also affected by multiple factors such as track geometry, train speed, train formation, load status, and passenger distribution. It has high uncertainty and nonlinear coupling characteristics, making it difficult to accurately detect collision behavior.

[0003] Currently, traditional research methods mainly rely on a process of component-level testing, numerical model calibration, and collision scenario simulation. Energy dissipation analysis and collision response detection are conducted through local experiments and numerical simulations. However, existing collision test systems are mostly component-level or limited vehicle-level test platforms, lacking a test chain capable of systematically studying the collision response of full-size, multi-train formations in all scenarios. It is difficult to obtain complete longitudinal, lateral, and vertical energy transfer data. Furthermore, in collision safety design, existing methods rely heavily on experience or single-objective optimization, making it difficult to achieve coordinated dissipation and optimal matching of the overall train structure, energy absorption units, and occupant protection, thus limiting the improvement of train crashworthiness.

[0004] Therefore, there is an urgent need for a systematic design method for the coordinated dissipation of train collision energy in all scenarios, which can combine full-scale collision tests and multi-objective optimization methods to analyze and optimize the energy distribution during train collisions. Summary of the Invention

[0005] Purpose of the invention: In order to overcome the above shortcomings, the purpose of this invention is to provide a systematic design method and system for the coordinated dissipation of collision energy in all train scenarios.

[0006] To address the aforementioned technical problems, this invention provides a systematized design method for the coordinated dissipation of collision energy across all train scenarios, comprising: S1: Construct a three-dimensional rigid-flexible coupling dynamic model of the operating environment, vehicles, passengers, and multi-train formations; S2: A full-scale collision test platform with parallel bearing and instantaneous force measurement of branch resultant force is used to conduct collision tests on the train and the energy transfer path during the train collision process is decomposed according to the three-dimensional rigid-flexible coupling dynamic model, and the energy flow equations in the longitudinal, lateral and vertical directions are established respectively. S3: Based on the vehicle body structure load-bearing limit and occupant injury threshold, set the objective function for energy cooperative dissipation optimization; S4: Solve the energy distribution ratio of different energy absorption units through a multi-objective optimization algorithm to generate the optimal energy distribution scheme for the entire scenario; S5: Output and feedback the optimization results of the optimal energy distribution scheme in the whole scenario to realize the coordinated energy dissipation and configuration stability maintenance of the train during the collision process.

[0007] As a preferred embodiment of this application, the method for conducting a train collision test using a full-scale collision test platform with parallel bearing capacity and instantaneous force measurement of branch resultant force in step S2 includes: S21: Construct a multi-branch sensor network and set the maximum load capacity for each branch; S22: Assume the total force requirement is: ,in The maximum load-bearing capacity set for branch i; S23: When the peak local impact force exceeds the single detection range, the current is shunted by connecting multiple branches in parallel and the output signals of each branch are combined to generate a full-time domain impact force curve.

[0008] As a preferred embodiment of this application, the method for decomposing the energy transfer path in step S2 includes: S24: Set the overall kinetic energy of the train as: ,in For the total mass of the train, The speed at which the train collided; S25: During the collision, the overall kinetic energy of the train is decomposed into longitudinal energy dissipation, lateral energy dissipation, and vertical energy dissipation. ; S26: Define the energy distribution coefficients for longitudinal, transverse, and vertical directions, respectively. ,but: , , ,in ; S27: Real-time monitoring of wheel trajectory deviation, vehicle tilt angle, and anti-climb device force; dynamic control of energy flow direction by adjusting the ratio of longitudinal, lateral, and vertical energy distribution coefficients.

[0009] As a preferred embodiment of this application, the method for constructing the energy cooperative dissipation optimization objective function in step S3 includes: S31: Set constraints, including the load-bearing limit of the vehicle body structure and the occupant injury threshold; S32: Based on the energy dissipation path, the energy is decomposed into the end energy absorption unit, the middle car body energy absorption unit and the bogie energy absorption unit, and the energy distribution factor of the end energy absorption unit, the middle car body energy absorption unit and the bogie energy absorption unit is set. S33: Constructing the objective function for co-current energy dissipation optimization: ,in The total input collision energy, Each energy-absorbing unit absorbs energy. This represents the peak longitudinal acceleration of the vehicle body during the collision. As an indicator of occupant injury, As weight; Energy distribution factors, including Central vehicle body energy absorption unit and bogie energy absorption unit ,and ; The occupant injury index employs a multi-parameter comprehensive evaluation model, including: S331: Establish a weighted sum function for occupant chest compression, head acceleration, and neck torque parameters: ,in This refers to the compression of the occupant's chest. For the acceleration of the occupant's head, Neck torque of occupants These are the weighting coefficients; S332: During a train collision, monitor the occupant's chest compression, head acceleration, and neck torque parameters in real time, and calculate their weighted sum function value in real time; S333: Determine whether the real-time weighted sum function value exceeds the preset safety threshold. If so, reduce the risk of occupant injury by optimizing energy distribution and reducing deceleration peak value.

[0010] As a preferred embodiment of this application, the method for solving the energy distribution ratio of different energy-absorbing units in step S4 using a multi-objective optimization algorithm includes: S43: Use a genetic algorithm to iteratively optimize the energy allocation factor and remove individuals that do not meet the preset constraints in each iteration; S44: Use the Pareto front method to determine the non-dominated solution set of the train in frontal rigid wall collision, train collision and eccentric collision scenarios, and output the optimal energy allocation scheme.

[0011] As a preferred embodiment of this application, the method for achieving coordinated energy dissipation of the train during the collision process in step S5 includes: S51: Establish the coupled dynamic equations: ,in The system quality matrix, Here is the damping matrix. Here is the stiffness matrix. For displacement, External collision load; S52: Introduce an energy dissipation factor into the coupled dynamic equations. Then the energy absorbed by each energy-absorbing unit is: ,in The duration of the collision; S53: The energy absorbed by each energy-absorbing unit is calculated by numerical integration and it is determined in real time whether the preset threshold is exceeded. If so, the energy is redistributed by adjusting the triggering sequence of the structure, so that the total energy is dissipated evenly and local overload is avoided.

[0012] As a preferred embodiment of this application, the method for maintaining the configurational stability of the train during the collision process in step S5 includes: S54: Constraint force is provided through the coupler self-locking mechanism. This forms a longitudinal self-locking mechanism. ,in This is the longitudinal stiffness coefficient. This refers to the relative displacement. S54: Utilizing anti-deviation devices to provide lateral restoring force This forms a lateral anti-deviation mechanism. ,in This is the lateral stiffness coefficient. This is the lateral offset; S54: Provides vertical anti-climb force through anti-climb design. This forms a vertical anti-climb mechanism. ,in This is the vertical stiffness coefficient. This represents the vertical relative climbing displacement; S55: The constraint force, lateral restoring force and vertical anti-climbing force are superimposed to form a constraint vector, and the constraint vector is compared with the external impact force in real time. If the constraint vector is greater than or equal to the collision impact load, the train configuration remains stable.

[0013] As a preferred embodiment of this application, the method for maintaining train configuration stability in step S55 includes: S551: Real-time acquisition of train's longitudinal, lateral, and vertical acceleration and relative displacement, lateral offset and vertical relative climbing displacement; S552: Calculate the trajectory offset and construct the trajectory offset function: ,in These are the permissible longitudinal, lateral, and vertical limits, respectively; S553: ​​Determine whether the trajectory offset function is greater than the preset offset threshold. If so, enhance the constraint force and energy redistribution optimization. S554: Establishing a wheel-rail contact force model for trains using Hertz's nonlinear elastic contact theory: ,in Let be the wheel-rail contact constant, for a worn tread surface: ; This refers to the elastic compression between the wheel and rail. The radius of the train wheels; S555: Calculate the correction terms for traction and braking forces based on the longitudinal slip ratio. ,in Longitudinal slip ratio; S556: Combined with collision impact loads, the total force is generated: ,in For collision impact load; S557: Real-time determination of the relationship between the total force and the wheel-track adhesion limit of the train. When the total force exceeds the preset constraint threshold, the constraint force and energy redistribution optimization are enhanced.

[0014] As a preferred embodiment of this application, in step S4, the method further includes: S401: Define a speed range and calculate the overall kinetic energy of the train based on each speed registered within the speed range; S402: Based on the capacity of different energy-absorbing units, construct the following constraints: ,in The total number of speed ranges, Let J be the capacity of the j-th energy-absorbing unit. For speed level The proportion allocated to the j-th energy-absorbing unit; S403: Solve the unified allocation strategy under all speed levels through linear programming to form an energy dissipation scheme under the speed spectrum and automatically select the optimal allocation parameters according to the real-time monitored speed range during use.

[0015] This application also provides a system for classifying the coordinated dissipation of collision energy across all train scenarios using the above method, including: A full-scale collision test platform employing parallel load-bearing and instantaneous force measurement of branch resultant force; The coupling model construction module is used to build a three-dimensional rigid-flexible coupled dynamic model of the operating environment, vehicles, passengers, and multi-train formations. The collision simulation decomposition module is used to conduct collision tests on trains using a full-size collision test platform with parallel bearing and instantaneous force measurement of branch resultant force, and to decompose the energy transfer path during the train collision process according to the three-dimensional rigid-flexible coupling dynamic model, and establish the energy flow equations in the longitudinal, lateral and vertical directions respectively. The target optimization allocation module is used to set the energy cooperative dissipation optimization objective function by combining the vehicle body structure bearing limit and the occupant injury threshold; and to solve the energy allocation ratio of different energy absorption units through a multi-objective optimization algorithm to generate the optimal energy allocation scheme in the whole scenario. The optimized output module is used to output and feedback the optimization results of the optimal energy distribution scheme in the whole scenario, so as to realize the coordinated energy dissipation and configuration stability of the train during the collision process.

[0016] The technical solution described in this application has the following advantages over the prior art: 1. By introducing multi-rigid-body dynamics, multi-flexible-body dynamics and the finite element method, a three-dimensional rigid-flexible coupled dynamic model of the operating environment-vehicle-crew-multi-train was established. It can not only reflect the local nonlinear deformation of the car body, bogie and energy-absorbing elements, but also describe the kinematic and dynamic response of the overall train formation, overcoming the problems of low calculation efficiency and narrow applicability of existing single rigid-body or finite element models.

[0017] 2. This platform achieves millisecond-level resolution acquisition of 8,000-ton impact force through multi-branch sensor shunt measurement and signal synthesis, avoiding the saturation distortion problem caused by insufficient range of traditional single sensors.

[0018] 3. By using genetic algorithms and Pareto frontier methods, the optimal energy allocation schemes at different speed levels are obtained, and a unified energy dissipation scheme covering the entire speed spectrum is generated using linear programming methods. This ensures that the train can maintain optimal energy allocation efficiency under complex conditions such as high speed, low speed, train collision, and eccentric collision, overcoming the limitation of existing technologies that optimize energy allocation only for a single working condition.

[0019] 4. This application introduces a multi-parameter comprehensive occupant injury assessment model that integrates chest compression, head acceleration, and neck torque, calculates occupant injury indicators in real time, and incorporates them into the energy distribution optimization objective function; by reducing the peak longitudinal deceleration and dynamically adjusting the energy flow direction, it avoids the severe impact of local energy concentration on the occupant, thereby reducing the risk of occupant injury.

[0020] 5. This application constructs a three-dimensional configuration stability maintenance mechanism through longitudinal self-locking, lateral anti-deviation and vertical anti-climb constraints, and introduces a trajectory deviation function and Hertz nonlinear wheel-rail contact model for real-time monitoring and feedback. When trajectory deviation or adhesion limit exceedance is detected, the constraint force is automatically strengthened and the energy distribution scheme is adjusted, thereby effectively preventing secondary disasters such as car climbing and derailment, and ensuring the overall stability of the train during the collision process. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0022] Figure 1 This is a flowchart illustrating the systematized design method for the coordinated dissipation of collision energy across all train scenarios provided in this embodiment of the invention.

[0023] Figure 2 This is a schematic diagram of the rigid body motion definition provided in an embodiment of the present invention.

[0024] Figure 3 This is a schematic diagram of two rigid bodies connected by an arbitrary motion hinge, provided in an embodiment of the present invention.

[0025] Figure 4 This is a partial schematic diagram of the train rigid-flexible coupling collision dynamics model provided in an embodiment of the present invention.

[0026] Figure 5 This is a schematic diagram of the full-size collision test platform provided in an embodiment of the present invention.

[0027] Figure 6 This is a flowchart illustrating the method for conducting a train collision test according to an embodiment of the present invention.

[0028] Figure 7 This is a schematic diagram of the collision force and time curves provided in an embodiment of the present invention.

[0029] Figure 8 This is a flowchart illustrating the energy transfer path decomposition method provided in an embodiment of the present invention.

[0030] Figure 9 This is a flowchart illustrating the method for constructing an energy cooperative dissipation optimization objective function provided in an embodiment of the present invention.

[0031] Figure 10 This is a flowchart illustrating the method for solving the energy allocation ratio of different energy-absorbing units using a multi-objective optimization algorithm provided in this embodiment of the invention.

[0032] Figure 11 This is a flowchart illustrating the method for coordinated energy dissipation during a train collision provided in an embodiment of the present invention.

[0033] Figure 12 This is a flowchart illustrating the method for maintaining the configuration stability of a train during a collision, as provided in an embodiment of the present invention.

[0034] Figure 13 This is a flowchart illustrating the method for maintaining train configuration stability provided in an embodiment of the present invention.

[0035] Figure 14 This is a schematic diagram of the train collision trajectory preservation effect provided in an embodiment of the present invention.

[0036] Figure 15 This is a flowchart illustrating the method for setting up an energy dissipation scheme under the velocity spectrum provided in this embodiment of the invention.

[0037] Figure 16 This is a schematic diagram of the module connection of the train full-scenario collision energy collaborative dissipation spectrum system provided in the embodiment of the present invention. Detailed Implementation

[0038] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0039] Railway transportation boasts advantages such as high transport capacity, low cost, minimal susceptibility to natural disasters, energy efficiency, and safety and environmental friendliness, playing a vital role in the transportation system and serving as its main artery. Although the probability of railway vehicle accidents is relatively low, the threats and damage to life and property caused by such accidents are enormous.

[0040] In recent years, with the continuous development of railway technology, the probability of railway accidents has been greatly reduced. However, railway accidents are still difficult to completely avoid. Therefore, while actively taking various proactive protective measures to minimize the occurrence of train accidents, it is also particularly important to improve the safety protection performance of trains in the event of an accident and reduce the degree of damage to people and property.

[0041] Passive safety protection technology for trains refers to safety protection measures for personnel and property when a train collision occurs. It is also known as secondary safety protection measures. It mainly involves adding impact energy-absorbing devices to the ends of the train. When a collision occurs, the energy-absorbing devices deform in an orderly and controllable manner to absorb the impact kinetic energy of the train, protecting the survival space of the driver and passengers from being destroyed. At the same time, it controls the deceleration of the train during the collision within a tolerable range, thereby minimizing personal and property losses.

[0042] Currently, existing research methods mainly rely on a process of component-level testing, numerical model calibration, and collision scenario simulation. Energy dissipation analysis and collision response detection are conducted through local experiments and numerical simulations. However, existing collision test systems are mostly component-level or limited vehicle-level test platforms, lacking a test chain capable of systematically studying the collision response of full-size, multi-train formations in all scenarios. This makes it difficult to obtain complete longitudinal, lateral, and vertical energy transfer data. Furthermore, in collision safety design, existing methods rely heavily on experience or single-objective optimization, making it difficult to achieve coordinated dissipation and optimal matching between the overall train structure, energy-absorbing units, and occupant protection, thus limiting the improvement of train crashworthiness.

[0043] Therefore, the above problem remains unresolved. (Refer to...) Figure 1 As shown in some embodiments of this application, this application provides a systematized design method for the coordinated dissipation of collision energy across all train scenarios, the method comprising: S1: To achieve a realistic reproduction of the train collision process and an accurate characterization of the energy dissipation mechanism, this application establishes a three-dimensional rigid-flexible coupled dynamic model of the operating environment, vehicles, passengers, and multi-train formations. This model comprehensively considers multi-rigid-body system dynamics, multi-flexible-body system dynamics, and the finite element method, and can fully describe the kinematic response, structural deformation, and energy transfer laws of the train and its key components during the collision process.

[0044] Kinematics of multi-rigid-body systems: The motion of a rigid body can be defined by a local coordinate system. The position of the origin relative to the reference coordinate system (X,Y,Z) and the orientation of the local coordinate system relative to the reference coordinate system are used to determine the coordinate system. Figure 2 As shown, the definition Let be the position vector of the origin of the rigid body's local coordinate system relative to the origin of the reference coordinate system. The direction of the rigid body's local coordinate system relative to the reference space can be expressed by the direction cosine matrix. This means that if a rigid body i From the origin of the local coordinate system to the rigid body i The vector of any point P on is Then the position vector of that point in the reference coordinate system space It can be represented as: Write it in matrix form: , where the matrix and They are vectors and The column matrix is ​​composed of components relative to the reference coordinate system. From vector Components relative to the rigid body's local coordinate system. Direction cosine matrix. For matrix To matrix The transformation matrix. Therefore, the position vector. The first derivative of the formula with respect to time is: , where vector Let be the angular velocity vector of rigid body i. Let the position vector... Taking the second derivative of the formula with respect to time, we get: .

[0045] refer to Figure 3 As shown, two rigid bodies are connected by an arbitrary kinematic hinge. These two bodies are defined as i and j, respectively, where rigid body i is the parent body and rigid body j is the child body. The motion of child body j is described relative to its connected parent body i. The motion of the hinge is determined by the positional degrees of freedom of the hinge. The degrees of freedom of the hinge are represented in the column matrix. middle.

[0046] To describe the subbody j Relative to the parent body i For motion, MADYMO defines a hinged coordinate system for each rigid body. The hinged coordinate system is fixed on the volume. Assume the matrix... and Representing the body i Harmony j If the local coordinate system direction is such that the matrix is... sum matrix The transformation relationship can be expressed as: ,in, The direction cosine matrix is ​​used to represent the volume. i The orientation of the upper hinge coordinate system relative to the local coordinate system is independent of time. The direction cosine matrix represents the volume. j The hinge coordinate system on the body i The direction of the upper hinge coordinate system represents the hinge position degree of freedom. The function.

[0047] vector (body j The position vector of the origin of the local coordinate system relative to the reference coordinate system and the vector (body iThe relative relationship between the position vector of the origin of the local coordinate system and the position vector of the reference coordinate system can be expressed by the following formula: ,in For body i The position vector of the origin of the upper hinge coordinate system relative to the origin of the local coordinate system; For body j The position vector of the origin of the upper hinge coordinate system relative to the origin of the local coordinate system; For body i From the origin of the upper hinge coordinate system to the volume j The position vector of the origin of the upper hinge coordinate system; d ij For relative to the body i The component matrix of the hinge coordinate system represents the degrees of freedom of the hinge positions. The function.

[0048] The above matrix is ​​applied continuously to all individuals connected to the reference space. sum matrix Transformation formulas and vectors With vector The relative relationships between them are obtained until the position and orientation of all local coordinate systems relative to the reference coordinate system are obtained. Taking the first derivative of the above equation with respect to time, the angular velocity and linear velocity of the rigid body can be obtained, and their expressions are: , ,in For body j Relative to body i The angular velocity vector; by further differentiating relative to time, the angular acceleration and linear acceleration of the rigid body can be obtained.

[0049] Dynamics of multi-rigid-body systems: According to Newton's laws, any particle in a point-body system... k The relationship between the forces acting on the body and the motion can be expressed as: ,in and These represent the active external force and the constraint reaction force, respectively. Taking the vector dot product of the above equation with the virtual velocity of the mass and summing it over all masses, we get: This is called the general equation of dynamics for a point mass system. If the constraints on the system are all ideal constraints, since the virtual power done by the reaction forces of ideal constraints is zero, it can be simplified to... For a single rigid body, its dynamic equations can be expressed as: , ,in m For rigid body mass, Let the radius vector be the center of mass of the rigid body relative to the reference origin. It is the acceleration due to gravity. Represents the net external force acting on a rigid body. Let be the moment of inertia tensor of the rigid body. Rigid body central angular velocity, The net external torque acting on a rigid body about its center of mass.

[0050] A multi-rigid-body system can be viewed as a point-mass system; therefore, the general equations of dynamics for point-mass systems still hold. Furthermore, the entire system can be considered as composed of sub-point-mass systems defined by individual rigid bodies; thus, the general equations of dynamics for multi-rigid-body systems can be obtained: The above formula can be further simplified to: , where q is the position vector, M is the system mass matrix, and F is the generalized force.

[0051] The system constraint equations are: The velocity constraint equation derived from the aforementioned constraint equation is: ,in ; To constrain the Jacobian matrix, according to the equation: Therefore, the system's virtual velocity The equation should be satisfied: The above equation shows that the system's virtual velocity is related to... Each column vector is orthogonal, therefore Any linear combination of column vectors must also be orthogonal to the system's imaginary velocity. It can also be deduced that any column vector orthogonal to the system's imaginary velocity must be... A linear combination of column vectors, therefore , Let be the Lagrange multiplier. Taking the reciprocal of the time interval for the velocity constraint equations yields the acceleration constraint equations derived from them. =0, combining them yields the dynamic equations of the constrained system: .

[0052] Dynamics of a multi-flexible-body system: The components in a multi-flexible-body system can be considered as a system of sub-particles, and its virtual power can be written as: Among them, objects speed ,in Let be the velocity at the origin of the object's local coordinate system. Angular velocity, Angular acceleration, The generalized force acting on an object. Let be the generalized mass matrix of the object.

[0053] The virtual power of the entire system This is the sum of the virtual power of each component. According to general principles of dynamics, the virtual power equation for a multi-flexible-body system is: It forms the basis for deriving the dynamics of multi-flexible body systems.

[0054] When a multibody system has a tree-like structure and the friction in the hinges is negligible, the generalized coordinates of the system are independent, and the generalized external forces are also known functions of the system's state variables. Such a system is called a simple multibody system.

[0055] By modifying the inertia of the inner object and the external forces of the end object, the system's virtual power equation can be transformed into: This has the same form as the virtual power equation for a multi-body system containing n-1 objects, which is equivalent to reducing the original system by one object. Therefore, by continuously performing the above operations, a multi-flexible-body system containing n objects can be reduced to a system with only one object. It can be proven that there is a recursive relationship between the generalized accelerations of the objects; after determining the generalized acceleration of one object, the generalized accelerations of other objects in the system can be calculated sequentially in ascending order.

[0056] For complex systems, one hinge of the loop in the multibody system can be cut off, the constraint reaction force can be regarded as the external force of the hinge point, and the non-ideal constraint reaction force that may exist in the system can also be regarded as the external force of the system. Any multibody system can be simplified into a tree-like multibody system with only one ideal constraint.

[0057] Fundamental Equations of the Finite Element Method: The basic idea of ​​the finite element method is to discretize the continuum to obtain a discrete numerical model. After discretizing a continuous structure using the finite element method, its numerical model can be obtained, and the equations of motion can be written in the following form: ,in M , D and K These are the mass, damping, and stiffness matrices, respectively. The applied external load vector, These are the acceleration / displacement and velocity vectors of the nodes, respectively. D The matrix is ​​composed of the mass and stiffness matrices of all elements, assuming the damping is: ,in and The damping coefficient is... It is a function of time and When the equilibrium equation is reached, it can be written as: ,in It is called the nodal internal force vector.

[0058] The central difference algorithm is mainly used to solve the finite element model. The main calculation relationships of the fixed-time-step central difference method are as follows: , subscript , , , Corresponding time points ,t, and Where t is the current time point, substituting the central difference equation into the equation of motion yields: ,in , .

[0059] In the actual modeling, this application uses the MADYMO collision simulation software, coupling the finite element method with the multi-rigid-body dynamics method. Specifically, the finite element method is used to model the vehicle body structure, bogie, energy-absorbing components, etc., to accurately describe material nonlinearity and structural deformation. (Refer to...) Figure 4 As shown, multi-rigid-body modeling is used for occupant dummies, seats, hook-and-response devices, etc., to improve computational efficiency; under the rigid-flexible coupling framework, the interaction between environment, vehicle and occupant is solved simultaneously.

[0060] MADYMO boasts powerful finite element collision analysis capabilities. For the finite element method, the correctness of the material model selection directly impacts the accuracy of collision simulation results. MADYMO offers a rich set of material models, including elastic materials, elasto-plastic materials, foams and biological tissues, and ply stacking sequences, meeting diverse collision simulation needs.

[0061] S2: A full-scale collision test platform with parallel bearing and instantaneous force measurement of branch resultant force is used to conduct collision tests on the train, and the energy transfer path during the train collision process is decomposed according to the three-dimensional rigid-flexible coupling dynamic model, and the energy flow equations in the longitudinal, lateral and vertical directions are established respectively.

[0062] The full-scale collision test platform for parallel bearing and instantaneous force measurement of branch results includes a rigid wall, a test track, a train operation drive system, and a multi-branch sensor network. The rigid wall is used to simulate immovable obstacles; the track ensures the straightness and stability of the train test operation; the drive system provides the train with a set speed; and the multi-branch sensor network is used for high-precision measurement of transient impact force. To avoid the failure of a single sensor under high impact, the platform adopts a multi-branch parallel force measurement method. During the test, the electrical signals output by each branch are synchronously acquired, low-pass filtered, and time-domain aligned to ultimately form a composite impact force curve.

[0063] Specifically, refer to Figures 5 to 7As shown, in step S2, the method for conducting a collision test on the train using a full-scale collision test platform with parallel load and instantaneous force measurement of branch resultant force includes: S21: Construct a multi-branch sensor network and set the maximum load capacity for each branch; S22: Assume the total force requirement is: ,in The maximum load-bearing capacity set for branch i The upper limit of the overall force measurement is given by n, where n is the number of sensor branches. S23: When the peak local impact force exceeds the single detection range, the current is shunted through multiple branches in parallel, and the electrical signals output by each branch are synchronously acquired and digitally filtered before being synthesized to generate a full-time domain impact force curve.

[0064] The above scheme achieves high-precision measurement of transient 8000-ton impact force, avoiding the distortion problem caused by over-range in traditional single-branch schemes.

[0065] refer to Figure 8 As shown, the method for decomposing the energy transfer path in step S2 includes: S24: Set the overall kinetic energy of the train as: ,in For the total mass of the train, This refers to the train collision speed.

[0066] S25: During the collision, the overall kinetic energy of the train is decomposed into longitudinal energy dissipation. Horizontal energy consumption and vertical energy consumption : .

[0067] S26: Define the energy distribution coefficients for longitudinal, transverse, and vertical directions, respectively. ,but: , , ,in .

[0068] S27: Real-time monitoring of wheel trajectory deviation, vehicle tilt angle, and anti-climb device force. Based on the real-time monitoring results, the ratio of longitudinal, lateral, and vertical energy distribution coefficients is adjusted so that longitudinal energy is preferentially dissipated by the end energy absorption device, lateral energy is dissipated by the anti-deviation structure, and vertical energy is absorbed by the anti-climb device and bogie structure.

[0069] Through the above steps, energy is rationally distributed in three dimensions, ensuring that the train not only dissipates energy sufficiently during the collision process, but also maintains a stable trajectory, thus avoiding secondary problems such as overtaking and derailment.

[0070] S3: Based on the vehicle body structure load-bearing limit and occupant injury threshold, set the objective function for optimizing energy co-dissipation.

[0071] Specifically, refer to Figure 9 and Figure 10 As shown, in step S3, to ensure that the train meets both structural safety requirements and occupant survival space and injury indicators during a collision, a multi-objective energy collaborative dissipation optimization model needs to be constructed. Specifically: S31: Set constraints, including the load-bearing limits of the vehicle body structure. And occupant injury threshold ,in This represents the maximum allowable stress in critical structural components. This represents the upper limit of the comprehensive occupant injury index.

[0072] S32: Based on the energy dissipation path, the energy is decomposed to the end energy absorption unit. Central vehicle body energy absorption unit and bogie energy absorption unit Furthermore, energy distribution factors are set for the train end energy absorption unit, the middle car body energy absorption unit, and the bogie energy absorption unit. These energy distribution factors include... Central vehicle body energy absorption unit and bogie energy absorption unit ,and .

[0073] S33: Constructing the objective function for co-current energy dissipation optimization: ,in The total input collision energy, Each energy-absorbing unit absorbs energy. This represents the peak longitudinal acceleration of the vehicle body during the collision. As an indicator of occupant injury, As weight; It is the energy distribution factor.

[0074] In some examples of this application, the occupant injury index in step S33 adopts a multi-parameter comprehensive evaluation model, and the method includes: S331: Establish a weighted sum function for occupant chest compression, head acceleration, and neck torque parameters: ,in This refers to the compression of the occupant's chest. For the acceleration of the occupant's head, Neck torque of occupants These are the weighting coefficients; S332: During a train collision, monitor the occupant's chest compression, head acceleration, and neck torque parameters in real time, and calculate their weighted sum function value in real time.

[0075] S333: Determine whether the real-time weighted sum function value exceeds the occupant injury threshold. If so, proceed to step S334: Dynamically adjust the energy allocation factor during the optimization process to reduce the risk of occupant injury by reducing the peak longitudinal deceleration and increasing the buffer path.

[0076] S4: Solve the energy distribution ratio of different energy absorption units through a multi-objective optimization algorithm to generate the optimal energy distribution scheme for the entire scenario.

[0077] Specifically, refer to Figure 11 As shown, the method for solving the energy distribution ratio of different energy-absorbing units using a multi-objective optimization algorithm in step S4 includes: S43: The energy allocation factor is iteratively optimized using a genetic algorithm (GA). The steps include population initialization, fitness calculation, selection, crossover, and mutation operations. In each iteration, vehicles that do not meet the load-bearing limits of the vehicle body structure are eliminated. And occupant injury threshold Individuals.

[0078] S44: During the convergence process, the Pareto front method is used to determine the non-dominated solution set of the train in frontal rigid wall collision, train collision and eccentric collision scenarios. Then, in multiple scenarios of frontal rigid wall collision, train collision and eccentric collision, the corresponding optimal energy distribution scheme is output to form a systematic design benchmark for energy cooperative dissipation in all scenarios.

[0079] By using the S3–S4 method, this application can minimize the risk of occupant injury while ensuring the structural strength and safety of the train, and automatically generate the optimal energy distribution scheme under various collision scenarios.

[0080] S5: Output and feedback the optimization results of the optimal energy distribution scheme in the whole scenario to realize the coordinated energy dissipation and configuration stability maintenance of the train during the collision process.

[0081] Specifically, refer to Figure 12 The method for achieving coordinated energy dissipation of the train during the collision process in step S5 includes: S51: Establish the coupled dynamic equations: ,in The system quality matrix, Here is the damping matrix. Here is the stiffness matrix. For displacement, The external collision load is used; the dynamic response of the train structure during the collision is comprehensively described by the coupled dynamic equations.

[0082] S52: Introduce an energy dissipation factor into the coupled dynamic equations. Then the energy absorbed by each energy-absorbing unit is: ,in For the duration of the collision, Velocity vector; energy dissipation factor It is used to characterize the energy utilization efficiency of different energy absorption units, and its value ranges from [0,1].

[0083] S53: The energy absorption of each energy-absorbing unit is solved in real time by numerical integration methods (such as the central difference method or the Newmark-β method) and it is determined in real time whether the energy dissipation of any energy-absorbing unit exceeds the preset threshold. If so, step S54 is executed: the energy is redistributed by changing the triggering order (such as prioritizing the activation of backup energy-absorbing units) to make the energy dissipation more uniform and avoid local overload or single-point failure.

[0084] refer to Figure 13 and Figure 14 As shown, the method for maintaining the configuration stability of the train during the collision process in step S5 includes: S54: Constraint force is provided through the coupler self-locking mechanism. This forms a longitudinal self-locking mechanism. ,in This is the longitudinal stiffness coefficient. This represents the relative displacement.

[0085] S54: Utilizing anti-deviation devices to provide lateral restoring force This forms a lateral anti-deviation mechanism. ,in This is the lateral stiffness coefficient. This represents the lateral offset.

[0086] S54: Provides vertical anti-climb force through anti-climb design. This forms a vertical anti-climb mechanism. ,in This is the vertical stiffness coefficient. This represents the vertical relative climbing displacement.

[0087] S55: The constraint force, lateral restoring force, and vertical anti-climbing force are superimposed to form a constraint vector: The constraint vector is compared with the external impact force in real time. If the constraint vector is greater than or equal to the collision impact load, the train configuration remains stable.

[0088] In some examples of this application, see reference Figure 11 As shown, the method for maintaining train configuration stability in step S55 includes: S551: Real-time acquisition of train's longitudinal, lateral, and vertical acceleration and relative displacement, lateral offset, and vertical relative climbing displacement.

[0089] S552: Calculate the trajectory offset and construct the trajectory offset function: ,in These are the permissible longitudinal, lateral, and vertical limits, respectively.

[0090] S553: ​​Determine whether the trajectory offset function is greater than the preset offset threshold. If so, enhance the constraint force and energy redistribution optimization.

[0091] S554: Establishing a wheel-rail contact force model for trains using Hertz's nonlinear elastic contact theory: ,in Let be the wheel-rail contact constant, for a worn tread surface: ; This refers to the elastic compression between the wheel and rail. This refers to the radius of the train wheels.

[0092] S555: Calculate the correction terms for traction and braking forces based on the longitudinal slip ratio. ,in It represents the longitudinal slip ratio.

[0093] S556: Combined with collision impact loads, the total force is generated: ,in This refers to the impact load from the collision.

[0094] S557: Real-time assessment of the relationship between the total force and the wheel-track adhesion limit of the train. When the total force exceeds the preset constraint threshold, it is determined that there is a risk to the trajectory stability. At this time, the constraint force is strengthened and the energy distribution strategy is optimized to ensure the stability of the train's running configuration.

[0095] In some embodiments of this application, reference is made to Figure 15 As shown, in step S4, the method further includes: S401: Define a speed range and calculate the overall kinetic energy of the train based on each speed registered within the speed range.

[0096] Specifically, the train operating speed range is divided into several discrete speed intervals. And define a representative speed within each speed range. This is called the speed class; then, based on the total mass of the train, the overall kinetic energy of the trains at that speed class is calculated: ,in Speed ​​level The total input collision energy is calculated. Therefore, this step establishes the energy demand benchmark under the velocity spectrum.

[0097] S402: At each speed level, considering the energy absorption capacity of the energy absorption devices at the train ends, the energy absorption units in the middle of the car body, and the energy absorption units on the bogies, let the energy capacity of the j-th energy absorption unit be denoted as . And energy distribution factor satisfy Then the energy constraint condition for each energy-absorbing unit is: ,in The total number of speed ranges, Let J be the capacity of the j-th energy-absorbing unit. For speed level The proportion allocated to the j-th energy-absorbing unit. Therefore, this constraint formula ensures that, at all speed levels, the energy distribution of any energy-absorbing unit does not exceed its design capacity, avoiding failure due to localized overload.

[0098] S403: Solve the unified allocation strategy under all speed levels through linear programming to form an energy dissipation scheme under the speed spectrum and automatically select the optimal allocation parameters according to the real-time monitored speed range during use.

[0099] Specifically, the objective function and constraints established in steps S401 and S402 are input into the linear programming model, and the optimization objective is defined as: , where n is the total number of energy-absorbing units. The physical meaning of this objective function is to minimize the deviation between the actual energy dissipation and the theoretical energy demand at different speed levels, thereby obtaining a consistent optimal allocation scheme.

[0100] In the actual solution process, the simplex method or the interior point method is used for linear programming iteration at each speed level. The corresponding optimal energy allocation factor is calculated below. This leads to the formation of the optimal energy dissipation scheme across the entire velocity spectrum.

[0101] During actual train operation or collision simulation, the system monitors the train speed in real time using onboard sensors and determines its speed range. When the detected speed is... At that time, automatically call the speed level The optimal energy allocation parameters are determined to achieve dynamic control of energy dissipation.

[0102] In some embodiments of this application, reference is made to Figure 16 As shown, this application also provides a system for classifying the coordinated dissipation of collision energy across all train scenarios using the above method, comprising: The coupling model construction module 201 is used to construct a three-dimensional rigid-flexible coupling dynamic model of the operating environment, vehicles, passengers, and multi-train formations. The collision simulation decomposition module 202 is used to conduct collision tests on trains using a full-size collision test platform with parallel bearing and instantaneous force measurement of branch resultant force, and to decompose the energy transfer path during the train collision process according to the three-dimensional rigid-flexible coupling dynamic model, and establish the energy flow equations in the longitudinal, lateral and vertical directions respectively. The target optimization allocation module 203 is used to set the energy cooperative dissipation optimization objective function by combining the vehicle body structure bearing limit and the occupant injury threshold; and to solve the energy allocation ratio of different energy absorption units through a multi-objective optimization algorithm to generate the optimal energy allocation scheme in the whole scenario. The optimized output module 204 is used to output and feedback the optimization results of the optimal energy distribution scheme in the whole scenario, so as to realize the coordinated energy dissipation and configuration stability of the train during the collision process.

[0103] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0104] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A train full-scenario crash energy co-dissipation spectrum-based design method, characterized in that, Includes the following steps: S1: Construct a three-dimensional rigid-flexible coupling dynamic model of the operating environment, vehicles, passengers, and multi-train formations; S2: A full-scale collision test platform with parallel bearing and instantaneous force measurement of branch resultant force is used to conduct collision tests on the train and the energy transfer path during the train collision process is decomposed according to the three-dimensional rigid-flexible coupling dynamic model, and the energy flow equations in the longitudinal, lateral and vertical directions are established respectively. S3: Based on the vehicle body structure load-bearing limit and occupant injury threshold, set the objective function for energy cooperative dissipation optimization; S4: Solve the energy distribution ratio of different energy absorption units through a multi-objective optimization algorithm to generate the optimal energy distribution scheme for the entire scenario; S5: Output and feedback the optimization results of the optimal energy distribution scheme in the whole scenario to realize the coordinated energy dissipation and configuration stability maintenance of the train during the collision process.

2. The systematized design method for coordinated dissipation of collision energy across all train scenarios according to claim 1, characterized in that, The method for conducting train collision tests using a full-scale collision test platform with parallel load-bearing and instantaneous force measurement of branch resultant force in step S2 includes: S21: Construct a multi-branch sensor network and set the maximum load capacity for each branch; S22: Assume the total force requirement is: ,in The maximum load-bearing capacity set for branch i, where n is the number of branches; S23: When the peak local impact force exceeds the single detection range, the current is shunted by connecting multiple branches in parallel and the output signals of each branch are combined to generate a full-time domain impact force curve.

3. The systematized design method for coordinated dissipation of collision energy across all train scenarios according to claim 2, characterized in that, The method for decomposing the energy transfer path in step S2 includes: S24: Set the overall kinetic energy of the train as: ,in For the total mass of the train, The speed at which the train collided; S25: During the collision, the overall kinetic energy of the train is decomposed into longitudinal energy dissipation, lateral energy dissipation, and vertical energy dissipation. ； S26: Define the energy distribution coefficients for longitudinal, transverse, and vertical directions, respectively. ,but: , , ,in ; S27: Real-time monitoring of wheel trajectory deviation, vehicle tilt angle, and anti-climb device force; dynamic control of energy flow direction by adjusting the ratio of longitudinal, lateral, and vertical energy distribution coefficients.

4. A systematized design method for coordinated dissipation of collision energy across all train scenarios, as described in claim 1 or 3, is characterized in that... The method for constructing the energy cooperative dissipation optimization objective function in step S3 includes: S31: Set constraints, including the load-bearing limit of the vehicle body structure and the occupant injury threshold; S32: Based on the energy dissipation path, the energy is decomposed into the end energy absorption unit, the middle car body energy absorption unit and the bogie energy absorption unit, and the energy distribution factor of the end energy absorption unit, the middle car body energy absorption unit and the bogie energy absorption unit is set. S33: Constructing the objective function for co-current energy dissipation optimization: ,in The total input collision energy, Each energy-absorbing unit absorbs energy. This represents the peak longitudinal acceleration of the vehicle body during the collision. As an indicator of occupant injury, As weight; Energy distribution factors, including Central vehicle body energy absorption unit and bogie energy absorption unit ,and ; The occupant injury index employs a multi-parameter comprehensive evaluation model, including: S331: Establish a weighted sum function for occupant chest compression, head acceleration, and neck torque parameters: ,in This refers to the compression of the occupant's chest. For the acceleration of the occupant's head, Neck torque of occupants These are the weighting coefficients; S332: During a train collision, monitor the occupant's chest compression, head acceleration, and neck torque parameters in real time, and calculate their weighted sum function value in real time; S333: Determine whether the real-time weighted sum function value exceeds the preset safety threshold. If so, reduce the risk of occupant injury by optimizing energy distribution and reducing deceleration peak value.

5. The systematized design method for coordinated dissipation of collision energy across all train scenarios according to claim 4, characterized in that, The method for solving the energy distribution ratio of different energy-absorbing units using a multi-objective optimization algorithm in step S4 includes: S43: Use a genetic algorithm to iteratively optimize the energy allocation factor and remove individuals that do not meet the preset constraints in each iteration; S44: Use the Pareto front method to determine the non-dominated solution set of the train in frontal rigid wall collision, train collision and eccentric collision scenarios, and output the optimal energy allocation scheme.

6. A systematized design method for coordinated dissipation of collision energy across all train scenarios, as described in claim 1 or 5, is characterized in that... The method for achieving coordinated energy dissipation of the train during the collision process in step S5 includes: S51: Establish the coupled dynamic equations: ,in The system quality matrix, Here is the damping matrix. Here is the stiffness matrix. For displacement, External collision load; S52: Introduce an energy dissipation factor into the coupled dynamic equations. Then the energy absorbed by each energy-absorbing unit is: ,in The duration of the collision; S53: The energy absorbed by each energy-absorbing unit is calculated by numerical integration and it is determined in real time whether the preset threshold is exceeded. If so, the energy is redistributed by adjusting the triggering sequence of the structure, so that the total energy is dissipated evenly and local overload is avoided.

7. The systematized design method for coordinated dissipation of collision energy across all train scenarios according to claim 6, characterized in that, The method for maintaining the train's configuration stability during the collision process in step S5 includes: S54: Constraint force is provided through the coupler self-locking mechanism. This forms a longitudinal self-locking mechanism. ,in This is the longitudinal stiffness coefficient. This refers to the relative displacement. S54: Utilizing anti-deviation devices to provide lateral restoring force This forms a lateral anti-deviation mechanism. ,in This is the lateral stiffness coefficient. This is the lateral offset; S54: Provides vertical anti-climb force through anti-climb design. This forms a vertical anti-climb mechanism. ,in This is the vertical stiffness coefficient. This represents the vertical relative climbing displacement; S55: The constraint force, lateral restoring force and vertical anti-climbing force are superimposed to form a constraint vector, and the constraint vector is compared with the external impact force in real time. If the constraint vector is greater than or equal to the collision impact load, the train configuration remains stable.

8. The systematized design method for coordinated dissipation of collision energy across all train scenarios according to claim 7, characterized in that, The method for maintaining train configuration stability in step S55 includes: S551: Real-time acquisition of train's longitudinal, lateral, and vertical acceleration and relative displacement, lateral offset and vertical relative climbing displacement; S552: Calculate the trajectory offset and construct the trajectory offset function: ,in These are the permissible longitudinal, lateral, and vertical limits, respectively; S553: ​​Determine whether the trajectory offset function is greater than the preset offset threshold. If so, enhance the constraint force and energy redistribution optimization. S554: Establishing a wheel-rail contact force model for trains using Hertz's nonlinear elastic contact theory: ,in Let be the wheel-rail contact constant, for a worn tread surface: ; This refers to the elastic compression between the wheel and rail. The radius of the train wheels; S555: Calculate the correction terms for traction and braking forces based on the longitudinal slip ratio. ,in Longitudinal slip ratio; S556: Combined with collision impact loads, the total force is generated: ,in For collision impact load; S557: Real-time determination of the relationship between the total force and the wheel-track adhesion limit of the train. When the total force exceeds the preset constraint threshold, the constraint force and energy redistribution optimization are enhanced.

9. The systematized design method for coordinated dissipation of collision energy across all train scenarios according to claim 4, characterized in that, In step S4, the method further includes: S401: Define a speed range and calculate the overall kinetic energy of the train based on each speed registered within the speed range; S402: Based on the capacity of different energy-absorbing units, construct the following constraints: ,in The total number of speed ranges, Let J be the capacity of the j-th energy-absorbing unit. For speed level The proportion allocated to the j-th energy-absorbing unit; S403: By solving a unified allocation strategy for all speed levels through linear programming, an energy dissipation scheme under the speed spectrum is formed, and during use, the optimal allocation parameters are automatically selected based on the real-time monitored speed range.

10. A train full-scenario collision energy cooperative dissipation spectrum system using the method of any one of claims 1-9, characterized in that, include: A full-scale collision test platform employing parallel load-bearing and instantaneous force measurement of branch resultant force; The coupling model construction module is used to build a three-dimensional rigid-flexible coupled dynamic model of the operating environment, vehicles, passengers, and multi-train formations. The collision simulation decomposition module is used to conduct collision tests on trains using a full-size collision test platform with parallel bearing and instantaneous force measurement of branch resultant force, and to decompose the energy transfer path during the train collision process according to the three-dimensional rigid-flexible coupling dynamic model, and establish the energy flow equations in the longitudinal, lateral and vertical directions respectively. The target optimization allocation module is used to set the energy cooperative dissipation optimization objective function by combining the vehicle body structure bearing limit and the occupant injury threshold; and to solve the energy allocation ratio of different energy absorption units through a multi-objective optimization algorithm to generate the optimal energy allocation scheme in the whole scenario. The optimized output module is used to output and feedback the optimization results of the optimal energy distribution scheme in the whole scenario, so as to realize the coordinated energy dissipation and configuration stability of the train during the collision process.

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