An Automatic Construction Method for the Mathematical Simulation Software Framework of an Aircraft

Abstract

The present invention provides a method for automatically constructing a mathematical simulation software framework for an aircraft, belonging to the technical field of system simulation, and comprising the following steps: S1: encapsulate each discipline model and store the information in a model library; S2: read a graphical simulation process description file; S3: perform DTD constraint verification on the file; if the file is invalid, execute S13; if it is valid, execute S4; S4: parse the file; S5: connect to the model library, if the connection fails, execute S13; if the connection is successful, execute S6; S6: obtain the information parsed in S3 from the model library; S7: check whether the input and output match; S8: if the connection rules are not met, execute S13; if they are met, execute S9; S9: determine the execution order of each model; S10: generate a basic simulation program framework; S11: add call codes for model initialization functions; S12: add call codes for model running functions to obtain a mathematical simulation software, solving the problem of slow framework construction speed in the prior art.

Description

Technical Field

[0001] The present invention belongs to the technical field of system simulation, and particularly relates to a method for automatically constructing a mathematical simulation software framework for an aircraft. Background Art

[0002] Modern aircraft design often involves multiple specialties such as overall design, aerodynamics, and control, with characteristics such as a large number of disciplinary models and complex system structures. When building a mathematical simulation software framework for such aircraft, it is necessary to first model numerous models one by one, and then arrange the simulation process and write corresponding simulation programs according to the data interaction relationships between the models. The existing simulation system development method has a large workload and low design efficiency. Since it is mostly designed for specific models of aircraft, it cannot be transplanted and does not have universality.

[0003] The existing methods for creating aircraft simulation software mainly include two methods: pure manual writing and adding user code to the framework. When creating an aircraft simulation software using the pure manual writing method, designers model each model used in the entire simulation system one by one, and then write a complete simulation program according to the input-output relationships between the models. When creating an aircraft simulation software using the method of adding user code to the framework, the aircraft simulation software design tool provides users with a set of basic simulation framework codes, and users add their own implementation codes at specified positions for the framework to call back.

[0004] In the existing methods for creating aircraft simulation software, the pure manual writing method has a large coding workload, high requirements for designers' coding and debugging levels, prolongs the design cycle, and increases the design and maintenance costs. The method of adding user code to the framework reduces the requirements for designers' levels to a certain extent and improves work efficiency, but it is difficult to ensure the universality of the framework, and since users cannot know the internal structure of the framework, it is not easy to perform simulation debugging.

[0005] At the same time, both of the existing two code generation methods for aircraft simulation software require users to write code manually, which is not conducive to improving the speed and automation of aircraft mathematical simulation software design.

[0006] In summary, in the existing design process of aircraft mathematical simulation software, users need to write code manually, the framework construction speed is slow, which limits the further improvement of the automation level, and improvement is needed. Summary of the Invention

[0007] The present invention provides a method for automatically constructing a mathematical simulation software framework for an aircraft, aiming to solve the problems that in the existing technology, users need to write code manually in the design process of aircraft mathematical simulation software, and the framework construction speed is slow.

[0008] The object of the present invention is achieved by the following technical solutions:

[0009] A method for automatically constructing a mathematical simulation software framework for an aircraft, comprising the following steps:

[0010] Step S1: Encapsulate each disciplinary model according to the interface requirements, and store the model and its interface information in the model library;

[0011] Step S2: Read the graphical simulation process description file;

[0012] Step S3: Perform DTD constraint verification on the simulation process description file; if the file is invalid, execute Step S13; if it is valid, execute Step S4;

[0013] Step S4: Parse the file to obtain the model connection information and attribute information;

[0014] Step S5: Connect to the model library; if the connection fails, execute Step S13; if the connection is successful, execute Step S6;

[0015] Step S6: Obtain the interface information of the model parsed in Step S3 from the model library;

[0016] Step S7: According to the model connection information in Step S4 and the model interface information in Step S6, check whether each model conforms to the connection rules, that is, whether the input and output match;

[0017] Step S8: If it does not conform to the connection rules, execute Step S13; if it conforms, execute Step S9;

[0018] Step S9: Determine the execution order of each model according to the model connection information obtained in Step S4;

[0019] Step S10: Generate a basic simulation program framework for the aircraft simulation system;

[0020] Step S11: According to the model execution order obtained in Step S9, the model attribute information obtained in Step S4, and the model interface information obtained in Step S6, add call codes for the model initialization function to the program framework in Step S10;

[0021] Step S12: According to the model execution order obtained in Step S9 and the model interface information obtained in Step S6, add call codes for the model running function to the program framework in Step S10;

[0022] So far, the automatic construction of the mathematical simulation software framework for the aircraft is completed, and a mathematical simulation software that can be directly run is obtained.

[0023] As a further optimization, the framework structure of the aircraft mathematical simulation software includes a projectile model, a Earth model, an atmosphere and wind field model, an attitude control dynamics model, an aerodynamic model, a strapdown inertial measurement unit model, a control network model, and a servo mechanism model; the internal parameters of the Earth model and the servo mechanism model can be modified. The internal parameters of the Earth model are the longitude, latitude, altitude, and launch azimuth of the launch point, and the internal parameters of the servo mechanism model are the limit values of the rudder deflection angle and the limit value of the rudder deflection angular velocity. The parameter values are set according to the simulation mission statement.

[0024] As a further optimization, the framework structure of the aircraft mathematical simulation software further includes one or several of an engine model, a seeker model, and an elastic model.

[0025] As a further optimization, in the framework structure of the aircraft mathematical simulation software, all models are encapsulated to have a unified external representation form and are stored in the model database. The model includes model inputs, model outputs, model attributes, a model initialization function, and a model running function. The meanings and functions of each part are as follows:

[0026] Model inputs: Used to receive data. The number of model inputs and the detailed information of the data types of each input are stored in the model library;

[0027] Model outputs: Used to output data. The number of model outputs and the detailed information of the data types of each input are stored in the model library;

[0028] Model attributes: Used to set the modifiable parameters inside the model;

[0029] Model initialization function: Used to implement the initialization operation of the model according to the attribute settings;

[0030] Model running function: Provides an interface for the implementation of the core functions of the model.

[0031] As a further optimization, in the framework structure of the aircraft mathematical simulation software, the number of inputs of the servo mechanism model is 3, and the data types of each input are float, float, and float respectively; the number of outputs of the servo mechanism model is 3, and the data types of each output are float, float, and float respectively; the attributes of the servo mechanism model are the limit values of the rudder deflection angle and the rudder deflection angular velocity, the number of attributes is 2, and the data types of each attribute are float and float respectively.

[0032] As a further optimization, in the framework structure of the aircraft mathematical simulation software:

[0033] The inputs of the projectile model are the geocentric radius vector of the launch point, initial parameters, atmospheric density, wind, centroid position, moment of inertia, aerodynamic coefficient, nozzle force, and moment; the outputs are position and attitude information;

[0034] The output of the Earth model is the geocentric radius vector of the launch point;

[0035] The input of the atmosphere and wind field model is position information; the output is atmospheric density and wind speed;

[0036] The input of the attitude control power model is the nozzle command; the output is the nozzle force and moment;

[0037] The input of the aerodynamic model is the flight state quantity and the rudder deflection angle; the output is the aerodynamic coefficient;

[0038] The input of the strapdown inertial measurement unit model is position and attitude information; the output is the navigation signal;

[0039] The input of the control network model is the navigation signal; the output is the rudder deflection command and the nozzle command;

[0040] The input of the servo mechanism model is the rudder deflection command; the output is the rudder deflection angle;

[0041] The input of the overall parameter model is mass; the output is the centroid position and the moment of inertia.

[0042] As a further optimization, the graphical simulation process description file adopts the XML format.

[0043] As a further optimization, the graphical simulation process description file adopts the Json format.

[0044] The beneficial technical effects achieved by the present invention are:

[0045] By parsing the graphical simulation software process, a directly executable system framework is automatically generated, realizing the automatic construction of the aircraft mathematical simulation software framework. The constructed simulation software framework can be directly run, and no code needs to be manually written by the user during the construction process. Compared with the prior art, it can effectively shorten the design cycle and improve the automation degree of the aircraft mathematical simulation software design. It solves the problems of numerous discipline models, complex system structures, and difficult simulation program writing in modern aircraft design, and the need for users to manually write code and slow framework building speed during the design process of the aircraft mathematical simulation software, and has prominent substantive features and significant progress. Description of the Drawings

[0046] Figure 1 It is a schematic diagram of the aircraft simulation system of one specific embodiment of the present invention;

[0047] Figure 2 It is a schematic diagram of the model interface of one specific embodiment of the present invention;

[0048] Figure 3 It is a flowchart of the automatic generation of the software framework of one specific embodiment of the present invention. Detailed Embodiments

[0049] The technical solution of the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present invention.

[0050] As Figure 1 shown, it is a typical structural block diagram of an aircraft mathematical simulation software, which contains multiple discipline models. It can be found by observation that each model has several inputs and outputs, and the inputs and outputs of each model are connected by signal lines to represent the data relationship between them. At the same time, some internal parameters of the model can be modified, which are referred to as model attributes here.

[0051] A specific embodiment of a method for automatically constructing an aircraft mathematical simulation software framework will be described by taking the Figure 1 structural block diagram of the aircraft mathematical simulation software shown as an example to illustrate its principle. The aircraft mathematical simulation software structure in this specific embodiment includes a projectile body model, an earth model, an atmosphere and wind field model, an attitude control power model, an aerodynamic model, a strapdown inertial measurement unit model, a control network model, and a servo mechanism model.

[0052] The inputs of the projectile body model are the geocentric radius vector of the launch point, initial parameters, atmospheric density, wind, centroid position, moment of inertia, aerodynamic coefficient, nozzle force and moment; the outputs are position and attitude information.

[0053] The output of the earth model is the geocentric radius vector of the launch point.

[0054] The inputs of the atmosphere and wind field model are position information; the outputs are atmospheric density and wind speed.

[0055] The input of the attitude control power model is the nozzle command; the output is the nozzle force and moment.

[0056] The inputs of the aerodynamic model are flight state variables and rudder deflection angles; the output is the aerodynamic coefficient.

[0057] The inputs of the strapdown inertial measurement unit model are position and attitude information; the output is the navigation signal.

[0058] The input of the control network model is the navigation signal; the outputs are rudder deflection commands and nozzle commands.

[0059] The input of the servo mechanism model is the rudder deflection command; the output is the rudder deflection angle.

[0060] The input of the overall parameter model is mass; the outputs are centroid position and moment of inertia.

[0061] Among them, the internal parameters of the earth model and the servo mechanism model can be modified. The internal parameters of the earth model are the longitude, latitude, altitude, and launch azimuth of the launch point, and the internal parameters of the servo mechanism model are the limit amplitude of the rudder deflection angle and the limit amplitude of the rudder deflection angular velocity. The parameter values are set according to the simulation task book.

[0062] It should be noted that the structure of the aircraft mathematical simulation software may also include an engine model, a seeker model, an elastic model, etc., which are determined according to the specific composition of the aircraft. It is based on the same idea as this specific embodiment and there is no substantial difference.

[0063] In order to automatically generate code based on the graphical simulation software structure block diagram, the models must be encapsulated to have a unified external representation form. For this reason, in this specific embodiment, each model is designed into the Figure 2 interface form shown and stored in the model database. The model includes model input, model output, model attributes, model initialization function, and model running function. The meanings and functions of each part are as follows:

[0064] Model input: Used to receive data. The number of model inputs and the detailed information such as the data type of each input are stored in the model library. The number of model inputs and the data type of each input are not limited and can be set according to actual needs. In this specific embodiment, the number of inputs of the servo mechanism model is 3, and the data types of each input are float, float, and float respectively.

[0065] Model output: Used to output data. The number of model outputs and the detailed information such as the data type of each input are stored in the model library. The number of model outputs and the data type of each input are not limited and can be set according to actual needs. In this specific embodiment, the number of outputs of the servo mechanism model is 3, and the data types of each output are float, float, and float respectively.

[0066] Model attributes: Used to set the modifiable parameters inside the model. The specific parameters are set according to actual needs. In this specific embodiment, the attributes of the servo mechanism model are the rudder deflection angle and the limit amplitude of the rudder deflection angular velocity. The number of attributes is 2, and the data types of each attribute are float and float respectively.

[0067] Model initialization function: Used to implement the initialization operation of the model according to the attribute settings.

[0068] Model running function: Provides an interface for the implementation of the core function of the model.

[0069] For the convenience of operation, in this specific embodiment, the graphical simulation software structure block diagram is stored in an XML file to describe the connection relationship between each model and the attribute information of the model. At the same time, the interface information of each model is stored in the model library. The graphical simulation software structure block diagram can also be stored in other hierarchical structure files such as Json, which has no substantial difference in this specific embodiment.

[0070] When automatically generating the simulation software framework, in this specific embodiment, first, the operation sequence and attribute information of the model are obtained by parsing the XML file. Then, the interface information of the model is obtained by accessing the model library. Then, the code for creating and calling the initialization function of each model and the code for executing the model function are sequentially created, and the automatic construction of the aircraft mathematical simulation software framework can be realized.

[0071] As Figure 3 shown, the method for automatically constructing the aircraft mathematical simulation software framework in this specific embodiment includes five steps: obtaining model connection information, obtaining model interface information, checking model connection rules, determining the model operation sequence, and code generation, which specifically include the following steps:

[0072] Step S1: Encapsulate each discipline model according to the interface requirements, and store the model and its interface information in the model library.

[0073] Step S2: Read the graphical simulation process description file. In this specific embodiment, the graphical simulation process description file is in XML format;

[0074] Step S3: Perform DTD constraint verification on the simulation process description file. If the XML file is invalid, execute Step S13; if it is valid, execute Step S4.

[0075] Step S4: Parse the XML file to obtain the model connection information and attribute information.

[0076] Step S5: Connect to the model library. If the connection fails, execute Step S13; if the connection is successful, execute Step S6.

[0077] Step S6: Obtain the interface information of the model parsed in Step S3 from the model library.

[0078] Step S7: According to the model connection information in Step S4 and the model interface information in Step S6, check whether each model conforms to the connection rules, that is, whether the input and output match.

[0079] Step S8: If it does not conform to the connection rules, execute Step S13; if it conforms, execute Step S9.

[0080] Step S9: Determine the execution order of each model according to the model connection information obtained in Step S4.

[0081] Step S10: Generate the basic simulation program framework of the aircraft simulation system.

[0082] Step S11: According to the model execution order obtained in step S9, the model attribute information obtained in step S4, and the model interface information obtained in step S6, add the call code for the model initialization function to the program framework in step S10.

[0083] Step S12: According to the model execution order obtained in step S9 and the model interface information obtained in step S6, add the call code for the model running function to the program framework in step S10.

[0084] So far, the automatic construction of the aircraft mathematical simulation software framework is completed, and a directly executable mathematical simulation software is obtained.

[0085] The beneficial technical effects achieved by this specific embodiment are as follows:

[0086] (1) Realize the automatic generation of directly executable framework code, reduce the technical level requirements for designers, and relieve the coding burden on designers.

[0087] (2) Effectively shorten the design cycle and improve the automation degree of the construction of the mathematical simulation software.

Claims

1. A method for automatically constructing a mathematical simulation software framework for an aircraft, characterized in that, The framework structure of the aircraft mathematical simulation software includes a projectile model, an earth model, an atmosphere and wind field model, an attitude control power model, an aerodynamic model, a strapdown inertial measurement unit (IMU) model, a control network model, and a servo mechanism model; The inputs of the projectile model are the geocentric radius vector of the launch point, initial parameters, atmospheric density, wind, centroid position, moment of inertia, aerodynamic coefficients, nozzle forces and moments; the outputs are position and attitude information; The output of the earth model is the geocentric radius vector of the launch point; The input of the atmosphere and wind field model is position information; The outputs are atmospheric density and wind speed; The input of the attitude control power model is the nozzle command; the outputs are nozzle forces and moments; The inputs of the aerodynamic model are flight state variables and rudder deflection angles; the output is the aerodynamic coefficient; The inputs of the strapdown IMU model are position and attitude information; The output is the navigation signal; The input of the control network model is the navigation signal; the outputs are rudder deflection commands and nozzle commands; The input of the servo mechanism model is the rudder deflection command; the output is the rudder deflection angle; The input of the overall parameter model is mass; the outputs are centroid position and moment of inertia; The internal parameters of the earth model and the servo mechanism model can be modified. The internal parameters of the earth model are the longitude, latitude, altitude, and launch azimuth of the launch point. The internal parameters of the servo mechanism model are the limit values of the rudder deflection angle and the limit value of the rudder deflection angular velocity. The parameter values are set according to the simulation task book; The method for automatically constructing the framework of the aircraft mathematical simulation software specifically includes the following steps: Step S1: Package each disciplinary model according to the interface requirements, and store the model and its interface information in the model library; Step S2: Read the graphical simulation process description file; Step S3: Perform DTD constraint verification on the simulation process description file; if the file is invalid, execute Step S13; if it is valid, execute Step S4; Step S4: Parse the file to obtain the model connection information and attribute information; Step S5: Connect to the model library. If the connection fails, execute Step S13; if the connection is successful, execute Step S6; Step S6: Obtain the interface information of the model parsed in Step S3 from the model library; Step S7: Check whether each model conforms to the connection rules, that is, whether the input and output match, according to the model connection information in Step S4 and the model interface information in Step S6; Step S8: If it does not conform to the connection rules, execute Step S13; if it conforms, execute Step S9; Step S9: Determine the execution order of each model according to the model connection information obtained in Step S4; Step S10: Generate the basic simulation program framework of the aircraft simulation system; Step S11: Add the calling code for the model initialization function to the program framework in Step S10 according to the model execution order obtained in Step S9, the model attribute information obtained in Step S4, and the model interface information obtained in Step S6; Step S12: Add the calling code for the model running function to the program framework in Step S10 according to the model execution order obtained in Step S9 and the model interface information obtained in Step S6; At this point, the automatic construction of the framework of the aircraft mathematical simulation software is completed, and a directly executable mathematical simulation software is obtained.

2. The method for automatically constructing an aircraft mathematical simulation software framework according to claim 1, characterized in that The framework structure of the aircraft mathematical simulation software further includes one or several of the engine model, seeker model, and elastic model.

3. The automatic construction method of the aircraft mathematical simulation software framework according to claim 1, characterized in that In the framework structure of the aircraft mathematical simulation software, all models are encapsulated to have a unified external representation form and are stored in the model database. The models include model input, model output, model attributes, model initialization function, and model operation function. The meanings and functions of each part are as follows: Model input: Used to receive data. The number of model inputs and the detailed information of the data types of each input are stored in the model library; Model output: Used to output data. The number of model outputs and the detailed information of the data types of each input are stored in the model library; Model attributes: Used to set the modifiable parameters inside the model; Model initialization function: Used to implement the initialization operation of the model according to the attribute settings; Model operation function: Provides an interface for the implementation of the core functions of the model.

4. The method for automatically constructing the aircraft mathematical simulation software framework according to claim 3, characterized in that In the framework structure of the aircraft mathematical simulation software, the number of servo mechanism model inputs is 3, and the data types of each input are float, float, and float respectively; the number of servo mechanism model outputs is 3, and the data types of each output are float, float, and float respectively; the attributes of the servo mechanism model are the rudder deflection angle and the limit amplitude of the rudder deflection angular velocity, and the number of attributes is 2. The data types of each attribute are float and float respectively.

5. The method for automatically constructing the aircraft mathematical simulation software framework according to any one of claims 1 to 4, characterized in that The graphical simulation process description file adopts the XML format.

6. The method for automatically constructing the aircraft mathematical simulation software framework according to any one of claims 1 to 4, characterized in that The graphical simulation process description file adopts the Json format.

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