Aircraft atmospheric altitude and radio altitude simulation method and storage medium

Abstract

The present invention belongs to the field of aircraft sensor data simulation, and relates to an aircraft atmospheric altitude and radio altitude simulation method and storage medium. The present invention generates a dynamic atmospheric altitude and radio altitude data sequence according to scene simulation parameters, and generates a data file in the time sequence of the simulation data, and obtains dynamic atmospheric altitude and radio altitude data by reading and parsing the data file, which is used for the atmospheric altitude and radio altitude simulation of the aircraft; the scene simulation parameters include time parameters, atmospheric altitude parameters, radio altitude parameters, mutation parameters, and aircraft motion parameters; the method includes a simulation scene input module, an altitude calculation module, and a file generation module when designed and implemented; the storage medium is used to store the generated atmospheric altitude and radio altitude data. The present invention provides data input for avionics equipment, and simulates atmospheric altitude and radio altitude data flexibly, conveniently, efficiently, and at low cost, solves the problem of altitude simulation of avionics equipment, and improves research and development efficiency.

Description

Technical Field

[0001] The invention belongs to the field of aircraft sensor data simulation, and relates to an aircraft atmospheric altitude and radio altitude simulation method and a storage medium. Background Art

[0002] The aircraft's atmospheric altitude and radio altitude provide aircraft altitude information during flight to help pilots navigate, control flight, and operate safely. Avionics equipment related to flight safety, such as instrument landing equipment, navigation equipment, airborne collision avoidance systems, ground proximity warning equipment, etc., need to use atmospheric altitude and / or radio altitude as data sources to realize their own functions. The sources and generation mechanisms of the two altitude data are as follows:

[0003] 1. Pressure Altitude: Pressure altitude refers to the height of an aircraft relative to the standard atmospheric pressure surface. It is usually measured by the pressure altimeter on the aircraft. The pressure altimeter determines the height of the aircraft by measuring the changes in the surrounding atmospheric pressure. It contains a pressure sensor that can sense the pressure changes in the surrounding atmosphere and convert them into altitude values. The reference of the pressure altimeter is usually the standard atmospheric pressure surface, that is, the atmospheric pressure at sea level, so the pressure altitude is the height relative to sea level;

[0004] 2. Radio Altitude: Radio altitude refers to the vertical distance between the aircraft and the ground. It is usually measured by a radio altimeter on the aircraft. The radio altimeter determines the distance between the aircraft and the ground by sending radio waves and receiving the time of their reflected signals. It contains a transmitter and a receiver. The transmitter sends radio waves and the ground echo time to calculate the height difference. The benchmark for radio altitude is usually the height of the aircraft's landing gear, that is, the minimum height from the ground.

[0005] Instrument landing equipment, navigation equipment, airborne collision avoidance systems, ground proximity warning equipment and other avionics equipment involving atmospheric altitude and / or radio altitude need to be tested and inspected in scientific research and production, testing, on-board ground testing and other links. For example, the scientific research and production process uses ARINC429 boards to simulate atmospheric altitude and radio altitude data, and avionics equipment uses the air pressure extraction method to simulate atmospheric altitude after installation. The existing technology requires hardware boards or special tools, and cannot form complex, dynamic data, and cannot form sudden changes in data. Therefore, there are various shortcomings such as high cost, low flexibility, long preparation time, and inability to achieve complex dynamic simulation. Summary of the invention

[0006] In view of the deficiencies in the prior art, the present invention provides a method and storage medium for simulating the atmospheric altitude and radio altitude of an aircraft, which solves the deficiencies in the prior art in terms of cost, flexibility, efficiency, and inability to suddenly change data, and provides low-cost, flexible and convenient dynamic data of atmospheric altitude and radio altitude. The method can meet the simulation needs of atmospheric altitude data and radio altitude data in various links of avionics equipment such as scientific research and production, experiments, and onboard ground tests.

[0007] The atmospheric altitude data and radio altitude data are automatically generated by computer programming and output as data files for use. The design and implementation of this method includes three functional modules: simulation scene input module, altitude calculation module, and file generation module.

[0008] The function of the simulation scene input module is to set and input various parameters required for the simulation scene as the basis for height calculation. The specific scene simulation parameters are shown in Table 1.

[0009] Table 1 Scenario simulation parameters

[0010] type Parameter name Aircraft motion parameters Vertical velocity, vertical acceleration, vertical jerk Time parameters Start time, end time, time resolution Atmospheric height parameters Initial value, data status Radio altitude parameters Initial value, data status, terrain height value Mutation parameters Atmospheric height mutation time, atmospheric height mutation value, radio height mutation time, radio height mutation value

[0011] The altitude calculation module receives the parameters set by the simulation scenario input module and calculates the radio altitude and atmospheric altitude values, taking into account the mutation time and value of the data.

[0012] Atmospheric altitude and radio altitude are calculated as follows:

[0013] At the mutation time of the data, the atmospheric altitude data is equal to the mutation value of the atmospheric altitude mutation time, and the radio altitude data is equal to the mutation value of the radio altitude mutation time;

[0014] At non-mutation time, the calculation formulas for atmospheric altitude data and radio altitude data are as follows:

[0015] Formula 1: Atmospheric height data = initial value of atmospheric height + vertical speed * (current time - start time) + 0.5 * vertical acceleration * (current time - start time) 2 + vertical jerk* (current time - start time) 3 / 6;

[0016] Formula 2: Radio altitude data = initial value of atmospheric altitude + vertical speed * (current time - start time) + 0.5 * vertical acceleration * (current time - start time) 2 + vertical jerk* (current time - start time) 3 / 6 + terrain height value;

[0017] The current time in Formula 1 and Formula 2 refers to the generation time of the atmospheric altitude data and the radio altitude data. The current time is between the set start time and end time, and the difference between the current time and the start time is an integer multiple of the time resolution, in seconds.

[0018] The height calculation module generates the atmospheric height data and radio height data at each specific time according to the time resolution as the input of the file generation module. When generating data, first obtain the difference between the current time and the start time, which is equal to an integer multiple of the time resolution, and then use formula 1 and formula 2 to calculate the atmospheric height data and radio height data respectively. The calculation results are the atmospheric height data sequence and radio height sequence distributed directly from the start time to the end time and separated by the time resolution.

[0019] The file generation module organizes the data to generate files. The file content includes: current time, type, altitude value, and status. The specific file format is shown in Table 2.

[0020] Table 2 Data format in the file

[0021] Data Item Data Flag illustrate Current time Toa The time when the data arrives or is generated, unit: second; Float, 4 Bytes Data Types Type 1: indicates atmospheric altitude data: 2, indicates radio altitude data: 2; char, 1 Byte Specific data value of atmospheric altitude data or radio altitude data Data Atmospheric electrical altitude data or radio altitude data, unit: feet; Float, 4 Bytes Data Status State 1: Normal; 2: Fault; 3: Non-computing; Chat, 1 Byte

[0022] The specific format of the generated data file can be, but is not limited to, the following formats: a binary file with a suffix of DAT, or a text file with a suffix of JSON.

[0023] After the data file is generated, avionics equipment using atmospheric altitude data and radio altitude data can obtain specific atmospheric altitude data and radio altitude data by reading the file to support its functional operation.

[0024] Furthermore, the specific steps of file generation are as follows:

[0025] S1: Set scene simulation parameters, including:

[0026] S11: Set time parameters: start time, end time, time resolution;

[0027] S12: Setting the atmospheric height parameter: initial value of atmospheric height;

[0028] S13: Setting radio altitude parameters: initial value of radio altitude value, terrain altitude value;

[0029] S14: Setting mutation parameters: atmospheric altitude mutation time and mutation value, radio altitude mutation time and mutation value;

[0030] S15: Set aircraft motion parameters: vertical speed, vertical acceleration, vertical jerk;

[0031] S2: Generate atmospheric altitude data and radio altitude data arranged in chronological order according to the set values ​​in S1, the specific method includes:

[0032] At the data mutation time, the atmospheric altitude data is equal to the mutation value of the atmospheric altitude mutation time, and the radio altitude data is equal to the mutation value of the radio altitude mutation time;

[0033] At non-numeric mutation time, the calculation formulas for atmospheric altitude data and radio altitude data are as shown in Formula 1 and Formula 2;

[0034] S3: Generates atmospheric altitude data and radio altitude data files.

[0035] Furthermore, the technical solution disclosed in the present invention also includes an aircraft atmospheric altitude and radio altitude storage medium, which is used to store the specific atmospheric altitude data and radio altitude data generated, and the specific contents include: current time, atmospheric altitude data and radio altitude data corresponding to the current time, data type, and data status; wherein the data types include: type 1 and type 2, type 1 indicates that the atmospheric altitude data or radio altitude data corresponding to the current time has generated a data mutation, and type 2 indicates that the atmospheric altitude data and radio altitude data corresponding to the current time have not generated a data mutation; the data status includes: normal data, fault data, and non-calculation data.

[0036] Technical effect of the present invention: Based on the method and storage medium of the present invention, the shortcomings of the current technology in terms of cost, flexibility, efficiency, and inability to generate mutation data can be solved, and a low-cost, flexible and convenient radio altitude and atmospheric altitude data dynamic simulation method is provided, which can flexibly and conveniently generate dynamic atmospheric altitude data and radio altitude data, and generate data files that are easy to carry, transmit and use. Without the need to use special hardware or equipment, the simulation needs of atmospheric altitude data and radio altitude data in various links of avionics equipment in scientific research and production, experiments, on-board ground testing, etc. can be met, thereby improving the research and development efficiency of avionics equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0038] Figure 1 The design implementation module composition block diagram of the present invention.

[0039] Figure 2 Schematic diagram of the design implementation steps of the present invention. DETAILED DESCRIPTION

[0040] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. The components of the embodiments of the present invention described and given in the drawings here can be arranged and designed in other different orders or configurations.

[0041] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0042] Example:

[0043] Figure 1 This is a block diagram of the design and implementation modules of the present invention. When the present invention is designed and implemented, it includes three functional modules: a simulation scene input module, a height calculation module, and a file generation module, and is implemented using Julia language programming.

[0044] The simulation scene input module models the aircraft motion scene through defined data variables. The definition of data variables of the simulation scene input module is shown in Table 3.

[0045] Table 3 The data variables are defined as follows:

[0046] Data Item Data Identification illustrate Vertical speed V Feet / Second Vertical acceleration a <![CDATA[feet per second 2 > Vertical jerk j <![CDATA[feet per second 3 > Start time Tstart Second End Time Tstop Second Temporal resolution T Second Initial value of atmospheric height Init_PreAlt foot Atmospheric height mutation time Tb_PreAlt Second Atmospheric height mutation value Bvalue__PreAlt foot Initial value of radio altitude Init_RadioAlt foot Radio altitude mutation time Tbst_RadioAlt Second Atmospheric height mutation value Bvalue__RadioAlt foot Terrain height GroundAlt foot Atmospheric altitude status SSM1 Normal / Faulty / Non-Computing Radio altitude status SSM2 Normal / Faulty / Non-Computing

[0047] When designing and implementing the above data definitions, a visual data interface is designed to implement data settings in the form of a dialog box.

[0048] The function of the height calculation module is to calculate the data of each time point by point from the simulation start time to the simulation end time according to the parameters set by the simulation scenario input module, in chronological order and with the time resolution as the unit; the time resolution T is the unit step of time accumulation, representing the data refresh cycle of the simulated atmospheric height data and radio height.

[0049] Figure 2 This is a schematic diagram of the design and implementation steps of the present invention. This embodiment is specifically implemented using the Julia programming language, and the method is as follows:

[0050] The first step is to generate a floating point time vector array: with T as the fixed step length, starting from time 0 and ending at Tstop-Tstart, marked as curT[];

[0051] In the second step, using formula 1, traverse each member of curT[] once to calculate the array curPretAlt[] of atmospheric height values; using formula 2, traverse each member of each curT[] once to calculate the array curRadiotAlt[] of atmospheric height values.

[0052] At this point, the calculation of atmospheric altitude data and radio altitude data is completed.

[0053] In the third step, the file generation module writes the atmospheric height value obtained in the height calculation module into the file according to the data items and data flags of the data variables defined in Table 2, thereby generating a data file. When implemented in Julia language programming, a dictionary type variable type is used to store the data defined in Table 2. The specific steps are:

[0054] Step 1: Create a structure variable of dictionary type, and the data variable defined in Table 2 is its subtype;

[0055] Step 2: Use the JSON.json() function to convert the dictionary created in step 1 into JSON string format;

[0056] Step 3: Write the JSON string to a file to generate a JSON file.

[0057] Avionics equipment such as instrument landing equipment, navigation equipment, airborne collision avoidance system, ground proximity warning equipment, etc. involving atmospheric altitude and / or radio altitude obtain dynamic atmospheric altitude and / or radio altitude data by reading and parsing the generated JSON file.

[0058] Furthermore, the JSON file is stored in a storage medium. The storage medium of this embodiment is a memory inside avionics equipment such as an instrument landing equipment, a navigation equipment, an airborne collision avoidance system, and a ground proximity warning equipment.

Claims

1. A method for simulating aircraft atmospheric altitude and radio altitude, characterized in that: According to the scene simulation parameters, dynamic atmospheric altitude data and radio altitude data are generated, and data files are generated in data time sequence. The dynamic atmospheric altitude data and radio altitude data are obtained by reading and parsing the data files, which are used for the atmospheric altitude and radio altitude simulation of the aircraft; the method described can generate data mutations: at the set atmospheric altitude mutation time, the atmospheric altitude data is equal to the set atmospheric altitude mutation value, and at the set radio altitude mutation time, the radio altitude data is equal to the set radio altitude mutation value; the method described, when designed and implemented, includes a simulation scene input module, an altitude calculation module, and a file generation module; the method described includes the following steps: S1: Set scene simulation parameters, including: S11: Set time parameters: start time, end time, time resolution; S12: Setting atmospheric height parameters: initial value of atmospheric height; S13: Setting radio altitude parameters: initial value of radio altitude, terrain altitude value; S14: Setting mutation parameters: atmospheric altitude mutation time and mutation value, radio altitude mutation time and mutation value; S15: Set aircraft motion parameters: vertical speed, vertical acceleration, vertical jerk; S2: According to the set value in S1 and in chronological order, calculate and generate the atmospheric altitude data and radio altitude data corresponding to the current time. The specific method is as follows: At the mutation time of the data, the atmospheric altitude data is equal to the mutation value of the atmospheric altitude mutation time, and the radio altitude data is equal to the mutation value of the radio altitude mutation time; At non-mutation time, the calculation formulas for atmospheric altitude data and radio altitude data are as follows: Formula 1: Atmospheric height data = atmospheric height initial value + vertical speed * (current time - start time) + 0.5 * vertical acceleration * (current time - start time) 2 + vertical jerk* (current time - start time) 3 / 6; Formula 2: Radio altitude data = initial value of atmospheric altitude + vertical speed * (current time - start time) + 0.5 * vertical acceleration * (current time - start time) 2 + vertical jerk* (current time - start time) 3 / 6+ terrain height value; The current time in Formula 1 and Formula 2 refers to the generation time of the atmospheric altitude data and the radio altitude data. The current time is between the set start time and end time, and the difference between the current time and the start time is an integer multiple of the time resolution, in seconds; S3: Generates atmospheric altitude data and radio altitude data files.

2. An aircraft atmospheric altitude and radio altitude storage medium for storing data generated by the method of claim 1, characterized in that: The contents stored in the aircraft atmospheric altitude and radio altitude storage medium include: current time, atmospheric altitude data or radio altitude data corresponding to the current time, data type, and data status; wherein the data types include: type 1 and type 2, type 1 indicates that the data corresponding to the current time is atmospheric altitude data, and type 2 indicates that the data corresponding to the current time is radio altitude data; the data status includes: normal data, fault data, and non-calculated data.

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