Flight recorder impact safety distance determination method and apparatus, and flight recorder impact safety management method and apparatus

Abstract

Disclosed in embodiments of the present description is a flight recorder impact safety distance determination method, the method comprising: establishing a digital model on the basis of flight recorder parameters, and using the digital model to perform flight recorder aerodynamic characteristic simulation, so as to obtain an air resistance model corresponding to a flight recorder; acquiring the speed and attitude of the flight recorder when the flight recorder does not eject; calculating an ejection speed increment of the flight recorder on the basis of the ejection momentum and attitude of the flight recorder; calculating an initial ejection speed of the flight recorder on the basis of the speed of the flight recorder when the flight recorder does not eject and the ejection speed increment; and on the basis of the initial ejection speed and the air resistance model, calculating an impact safety distance required for the flight recorder to reach a preset speed after ejection.

Description

Determination of impact safety distance for flight data recorders, impact safety management methods and devices Technical Field

[0001] This application relates to the field of aircraft avionics technology, and in particular to a method and device for determining the impact safety distance of a flight recorder and for impact safety management. Background Technology

[0002] The 2009 Air France AF447 and 2014 Malaysia Airlines MH370 accidents caused a global uproar, highlighting the limitations of traditional flight data recorders, such as low survival rates and difficulties in retrieval after extreme aviation accidents. In 2015, ICAO proposed the concept of a global aviation distress and safety system and began promoting the technology of Automatic Ejection Flight Recorders (ADFRs). ADFRs are critical equipment for aircraft safety and are used for accident analysis. The ADFR detaches from the aircraft during an emergency and must possess a certain level of impact resistance. Current technology verifies the impact resistance of ADFRs through strong impact tests, where the ADFR is impacted at the test impact velocity onto an impact surface; the ADFR should not be damaged after the impact.

[0003] However, even if the existing ADFR impact performance has passed the strong impact test verification, the test impact speed cannot cover all situations in which an aircraft encounters an emergency. Past aircraft accident data or accident investigations have revealed instances where the aircraft crashed at speeds exceeding the ADFR test impact speed, indicating that in reality, the actual impact speed of the ADFR may exceed its test impact speed, posing a risk of damage to the ADFR due to impact. Summary of the Invention

[0004] This specification provides a method and apparatus for determining the impact safety distance of a flight recorder and managing its impact safety, in order to solve the technical problems of how to determine the impact safety distance of a flight recorder and manage its impact safety.

[0005] To address the aforementioned technical problems, the embodiments in this specification provide the following technical solutions:

[0006] This specification provides an embodiment of a method for determining the impact safety distance of a flight recorder, the method comprising:

[0007] A digital model is established based on the parameters of the flight recorder, and the aerodynamic characteristics of the flight recorder are simulated using the digital model to obtain the air resistance model corresponding to the flight recorder.

[0008] Acquire the velocity and attitude of the flight recorder when it is not ejected; calculate the ejection velocity increment of the flight recorder based on the ejection momentum and attitude of the flight recorder; calculate the initial ejection velocity of the flight recorder based on the velocity of the flight recorder when it is not ejected and the ejection velocity increment.

[0009] Based on the initial ejection velocity and the air resistance model, calculate the impact safety distance required for the flight recorder to reach the preset velocity after ejection.

[0010] Optionally, the air resistance model includes air resistance coefficients in both the horizontal and vertical directions.

[0011] Optionally, the method further includes:

[0012] Calculate the horizontal and vertical components of the impact safety distance.

[0013] This specification provides an embodiment of a flight recorder impact safety management method, the method comprising:

[0014] A digital model is established based on the parameters of the flight recorder, and the aerodynamic characteristics of the flight recorder are simulated using the digital model to obtain the air resistance model corresponding to the flight recorder.

[0015] Determine the initial ejection velocity of the flight recorder, and calculate the impact safety distance required for the flight recorder to reach the preset velocity after ejection based on the initial ejection velocity and the air resistance model;

[0016] When a preset condition occurs, the terrain DEM data around the aircraft is acquired, and the impact safety distance is used to determine whether the impact safety conditions are met.

[0017] Optionally, determining the initial ejection velocity of the flight recorder includes:

[0018] Acquire the velocity and attitude of the flight recorder when it is not ejected; calculate the ejection velocity increment of the flight recorder based on the ejection momentum and attitude of the flight recorder; calculate the initial ejection velocity of the flight recorder based on the velocity of the flight recorder when it is not ejected and the ejection velocity increment.

[0019] Optionally, determining whether the impact safety conditions are met based on the terrain DEM data and the impact safety distance includes:

[0020] Based on the terrain DEM data, determine whether there are obstacles within the target area to determine whether the impact safety conditions are met;

[0021] The target range is determined based on the horizontal and vertical components of the impact safety distance.

[0022] Optionally, the minimum distance between the boundary of the projected area of ​​the target range in the horizontal direction and the flight recorder is not less than the horizontal component of the impact safety distance;

[0023] The minimum distance between the vertical projection area boundary of the target range and the flight recorder is not less than the vertical component of the impact safety distance.

[0024] Optionally, the method further includes:

[0025] Whether the impact safety conditions are met determines whether the flight recorder has detached from the aircraft.

[0026] This specification provides an embodiment of a flight recorder impact safety distance determination device, the device comprising:

[0027] The aerodynamic performance simulation module is used to establish a digital model based on the flight recorder parameters, use the digital model to simulate the aerodynamic characteristics of the flight recorder to obtain the air resistance model corresponding to the flight recorder, and transmit the air resistance model to the impact deceleration distance calculation module.

[0028] The initial motion state calculation module is used to determine the initial ejection velocity of the flight recorder and transmit the initial ejection velocity to the impact deceleration distance calculation module;

[0029] The impact deceleration distance real-time calculation module is used to calculate the impact safety distance required for the flight recorder to reach a preset speed after ejection, based on the initial ejection speed and the air resistance model.

[0030] This specification provides an embodiment of a flight recorder impact safety management device, the device comprising:

[0031] The aerodynamic performance simulation module is used to establish a digital model based on the flight recorder parameters, use the digital model to simulate the aerodynamic characteristics of the flight recorder to obtain the air resistance model corresponding to the flight recorder, and transmit the air resistance model to the impact deceleration distance calculation module.

[0032] An initial motion state calculation module is used to determine the initial ejection velocity of the flight recorder and transmit the initial ejection velocity to the impact deceleration distance calculation module.

[0033] The airborne data processing module is used to provide the initial motion state calculation module with the data required to determine the initial velocity of the ejection, and to provide the impact deceleration distance calculation module with the terrain DEM data around the aircraft.

[0034] The impact deceleration distance real-time calculation module is used to calculate the impact safety distance required for the flight recorder to reach the preset speed after ejection, based on the initial ejection speed and the air resistance model.

[0035] The real-time impact safety distance judgment module is used to determine whether the impact safety conditions are met based on the terrain DEM data and the impact safety distance.

[0036] The above-described at least one technical solution adopted in the embodiments of this specification can achieve the following beneficial effects:

[0037] By simulating the aerodynamic characteristics using a digital model, the air resistance model corresponding to the flight recorder can be obtained. Based on the initial ejection velocity of the flight recorder and the air resistance model, the impact safety distance of the flight recorder can be determined more accurately.

[0038] After determining the impact safety distance of the flight recorder, when a preset situation occurs, the impact safety conditions are judged based on the terrain DEM data and the impact safety distance to avoid damage to the flight recorder due to impact, thus realizing the management of the impact safety of the flight recorder. Attached Figure Description

[0039] To more clearly illustrate the technical solutions in the embodiments of this specification or the prior art, the drawings used in the description of the embodiments of this specification or the prior art will be briefly described below. Obviously, the drawings used in some embodiments of this application are only described below. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0040] Figure 1 is a flowchart illustrating the method for determining the impact safety distance of a flight recorder according to the first embodiment of this specification.

[0041] Figure 2 is a flowchart illustrating the impact safety management method for flight recorders provided in the second embodiment of this specification.

[0042] Figure 3 is a schematic diagram of the impact safety management phase of the flight recorder in the second embodiment of this specification.

[0043] Figure 4 is a structural schematic diagram of the flight recorder impact safety distance determination device provided in the third embodiment of this specification.

[0044] Figure 5 is a structural schematic diagram of the flight recorder impact safety management device provided in the fourth embodiment of this specification. Detailed Implementation

[0045] To enable those skilled in the art to better understand the technical solutions in this specification, the technical solutions in the embodiments of this specification will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments involved in the specific implementation are only a part of the embodiments of this application, and not all of the embodiments. All other embodiments obtained by those skilled in the art based on the embodiments in the specific implementation without creative effort should fall within the protection scope of this application.

[0046] The first embodiment of this specification (hereinafter referred to as "Embodiment 1") provides a method for determining the impact safety distance of a flight recorder. The executing entity of Embodiment 1 includes, but is not limited to, a terminal, a server, an operating system, or an application program; that is, the executing entity can be diverse and can be set, used, or changed as needed. Alternatively, a third-party application can assist the executing entity in performing Embodiment 1. For example, a server can execute the method provided in Embodiment 1, and a corresponding application program can be installed on a terminal (which may be held by a user). Data transmission can occur between the terminal or application program and the server, thereby assisting the server in executing the method provided in Embodiment 1.

[0047] In particular, the executing entity in Embodiment 1 can be a flight recorder or a device for controlling the flight recorder, such as an airborne device for controlling the ejection of the flight recorder.

[0048] Referring to Figure 1, the method for determining the impact safety distance of a flight recorder provided in Embodiment 1 includes:

[0049] S101: Establish a digital model based on the flight recorder parameters, and use the digital model to simulate the aerodynamic characteristics of the flight recorder in order to obtain the air resistance model corresponding to the flight recorder.

[0050] In Example 1, a digital model can be created for the flight recorder, including creating a digital model (referred to as the ADFR digital model) corresponding to the flight recorder based on its parameters. Specifically, a CAD digital model of the flight recorder can be created based on its external dimensions, weight, center of gravity, and moment of inertia.

[0051] The digital model allows for the simulation of the aerodynamic characteristics of the flight recorder, yielding an air resistance model. This air resistance model can include drag coefficients in both the horizontal and vertical directions. Specifically, the digital model can be preprocessed, and a computational domain and mesh can be defined. Simulations can then be used to derive drag in each direction, establishing an air resistance coefficient model. Finally, the corresponding drag coefficients (including both horizontal and vertical drag coefficients) can be calculated based on this model.

[0052] The aforementioned flight recorder parameters (including flight recorder system parameters) can be obtained through appropriate means, such as from the equipment manufacturer.

[0053] S103: Obtain the speed and attitude of the flight recorder when it is not ejected; calculate the ejection velocity increment of the flight recorder based on the ejection momentum and attitude of the flight recorder; calculate the initial ejection velocity of the flight recorder based on the speed of the flight recorder when it is not ejected and the ejection velocity increment.

[0054] In Example 1, the speed and attitude (including the mounting surface attitude) of the flight recorder when it is not ejected can be obtained. For example, when the flight recorder is not ejected, it is generally installed in a specific location on the aircraft (including but not limited to the airplane). Therefore, the motion parameters of the aircraft can be obtained through relevant modules of the aircraft (such as the onboard computer). The motion parameters include the aircraft attitude, which includes the mounting surface attitude. Thus, the speed and attitude of the flight recorder when it is not ejected can be determined based on the motion parameters of the aircraft. Specifically, the speed in the motion parameters of the aircraft can be used as the speed of the flight recorder when it is not ejected. The mounting surface of the flight recorder is consistent with the attitude of the aircraft skin at its installation location, so the mounting surface attitude of the flight recorder can be obtained from the aircraft attitude.

[0055] Based on the ejection momentum and attitude of the flight recorder, the ejection velocity increment can be calculated. The ejection momentum can be obtained through appropriate means, such as from the equipment manufacturer. The calculation method for the ejection velocity increment is as follows: Based on the aircraft attitude angles in the flight recorder's attitude, determine the rotation matrix for transforming the flight recorder's body coordinate system to the geocentric inertial coordinate system. Then, transform the ejection momentum of the flight recorder in the body coordinate system to the geocentric inertial coordinate system, and use the momentum equation to calculate the velocity increment caused by ejection, i.e., the ejection velocity increment.

[0056] Based on the flight recorder's speed before ejection and the increment of ejection speed, the initial ejection speed of the flight recorder can be calculated, that is, the initial speed of the flight recorder when ejection.

[0057] S105: Based on the initial ejection velocity and the air resistance model, calculate the impact safety distance required for the flight recorder to reach the preset speed after ejection.

[0058] In Example 1, the distance required for the flight recorder to reach a preset speed after ejection can be calculated based on the initial ejection velocity of the flight recorder and the aforementioned air resistance model. (Specifically, the trajectory equation of the flight recorder after separation can be obtained from kinematic formulas and Newton's second law based on the initial ejection velocity of the flight recorder and the aforementioned air resistance model, thereby calculating the distance required for the flight recorder to reach the preset speed after ejection.) This distance serves as the impact safety distance for the flight recorder. The preset speed can be set as needed; for example, the highest test impact speed without damage to the flight recorder can be used as the preset speed, meaning that the flight recorder will not be damaged if it is impacted while moving at a speed not exceeding the preset speed.

[0059] The significance of the impact safety distance lies in the fact that after the flight recorder is ejected at its initial ejection speed, its speed will decrease to the preset speed after passing through the impact safety distance. If the flight recorder is subjected to an impact while moving at a speed not exceeding the preset speed, it will not be damaged. In other words, after the flight recorder is ejected at its initial ejection speed, its speed has decreased to the preset speed or lower after passing through the impact safety distance, and the flight recorder will not be damaged under impact. Therefore, the impact safety distance can also be called the deceleration distance.

[0060] In addition to calculating the impact safety distance required for the flight recorder to reach the preset speed after ejection, the components of the impact safety distance in the horizontal and vertical directions can also be calculated, namely the horizontal component and the vertical component.

[0061] Example 1 can achieve the following beneficial effects:

[0062] Aerodynamic characteristics are simulated using a digital model to obtain the air resistance model corresponding to the flight recorder. The initial ejection velocity of the flight recorder is calculated by combining the aircraft's motion parameters. Based on the initial ejection velocity and the air resistance model, the impact safety distance of the flight recorder can be determined more accurately.

[0063] The second embodiment of this specification (hereinafter referred to as "Embodiment Two") provides a flight recorder impact safety management method. The executing entity of Embodiment Two includes, but is not limited to, a terminal, a server, an operating system, or an application program; that is, the executing entity can be diverse and can be set, used, or changed as needed. Alternatively, a third-party application can assist the executing entity in performing Embodiment Two. For example, a server can execute the method provided in Embodiment Two, and a corresponding application program can be installed on a terminal (which may be held by a user). Data transmission can occur between the terminal or application program and the server, thereby assisting the server in executing the method provided in Embodiment Two.

[0064] In particular, the executing entity in Embodiment 1 can be a flight recorder or a device for controlling the flight recorder, such as an airborne device for controlling the ejection of the flight recorder.

[0065] Referring to Figure 2, the flight recorder impact safety management method provided in Embodiment 2 includes:

[0066] S202: Establish a digital model based on the flight recorder parameters, and use the digital model to simulate the aerodynamic characteristics of the flight recorder in order to obtain the air resistance model corresponding to the flight recorder.

[0067] For specific implementation details, please refer to S101.

[0068] S204: Determine the initial ejection velocity of the flight recorder, and calculate the impact safety distance required for the flight recorder to reach the preset velocity after ejection based on the initial ejection velocity and the air resistance model;

[0069] In Example 2, the initial ejection velocity of the flight recorder can be determined. Determining the initial ejection velocity of the flight recorder may include: acquiring the velocity and attitude of the flight recorder before ejection; calculating the ejection velocity increment of the flight recorder based on the ejection momentum and attitude; and calculating the initial ejection velocity of the flight recorder based on the velocity of the flight recorder before ejection and the ejection velocity increment. For details on how to determine or calculate the initial ejection velocity of the flight recorder, please refer to S103.

[0070] Based on the initial ejection velocity of the flight recorder and the aforementioned air resistance model, the distance required for the flight recorder to reach a preset speed after ejection can be calculated. This distance serves as the impact safety distance for the flight recorder. Specific implementation can be found in S105.

[0071] S206: When a preset condition occurs, acquire the terrain DEM data around the aircraft, and determine whether the impact safety conditions are met based on the terrain DEM data and the impact safety distance.

[0072] In Embodiment 2, preset conditions can be pre-set. When a preset condition occurs, terrain DEM data around the aircraft is acquired. For example, an aircraft encountering distress or a specific situation can be used as a preset condition. Generally, a preset condition requires the flight recorder to detach from the aircraft; the specific content of the preset condition is not limited in Embodiment 2. The executing entity in Embodiment 2 can be connected to relevant aircraft equipment and determine whether a preset condition has occurred based on information from the relevant aircraft equipment.

[0073] When a preset condition is met, the current position of the aircraft can be obtained, and then the terrain DEM data of the area surrounding the aircraft (specifically, a certain range around the aircraft) can be acquired. For example, the terrain DEM data can be collected by the corresponding devices of the aircraft, so the terrain DEM data can be obtained through the relevant modules of the aircraft (such as the onboard computer).

[0074] In Example 2, the impact safety conditions can be determined based on the terrain DEM data and the impact safety distance of the flight recorder. Specifically, determining whether the impact safety conditions are met based on the terrain DEM data and the impact safety distance of the flight recorder can include: determining whether there are obstacles (including but not limited to ground or mountains) within the target area based on the terrain DEM data to determine whether the impact safety conditions are met; wherein, the target area is determined based on the horizontal and vertical components of the impact safety distance. For example, if the terrain DEM data determines that there are no obstacles within the target area, then the impact safety conditions are met; if the terrain DEM data determines that there are obstacles within the target area, then the impact safety conditions are not met.

[0075] Preferably, the minimum distance between the horizontal projection area boundary of the target range and the flight recorder is not less than the horizontal component of the impact safety distance; the minimum distance between the vertical projection area boundary of the target range and the flight recorder is not less than the vertical component of the impact safety distance. The target range is a cylinder, with the projection of its base circle onto the horizontal plane centered on the flight recorder position and having the horizontal component of the impact safety distance as its radius; the height of the target range is twice the vertical component of the impact safety distance, and the midpoint of the height of the target range is the flight recorder position.

[0076] Of course, when the preset situation occurs, the flight recorder is generally still moving with the aircraft. Therefore, the above target range is not a fixed spatial range, but a spatial range that surrounds the flight recorder and moves with the flight recorder.

[0077] After defining the target area according to the above requirements, when the flight recorder detaches from the aircraft via ejection or other means, it will not be damaged by impacts from obstacles within the target area. When the flight recorder reaches the boundary of the target area, the distance traveled by the flight recorder will not be less than the impact safety distance, and the speed of the flight recorder will not exceed the aforementioned preset speed. Even if the flight recorder subsequently encounters another impact (such as hitting the ground, falling into water, or reaching the impact point), it will not be damaged. In other words, under the condition of meeting the impact safety requirements, the flight recorder will not be damaged by impacts after detaching from the aircraft, whether within or beyond the target area.

[0078] As mentioned above, after a preset condition occurs, the aircraft is generally still in motion, thus allowing for continuous acquisition of terrain DEM data around the aircraft to continuously determine whether the impact safety conditions are met. Based on whether the impact safety conditions are met, it is determined whether the flight recorder should detach from the aircraft. Specifically, if the impact safety conditions are met, the flight recorder is detached from the aircraft using an appropriate method such as ejection; if the impact safety conditions are not yet met, the process can wait until they are met before detaching the flight recorder using an appropriate method such as ejection. For example, if the impact safety conditions are met at a certain moment, it means that there are no obstacles within the target area at that time, and the flight recorder will not encounter obstacle impacts from detaching from the aircraft until reaching the boundary of the target area, then the flight recorder can be detached from the aircraft.

[0079] The application of Embodiment 1 and Embodiment 2 will be illustrated below with reference to Figure 3:

[0080] This example illustrates the ADFR installation phase, the normal flight phase, and the distress phase.

[0081] a) ADFR installation phase: Obtain ADFR parameters (i.e. system parameters), establish an ADFR digital model based on the ADFR parameters; use the ADFR digital model to perform ADFR aerodynamic characteristic simulation to obtain the ADFR air resistance model, which includes air resistance coefficients in the horizontal and vertical directions.

[0082] b) Normal flight phase: Acquire aircraft motion parameters, including the real-time attitude and velocity of the ADFR mounting surface, i.e., the attitude and velocity of the ADFR before ejection. Calculate the ADFR velocity increment resulting from ejection based on the ADFR ejection momentum and ADFR attitude. Calculate the ADFR initial ejection velocity in real-time by combining the ADFR's velocity before ejection and the velocity increment resulting from ejection. Based on the ADFR initial ejection velocity and its air resistance model, calculate in real-time the distance required for deceleration to the preset velocity after ejection (i.e., the impact safety distance), as well as the horizontal and vertical components of this distance.

[0083] Distress Phase: When an aircraft encounters a distress situation (a pre-set condition), an ADFR (Advanced Deployment Response) ejection signal is generated. Real-time acquisition of the aircraft's current position and nearby terrain DEM (Digital Elevation Model) data is used. Based on the terrain DEM data, the system continuously assesses whether there are obstacles within the horizontal and vertical components of the impact safety distance centered on the aircraft's flight recorder (within the target area) (i.e., performing hazard analysis in both horizontal and vertical directions). If there are no obstacles, it means the current distance between the ADFR and the impact position is not less than the impact safety distance, meeting the impact safety conditions, and the ADFR can be ejected from the aircraft.

[0084] Example 2 can achieve the following beneficial effects:

[0085] After determining the impact safety distance for the flight recorder, when a preset situation occurs, the system uses terrain elevation data near the aircraft and the aforementioned impact safety distance to determine in real time whether the impact safety conditions are met, and whether ejection of the flight recorder is safe at that moment. If the impact safety conditions are met, the flight recorder detaches from the aircraft and will not be damaged by the impact. This achieves control over the timing of flight recorder ejection and management of impact safety, maximizing flight recorder safety and preventing damage due to impact speed exceeding the preset speed after ejection, thus increasing the flight recorder's survival probability.

[0086] Furthermore, the study considered the impact of aircraft operating conditions on the initial ejection velocity of the flight recorder, as well as the influence of the actual distance between the flight recorder and the potential impact surface on the deceleration effect. For example, it considered whether there were potential impact surfaces (including potential obstacles) within the target area, whether the distance between the flight recorder and the potential impact surface met the impact safety distance, and whether the flight recorder could decelerate to the preset speed before encountering the potential impact surface. By comprehensively considering these factors to determine whether the impact safety conditions are met, and thus controlling the ejection timing of the flight recorder, the study can more accurately determine whether the flight recorder can eject and more effectively manage the impact safety of the flight recorder.

[0087] In particular, since the flight recorder does not have to be detached from the aircraft after a preset condition occurs, but only after the impact safety conditions are met, the flight recorder can save and record as much flight data as possible before detaching from the aircraft, which is conducive to maximizing the function of the flight recorder.

[0088] The third embodiment of this specification provides a flight recorder impact safety distance determination device corresponding to the method described in Embodiment 1, which can be used to execute the method described in Embodiment 1.

[0089] Referring to Figure 4, the apparatus provided in the third embodiment includes:

[0090] The aerodynamic performance simulation module is used to establish a digital model based on the flight recorder parameters, use the digital model to simulate the aerodynamic characteristics of the flight recorder to obtain the air resistance model corresponding to the flight recorder, and transmit the air resistance model to the impact deceleration distance calculation module.

[0091] An initial motion state calculation module is used to determine the initial ejection velocity of the flight recorder and transmit the initial ejection velocity to the impact deceleration distance calculation module.

[0092] The impact deceleration distance real-time calculation module is used to calculate the impact safety distance required for the flight recorder to reach a preset speed after ejection, based on the initial ejection speed and the air resistance model.

[0093] The modules of the third embodiment will be further explained below:

[0094] (1) Aerodynamic performance simulation module (or ADFR aerodynamic performance simulation module)

[0095] Based on the ADFR parameters (which can be provided by the ADFR equipment manufacturer), an ADFR digital model is established. The air drag coefficients in the horizontal and vertical directions are obtained through characteristic simulation, and an air drag model (or aerodynamic model) is constructed. The ADFR air drag model is then transferred to the impact deceleration distance calculation module.

[0096] (2) Initial motion state calculation module (or ADFR initial motion state calculation module)

[0097] Based on the velocity increment caused by the ejection to the ADFR (which can be provided by the ADFR equipment manufacturer), and the aircraft's attitude and velocity at the current moment, the initial ejection velocity of the ADFR is calculated and transmitted to the impact deceleration distance calculation module.

[0098] (3) Real-time calculation module for impact deceleration distance

[0099] Based on the ADFR air resistance model and the real-time calculated ADFR ejection initial velocity, the kinematic equations of ADFR after ejection separation are established, and the distance required for ADFR to decelerate to the preset speed (i.e., the impact safety distance) and the components of this distance in the horizontal and vertical directions are calculated.

[0100] The modules in the third embodiment can be connected in a suitable manner. For the contents not described in detail in the third embodiment, please refer to the first embodiment. The third embodiment can achieve the same beneficial effects as the first embodiment.

[0101] The fourth embodiment of this specification provides a flight recorder impact safety management device corresponding to the method described in Embodiment 2, which can be used to execute the method described in Embodiment 2.

[0102] Referring to Figure 5, the apparatus provided in the fourth embodiment includes:

[0103] The aerodynamic performance simulation module is used to establish a digital model based on the flight recorder parameters, use the digital model to simulate the aerodynamic characteristics of the flight recorder to obtain the air resistance model corresponding to the flight recorder, and transmit the air resistance model to the impact deceleration distance calculation module.

[0104] An initial motion state calculation module is used to determine the initial ejection velocity of the flight recorder and transmit the initial ejection velocity to the impact deceleration distance calculation module.

[0105] The airborne data processing module is used to provide the initial motion state calculation module with the data required to determine the initial velocity of the ejection, and to provide the impact deceleration distance calculation module with the terrain DEM data around the aircraft.

[0106] The impact deceleration distance real-time calculation module is used to calculate the impact safety distance required for the flight recorder to reach the preset speed after ejection, based on the initial ejection speed and the air resistance model.

[0107] The real-time impact safety distance judgment module is used to determine whether the impact safety conditions are met based on the terrain DEM data and the impact safety distance.

[0108] The modules of the fourth embodiment will be further explained below:

[0109] (1) Aerodynamic performance simulation module (or ADFR aerodynamic performance simulation module)

[0110] Based on the ADFR parameters (which can be provided by the ADFR equipment manufacturer), an ADFR digital model is established. The air drag coefficients in the horizontal and vertical directions of the ADFR are obtained through aerodynamic characteristic simulation, and an air drag model (or aerodynamic model) is constructed. The ADFR air drag model is then transferred to the impact deceleration distance calculation module.

[0111] (2) Initial motion state calculation module (or ADFR initial motion state calculation module)

[0112] Based on the velocity increment caused by the ejection to the ADFR (which can be provided by the ADFR equipment manufacturer) and the current aircraft attitude and velocity provided by the onboard data processing module, the initial ejection velocity of the ADFR is calculated and transmitted to the impact deceleration distance calculation module.

[0113] (3) Airborne data processing module

[0114] The system acquires digital elevation model (DEM) data of the aircraft's attitude and speed, as well as the terrain around the aircraft, from the aircraft. It provides the necessary information, such as aircraft attitude and speed information, to the ADFR initial motion state calculation module, and provides the DEM data of the terrain around the aircraft to the impact safety distance judgment module.

[0115] (4) Real-time calculation module for impact deceleration distance

[0116] Based on the ADFR air resistance model and the real-time calculated ADFR ejection initial velocity, the kinematic equations of ADFR after ejection separation are established, and the distance required for ADFR to decelerate to the preset speed (i.e., the impact safety distance) and the components of this distance in the horizontal and vertical directions are calculated.

[0117] (5) Real-time impact safety distance judgment module

[0118] Based on the DEM data of the terrain near the aircraft, the system can determine in real time whether there are any obstacles within the horizontal and vertical components of the distance required to decelerate to the preset speed, in order to determine whether the impact will cause damage to the ADFR.

[0119] The application of the third and fourth embodiments will be illustrated below with reference to Figure 3:

[0120] This example illustrates the ADFR installation phase, the normal flight phase, and the distress phase.

[0121] a) ADFR installation phase: Obtain ADFR parameters (i.e. system parameters), establish an ADFR digital model based on the ADFR parameters; use the ADFR digital model to perform ADFR aerodynamic characteristic simulation to obtain the ADFR air resistance model, which includes air resistance coefficients in the horizontal and vertical directions.

[0122] b) Normal flight phase: Aircraft motion parameters are acquired from the onboard data processing module, and the attitude and velocity of the ADFR mounting surface are obtained in real time, i.e., the attitude and velocity of the ADFR before ejection. Based on the ADFR ejection momentum and ADFR attitude, the velocity increment of the ADFR caused by ejection is calculated. The initial ejection velocity of the ADFR is calculated in real time by combining the speed of the ADFR before ejection and the velocity increment caused by ejection; based on the initial ejection velocity of the ADFR and its air resistance model, the distance required for it to decelerate to the preset speed after ejection (i.e., the impact safety distance), as well as the horizontal and vertical components of this distance, are calculated in real time.

[0123] Distress Phase: When an aircraft encounters a distress situation (a pre-set condition), an ADFR (Advanced Deployment Response) ejection signal is generated. The onboard data processing module acquires real-time data on the aircraft's current position and the surrounding terrain (DEM) data. Based on this terrain DEM data, it determines in real-time whether there are any obstacles within the horizontal and vertical components of the impact safety distance centered on the aircraft's flight recorder (the target area) (i.e., performs hazard analysis in both horizontal and vertical directions). If there are no obstacles, it means the current distance between the ADFR and the impact location is not less than the impact safety distance, meeting the impact safety conditions, and the ADFR can be ejected from the aircraft.

[0124] The modules in the fourth embodiment can be connected in a suitable manner. For the contents not described in detail in the fourth embodiment, refer to the second embodiment. The fourth embodiment can achieve the same beneficial effects as the second embodiment.

[0125] The above description is merely an embodiment of this specification and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principle of this application should be included within the scope of the claims of this application.

Claims

1. A method for determining the impact safety distance of a flight recorder, characterized in that, The method includes: A digital model is established based on the parameters of the flight recorder, and the aerodynamic characteristics of the flight recorder are simulated using the digital model to obtain the air resistance model corresponding to the flight recorder. Acquire the velocity and attitude of the flight recorder when it is not ejected; calculate the ejection velocity increment of the flight recorder based on the ejection momentum and attitude of the flight recorder; calculate the initial ejection velocity of the flight recorder based on the velocity of the flight recorder when it is not ejected and the ejection velocity increment. Based on the initial ejection velocity and the air resistance model, calculate the impact safety distance required for the flight recorder to reach the preset velocity after ejection.

2. The method as described in claim 1, characterized in that, The air resistance model includes air resistance coefficients in both the horizontal and vertical directions.

3. The method as described in claim 1, characterized in that, The method further includes: Calculate the horizontal and vertical components of the impact safety distance.

4. A method for managing the impact safety of flight recorders, characterized in that, The method includes: A digital model is established based on the parameters of the flight recorder, and the aerodynamic characteristics of the flight recorder are simulated using the digital model to obtain the air resistance model corresponding to the flight recorder. Determine the initial ejection velocity of the flight recorder, and calculate the impact safety distance required for the flight recorder to reach the preset velocity after ejection based on the initial ejection velocity and the air resistance model; When a preset condition occurs, the terrain DEM data around the aircraft is acquired, and the impact safety distance is used to determine whether the impact safety conditions are met.

5. The method as described in claim 4, characterized in that, Determining the initial ejection velocity of the flight recorder includes: Acquire the velocity and attitude of the flight recorder when it is not ejected; calculate the ejection velocity increment of the flight recorder based on the ejection momentum and attitude of the flight recorder; calculate the initial ejection velocity of the flight recorder based on the velocity of the flight recorder when it is not ejected and the ejection velocity increment.

6. The method as described in claim 4, characterized in that, Determining whether the impact safety conditions are met based on the terrain DEM data and the impact safety distance includes: Based on the terrain DEM data, determine whether there are obstacles within the target area to determine whether the impact safety conditions are met; The target range is determined based on the horizontal and vertical components of the impact safety distance.

7. The method as described in claim 6, characterized in that, The minimum distance between the horizontal projection area boundary of the target range and the flight recorder is not less than the horizontal component of the impact safety distance. The minimum distance between the vertical projection area boundary of the target range and the flight recorder is not less than the vertical component of the impact safety distance.

8. The method as described in claim 4, characterized in that, The method further includes: Whether the impact safety conditions are met determines whether the flight recorder has detached from the aircraft.

9. A device for determining the impact safety distance of a flight recorder, characterized in that, The device includes: The aerodynamic performance simulation module is used to establish a digital model based on the flight recorder parameters, use the digital model to simulate the aerodynamic characteristics of the flight recorder to obtain the air resistance model corresponding to the flight recorder, and transmit the air resistance model to the impact deceleration distance calculation module. An initial motion state calculation module is used to determine the initial ejection velocity of the flight recorder and transmit the initial ejection velocity to the impact deceleration distance calculation module. The impact deceleration distance calculation module is used to calculate the impact safety distance required for the flight recorder to reach a preset speed after ejection, based on the initial ejection speed and the air resistance model.

10. A flight recorder impact safety management device, characterized in that, The device includes: The aerodynamic performance simulation module is used to establish a digital model based on the flight recorder parameters, use the digital model to simulate the aerodynamic characteristics of the flight recorder to obtain the air resistance model corresponding to the flight recorder, and transmit the air resistance model to the impact deceleration distance calculation module. An initial motion state calculation module is used to determine the initial ejection velocity of the flight recorder and transmit the initial ejection velocity to the impact deceleration distance calculation module. The airborne data processing module is used to provide the initial motion state calculation module with the data required to determine the initial velocity of the ejection, and to provide the impact deceleration distance calculation module with the terrain DEM data around the aircraft. The impact deceleration distance real-time calculation module is used to calculate the impact safety distance required for the flight recorder to reach the preset speed after ejection, based on the initial ejection speed and the air resistance model. The real-time impact safety distance judgment module is used to determine whether the impact safety conditions are met based on the terrain DEM data and the impact safety distance.

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