A design and verification method for separating different environments of a manned spacecraft escape tower

Abstract

This invention discloses a method for designing and verifying the separation of an escape tower for manned spacecraft under different environments, including: determining the initial values ​​of the escape separation dynamics; obtaining the technical requirements for a solid rocket motor based on the initial values ​​of the escape separation dynamics; obtaining the solid rocket motor based on the technical requirements of the solid rocket motor; conducting tests on the solid rocket motor to obtain the internal ballistic curve of the motor; obtaining the normal separation trajectory and the escape separation trajectory; performing near-field structural interference analysis based on the normal separation trajectory and the escape separation trajectory to obtain a conclusion on whether there is near-field interference collision; performing far-field collision risk analysis based on the normal separation trajectory and the escape separation trajectory to obtain a conclusion on whether there is far-field interference collision; and determining the success of the escape separation design based on the conclusions on whether there is near-field interference collision and whether there is far-field interference collision. This invention ensures flight safety.

Description

Technical Field

[0001] This invention belongs to the field of escape tower separation technology for manned spacecraft, and particularly relates to a design and verification method for the separation of escape towers for manned spacecraft in different environments. Background Technology

[0002] Manned spacecraft typically employ an escape tower + whole-spacecraft escape scheme. Escape within the atmosphere is achieved using the escape tower, while outside the atmosphere, after normal tower jettisoning, the entire spacecraft escapes. Launch missions are categorized into normal flight missions and emergency escape missions, both of which include the escape tower separation process. In each phase of a normal flight mission, the escape tower separates from the spacecraft after the fairing separates outside the atmosphere. In emergency escape missions within the atmosphere, during emergency flight conditions, the escape tower and spacecraft form a tower-return assembly (also known as an escape vehicle) and fly a certain distance before the escape tower separates. Therefore, escape tower separation is a necessary step in the launch process of a manned spacecraft.

[0003] To ensure flight safety, the escape tower must separate normally and without colliding with the spacecraft or launch vehicle after separation, especially during atmospheric separation where the escape tower and reentry capsule are subject to suction resistance. Therefore, the design of the escape tower separation scheme and its safety are crucial steps in the development of manned spacecraft.

[0004] The separation safety assessment of escape towers presents significant challenges due to varying external environments across different mission types (near-Earth missions, lunar missions) and flight profiles (occurring at altitudes beyond the Karman line during normal flight, and potentially both inside and outside the atmosphere during escape flight). Analysis of severe operating conditions is crucial to ensure the safety of the separation scheme design. This assessment should cover near-field structural interference and far-field collision safety. Near-field safety refers to the absence of structural interference or engine jet damage between the escape tower and the return capsule within seconds of separation. Far-field safety refers to the absence of collisions between the escape tower and the return capsule's trajectory after a certain separation time with the launch vehicle. The existing design and verification capabilities for escape tower separation in different environments for manned spacecraft urgently need refinement and improvement based on these requirements. Summary of the Invention

[0005] The technical problem solved by this invention is to overcome the shortcomings of the prior art and provide a design and verification method for the separation of escape towers for manned spacecraft in different environments, thereby ensuring flight safety.

[0006] The objective of this invention is achieved through the following technical solution: a method for designing and verifying the separation of a manned spacecraft escape tower under different environments, comprising: determining the initial value of the escape separation dynamics; obtaining the solid rocket motor technical requirements based on the initial value of the escape separation dynamics; obtaining the solid rocket motor based on the solid rocket motor technical requirements; conducting experiments on the solid rocket motor to obtain the internal ballistic curve of the motor; performing separation dynamics simulation under normal flight conditions based on the mass characteristics in the solid rocket motor technical requirements and the internal ballistic curve of the motor to obtain the normal separation trajectory; performing separation dynamics simulation under escape flight conditions based on the mass characteristics in the solid rocket motor technical requirements and the internal ballistic curve of the motor to obtain the escape separation trajectory; performing near-field structural interference analysis based on the normal separation trajectory and the escape separation trajectory to obtain a conclusion on whether there is near-field interference collision; performing far-field collision risk analysis based on the normal separation trajectory and the escape separation trajectory to obtain a conclusion on whether there is far-field interference collision; and determining the success of the escape separation design based on the conclusions on whether there is near-field interference collision and whether there is far-field interference collision.

[0007] In the above-mentioned design and verification methods for the separation of escape towers in different environments for manned spacecraft, determining the initial dynamic values ​​for escape separation includes: determining the specific process of escape tower separation; establishing a dynamic simulation model of escape tower separation based on the specific process of escape tower separation; and obtaining the initial dynamic values ​​for escape separation based on the dynamic simulation model of escape tower separation.

[0008] In the above-mentioned design and verification methods for the separation of the escape tower in different environments of manned spacecraft, the specific process of the escape tower separation includes three stages: a) from the start of the separation between the escape tower and the return capsule to the maximum longitudinal distance between the escape tower and the return capsule; b) from the maximum longitudinal distance between the escape tower and the return capsule to the point where the escape tower is overtaken by the spacecraft from a longitudinal perspective; c) from the point where the escape tower is overtaken by the spacecraft from a longitudinal perspective to the point where the escape tower moves to the tail of the rocket, thus completing the safe separation from the spacecraft.

[0009] The above-mentioned design and verification methods for the separation of escape towers in different environments for manned spacecraft include establishing a dynamic simulation model of escape tower separation, which includes: defining the coordinate system required for modeling; obtaining the input conditions for the simulation model; using the mathematical calculation software Matlab to establish a dynamic numerical simulation model of the escape tower separation process within the atmosphere; and using the multibody dynamics software Adams to establish a dynamic numerical simulation model of the escape tower separation process outside the atmosphere.

[0010] In the above-mentioned escape tower separation design and verification methods for manned spacecraft under different environments, the initial values ​​of escape separation dynamics include axial escape separation thrust parameters and lateral escape separation thrust parameters.

[0011] The above-mentioned design and verification methods for the separation of escape towers in different environments for manned spacecraft yield the following technical requirements for solid rocket motors: determining the mission function of the escape separation motor; determining the environmental conditions that the escape separation motor needs to face; determining the operating mode of the escape separation motor; and determining the performance requirements of the escape separation motor.

[0012] In the aforementioned design and verification methods for the separation of escape towers in different environments for manned spacecraft, the mission functions of the escape separation engine include: providing thrust for separation; being able to independently perform separation missions between the escape tower and the return capsule both inside and outside the atmosphere; having the ability to simultaneously ignite the escape tower integrated service unit and the return capsule shoulder integrated service unit; and having the ability to measure engine combustion chamber pressure and transmit data. The environmental conditions that the escape separation engine needs to face include: natural environment, assembly and testing environment, and spacecraft environment. The operating modes of the escape separation engine include: normal flight mission separation and escape flight mission separation. The performance requirements of the escape separation engine include: thrust magnitude, operating time, engine mass, ambient temperature, atmospheric pressure, electromagnetic compatibility requirements, and mechanical and thermal conditions.

[0013] In the above-mentioned design and verification method for the separation of escape towers in different environments of manned spacecraft, obtaining the normal separation trajectory includes the following steps: (a1) giving simulation input conditions; (b1) simulation analysis considering deviation factors; (c1) using numerical integration method to perform dynamic simulation and obtain the relative displacement curve and attitude curve of the escape tower and the rocket; (d1) judging whether there is collision interference in the near field and far field based on the relative displacement curve and attitude curve of the escape tower and the rocket; (e1) repeating steps (a1) to (d1) using the preset escape main engine thrust curve; (f1) considering the failure case of non-ignition, which is the escape tower sliding condition without power, setting the escape tower separation power to 0, and repeating steps (a1) to (d1).

[0014] In the above-mentioned design and verification methods for the separation of escape towers under different environments for manned spacecraft, obtaining the escape separation trajectory includes the following steps: (a2) giving simulation input conditions; (b2) since the escape tower separation occurs within the atmosphere under the escape flight condition, the influence of aerodynamic forces cannot be ignored. The aerodynamic forces, aerodynamic torques, and interstage suction when the return capsule separates from the escape tower need to be considered in the escape tower separation dynamic simulation model; (c2) the simulation analysis should consider deviation factors; (d2) use the numerical integration method to perform dynamic simulation and obtain the relative displacement curve and attitude curve of the escape tower and the spacecraft; (e2) consider the escape tower sliding condition without power, assume that the escape tower return capsule has no physical connection, set the escape tower separation power to 0, and repeat steps (a2) to (d2).

[0015] In the aforementioned design and verification methods for the separation of escape towers in different environments for manned spacecraft, the near-field structural interference analysis includes: calculating the time-varying curve of the minimum distance L between the escape tower and the return capsule geometry based on the preset relative distance variation curve and the preset spacecraft attitude curve. If L is always positive, no structural interference will occur; if L has a negative value, structural interference will occur. To ensure near-field safety during separation, a safety distance tolerance L0 is set. If the minimum distance between the escape tower and the return capsule geometry is L0, then... min If the distance is greater than L0, the near-field separation is considered safe. The far-field collision risk analysis includes: if the relative distance between the escape tower and the return capsule gets closer and closer over time, there is a collision risk; if the relative distance between the escape tower and the return capsule first decreases and then increases over time, the minimum relative distance between the escape tower and the return capsule is used as the evaluation point. If the minimum relative distance is greater than the set value, there is no collision risk; otherwise, there is a risk. If the relative distance between the escape tower and the return capsule continuously increases over time, there is no risk of far-field collision during separation.

[0016] Compared with the prior art, the present invention has the following advantages:

[0017] (1) This invention solves the problem of escape tower separation design that urgently needs to be solved for manned spacecraft;

[0018] (2) The escape tower separation design method proposed in this invention can adapt to the escape tower separation requirements of normal flight conditions and emergency escape conditions, and realize the safe separation of the escape tower from the spacecraft under different severe stress conditions of near-Earth / lunar mission coordination, normal flight and escape flight. Attached Figure Description

[0019] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0020] Figure 1 This is a flowchart of the design and verification method for the separation of a manned spacecraft escape tower under different environments provided in the embodiments of the present invention;

[0021] Figure 2(a) is a schematic diagram of the initial separation moment between the escape tower and the manned spacecraft return capsule provided in an embodiment of the present invention;

[0022] Figure 2(b) is a schematic diagram of stage I of the three stages of separation between the escape tower and the manned spacecraft return capsule provided in the embodiment of the present invention;

[0023] Figure 2(c) is a schematic diagram of stage II of the three stages of the separation between the escape tower and the manned spacecraft return capsule provided in the embodiment of the present invention;

[0024] Figure 2(d) is a schematic diagram of stage III of the three stages of the separation between the escape tower and the manned spacecraft return capsule provided in the embodiment of the present invention;

[0025] Figure 3 This is a schematic diagram of the dynamic model provided in an embodiment of the present invention;

[0026] Figure 4 This is a schematic diagram of the sea-level thrust curve of the escape tower separation engine provided in an embodiment of the present invention;

[0027] Figure 5 This is a schematic diagram of the near-field separation process of the escape tower provided in an embodiment of the present invention. Detailed Implementation

[0028] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the disclosure to those skilled in the art. It should be noted that, unless otherwise specified, the embodiments and features described herein can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0029] To ensure flight safety, the escape tower must separate normally and without colliding with the spacecraft or launch vehicle after separation, especially during atmospheric separation where the escape tower and reentry capsule are subject to suction resistance. Therefore, the design of the escape tower separation scheme and its safety are crucial steps in the development of manned spacecraft.

[0030] The separation safety assessment needs to address the significant differences in external environments during escape tower separation, which occurs in different mission types (near-Earth missions, lunar missions) and flight profiles (occurring at altitudes beyond the Karman line during normal flight, and potentially both inside and outside the atmosphere during escape flight). Analysis should be conducted for severe conditions (such as short intervals between escape tower separation and parachute deployment at zero altitude, severe aerodynamic conditions at maximum dynamic pressure making the escape tower prone to tipping, and deviations in thrust between vacuum separation and ground conditions) to ensure the feasibility and safety of the separation scheme design. This assessment should also cover near-field structural interference and far-field collision safety. Near-field safety refers to the absence of structural interference or engine jet damage between the escape tower and the return capsule within seconds of separation, while far-field safety refers to the absence of collisions between the escape tower's trajectory and the launch vehicle or the return capsule's individual compartments after a certain separation time.

[0031] Figure 1 This is a flowchart illustrating the design and verification method for separating a manned spacecraft escape tower under different environments, as provided in this embodiment of the invention. Figure 1 As shown, the method includes the following steps:

[0032] Determine the initial values ​​of the escape separation dynamics;

[0033] Based on the initial value of the escape separation kinetic energy, the technical requirements of the solid rocket motor are obtained. Based on the technical requirements of the solid rocket motor, the solid rocket motor is obtained. The internal ballistic curve of the solid rocket motor is obtained by conducting tests.

[0034] Based on the mass characteristics and internal ballistic curves of the solid rocket motor technical requirements, separation dynamics simulation under normal flight conditions is carried out to obtain the normal separation trajectory.

[0035] Based on the mass characteristics and internal ballistic curves of the solid rocket motor technical requirements, separation dynamics simulation under escape flight conditions is carried out to obtain the escape separation trajectory.

[0036] Based on the normal separation trajectory and the escape separation trajectory, perform near-field structural interference analysis to obtain a conclusion on whether there is near-field interference collision;

[0037] Based on the normal separation trajectory and the escape separation trajectory, a separation far-field collision risk analysis is conducted to obtain a conclusion on whether there is a far-field interference collision.

[0038] The success of the escape separation design can be judged based on the conclusions regarding whether near-field and far-field interference collisions occur.

[0039] Specifically, the design steps of the separation scheme in this embodiment are as follows:

[0040] Step 1: Determine the initial values ​​of the escape separation dynamics

[0041] Step 1.1 Determine the escape tower separation scheme and the specific separation process, which includes three stages: a) from the start of separation between the escape tower and the return capsule to the point where the escape tower and the return capsule are separated to their maximum longitudinal distance; b) from the point where the escape tower and the return capsule are separated to their maximum longitudinal distance to the point where the escape tower is overtaken by the spacecraft from a longitudinal perspective; c) from the point where the escape tower is overtaken by the spacecraft from a longitudinal perspective to the point where the escape tower moves to the tail of the rocket, thus completing the safe separation from the spacecraft.

[0042] Step 1.2 Based on the escape tower separation scheme and specific separation process in Step 1.1, establish an escape tower separation dynamic simulation model; wherein, the escape tower separation dynamic simulation model includes a) defining the coordinate system required for modeling; b) obtaining the input conditions of the simulation model; c) using the mathematical calculation software Matlab to establish a dynamic numerical simulation model of the escape tower separation process within the atmosphere; d) using the multibody dynamics software Adams to establish a dynamic numerical simulation model of the escape tower separation process outside the atmosphere.

[0043] Step 1.3 Based on the escape tower separation dynamics simulation model in Step 1.2, determine the axial and lateral escape separation thrust parameters, which are the initial values ​​of the escape separation dynamics.

[0044] Step Two: Detailed Engine Design and Internal Ballistic Prediction

[0045] Step 2.1 Based on the initial escape separation power value in Step 1.3, and combined with the solid rocket motor principle, analyze the performance characteristics of the solid rocket motor and give technical requirements, including: determining the mission function of the escape separation motor, determining the environmental conditions that the escape separation motor needs to face, determining the working mode of the escape separation motor, and determining the performance requirements of the escape separation motor.

[0046] Step 2.2 Based on the solid rocket motor technical requirements given in Step 2.1, carry out the specific design of the solid rocket motor, including: a) determining the specific scheme of each part of the separation motor according to the escape separation motor technical requirements; b) obtaining the propellant shape to provide structural state parameters for the subsequent internal trajectory of the propulsion system;

[0047] Step 2.3 Based on the design results of Step 2.2, obtain the internal ballistic curve of the engine through experiments;

[0048] Step 3: Ballistic Separation Simulation

[0049] Step 3.1 Based on the engine mass characteristics designed in Step 2.2 and the internal ballistic curve designed in Step 2.3, conduct separation dynamics simulation under normal flight conditions to obtain the normal separation trajectory. This step includes: a) giving simulation input conditions; b) simulation analysis considering deviation factors; c) using numerical integration method to perform dynamics simulation and obtain the relative displacement curve and attitude curve of the escape tower and the rocket; d) judging whether there is collision interference in the near field and far field based on the relative displacement curve and attitude curve of the escape tower and the rocket; e) repeating the above steps a) to d) using the determined escape main engine thrust curve; f) considering the escape separation / main engine ignition failure situation, i.e. the escape tower sliding condition without power, setting the escape tower separation power to 0, and repeating the above steps a) to d).

[0050] Step 3.2 Based on the engine mass characteristics designed in Step 2.2 and the internal ballistic curve designed in Step 2.3, conduct a separation dynamics simulation under the escape flight condition to obtain the escape separation trajectory. This step includes: a) giving the simulation input conditions; b) since the escape tower separation under the escape flight condition occurs within the atmosphere, the influence of aerodynamic forces cannot be ignored. The separation dynamics model needs to consider aerodynamic forces, aerodynamic torques, and interstage suction when the return capsule separates from the escape tower; c) the simulation analysis should consider deviation factors; d) use the numerical integration method to perform dynamic simulation and obtain the relative displacement curve and attitude curve of the escape tower and the spacecraft; e) consider the escape tower sliding condition without power, assume that the escape tower and return capsule are no longer physically connected, set the escape tower separation power to 0, and repeat the above steps a) to d).

[0051] Step 4: Separate near-field structural interference and perform far-field collision safety analysis;

[0052] Step 4.1 Based on the normal separation trajectory obtained in Step 3.1 and the escape separation trajectory obtained in Step 3.2, perform near-field structural interference analysis to obtain a conclusion on whether there is near-field interference collision, including: a) calculating the minimum distance between the escape tower and the reentry capsule geometry as a function of time based on the relative distance change curve and the aircraft attitude curve; b) to ensure near-field safety, set a safety distance tolerance. If the minimum value of the minimum distance between the escape tower and the reentry capsule geometry is greater than the minimum value of the minimum distance between the escape tower and the reentry capsule geometry, then the near-field separation is considered safe.

[0053] Step 4.2 Based on the normal separation trajectory obtained in Step 3.1 and the escape separation trajectory obtained in Step 3.2, perform a separation far-field collision risk analysis to obtain a conclusion on whether there is a far-field interference collision, including: judging the separation far-field collision risk based on the changing trend of the relative distance between the escape tower and the return capsule.

[0054] Step 4.3 Based on the conclusions of Step 4.1 regarding whether there is near-field interference or collision and Step 4.2 regarding whether there is far-field interference or collision, the final judgment on the success of the escape separation design is obtained, including: a) statistical separation simulation results; b) if the probability of interference or collision is higher than the allowable value, it is considered that the designed escape separation cannot achieve safe separation of the escape tower, and the axial thrust and lateral thrust of the separation engine need to be corrected.

[0055] Specifically, the method includes the following steps:

[0056] Step 1: Determine the initial values ​​of the escape separation dynamics:

[0057] Step 1.1 First, determine the escape tower separation scheme and the specific separation process:

[0058] Specifically, the escape tower separation scheme uses an escape separation engine with integrated side thrust (thrust not along the axial direction) as the direct power source to provide vector separation power to the escape tower that is far away from the spacecraft in both the axial and lateral directions. The action is executed according to a predetermined sequence, triggered by the information system, and the corresponding power supply provides sufficient current to ignite the pyrotechnics of the escape separation engine, thereby igniting the escape separation engine and making it work.

[0059] In particular, a backup function for the escape main engine is set up to enable emergency separation in the event of a failure of the escape separation engine (the engine will not continue to perform its mission after separation); the escape main engine is located below the escape separation engine, and its thrust is also integrated with the side thrust (the thrust is not along the axial direction);

[0060] Specifically, if both the escape separation engine and the escape main engine are not operating, a powerless escape tower will slide off (relative to the return capsule).

[0061] Generally, the separation process includes the following three stages:

[0062] Phase I: From the start of separation between the escape tower and the return capsule to the point where the escape tower and the return capsule are pulled apart to their maximum longitudinal distance;

[0063] Phase II: From the maximum longitudinal distance between the escape tower and the return capsule, until the escape tower is overtaken by the spacecraft from a longitudinal perspective;

[0064] Phase III: From a longitudinal perspective, the escape tower is overtaken by the spacecraft until it moves to the tail of the rocket, at which point the safe separation from the spacecraft is completed.

[0065] Figure 2 shows a schematic diagram of the initial state and the aforementioned stages.

[0066] Step 1.2 Establishing a simulation model of the escape tower separation dynamics:

[0067] a) Define the coordinate system required for modeling, and establish six-degree-of-freedom motion models for the escape tower and the spacecraft respectively;

[0068] Specifically, the coordinate system definitions required for modeling include the ship's mechanical coordinate system, the nose coordinate system, the geocentric inertial frame, the rocket's own frame, and the escape tower's own frame;

[0069] Specifically, the equations of motion include the center-of-mass kinematics equations, center-of-mass dynamics equations, attitude kinematics equations, and attitude dynamics equations for the escape tower / spacecraft;

[0070] b) Obtain the input conditions for the simulation model, including rocket mass characteristics, spacecraft mass characteristics, escape tower mass characteristics, escape separation engine thrust, rocket separation process attitude information, return capsule aerodynamic characteristics, and escape tower aerodynamic characteristics.

[0071] Specifically, the aforementioned mass characteristics of the aircraft refer to the aircraft's mass (unit: kg), the position of the aircraft's center of mass (unit: mm), and the aircraft's moment of inertia relative to the center of mass (unit: kg / mm). 2 );

[0072] Specifically, escape separation engine thrust refers to the direction of separation thrust relative to the engine axis, the distance from the point of thrust application to the top of the aircraft, and the sea-level thrust data of the separation engine (with time as the independent variable);

[0073] Specifically, the attitude information during rocket separation refers to the displacement of the center of mass in the geocentric frame (unit: m), the velocity of the center of mass in the geocentric frame (unit: m / s), and the Euler angles transformed according to 321 (unit: °), all with time as the independent variable;

[0074] Specifically, the aerodynamic characteristics of the return capsule and the escape tower refer to the changes in the lift coefficient, drag coefficient, and aerodynamic moment coefficient of the aircraft with the angle of attack, Mach number, and altitude.

[0075] c) A dynamic numerical simulation model of the escape tower separation process in the atmosphere was established using the mathematical calculation software Matlab. The numerical integration method and step size were determined according to the simulation accuracy requirements.

[0076] In particular, the aerodynamic effects are significant during the escape tower separation process within the atmosphere, therefore the simulation model must take into account the aerodynamic characteristics of the aircraft;

[0077] d) A dynamic numerical simulation model of the escape tower separation process outside the atmosphere was established using the multibody dynamics software Adams. The model referenced the rocket's motion attitude and drive, assuming the escape tower is subjected to gravity and separation thrust. The established dynamic model is as follows: Figure 3 As shown;

[0078] In particular, due to the thin air outside the atmosphere, the aerodynamic effect can be ignored in the escape tower separation process;

[0079] Specifically, the aerodynamic coefficient is calculated through an interpolation program, and the interpolation method can be linear interpolation, cubic spline interpolation, or other methods.

[0080] Step 1.3 Determine the axial and lateral escape separation thrust parameters:

[0081] a) Select several flight state points as initial conditions for separation simulation based on the nominal flight trajectory of the launch vehicle and the escape trajectory of the escape vehicle;

[0082] b) Decompose the escape separation engine thrust into axial thrust F x and lateral thrust F yDepending on the direction of the lateral thrust, there are two separation modes: upward and downward. The axial thrust causes the escape tower to move away from the spacecraft at the moment of separation, while the lateral thrust causes the escape tower and the spacecraft to have a lateral relative displacement to avoid collision.

[0083] c) Set the amplitude combination of axial thrust and lateral thrust, perform separate simulations under different thrust conditions according to the initial simulation conditions, and record the simulation results;

[0084] d) Based on the simulation results, conduct collision risk analysis (as shown in Table 1) and safety distance analysis (as shown in Table 2) to determine the ideal axial and lateral separation thrust parameters.

[0085] Table 1. Effects of different engine thrust conditions on potential collision behavior (Collision: ×, No collision: ○)

[0086]

[0087]

[0088] Table 2 shows the maximum longitudinal distance between the escape tower and the composite structure in Phase I ( / indicates a collision exists).

[0089]

[0090] Step 2: Detailed Engine Design and Internal Ballistic Prediction

[0091] Step 2.1 Analyze the performance characteristics of the solid rocket motor and specify the technical requirements:

[0092] a) Determine the mission functions of the escape separation engine, including: providing thrust for separation, being able to independently perform the separation of the escape tower and the return capsule from the atmosphere and interior / exterior escape towers, having the ability to ignite simultaneously by the escape tower integrated service unit and the return capsule shoulder integrated service unit, and having the ability to measure and transmit engine combustion chamber pressure.

[0093] b) Determine the environmental conditions that the escape separation engine needs to face, including: the natural environment, the assembly and testing environment, and the spacecraft environment;

[0094] c) Determine the operating mode of the escape separation engine, including: normal flight mission separation and escape flight mission separation;

[0095] d) Determine the performance requirements for the escape separation engine, including: thrust, operating time, engine mass, ambient temperature (covering the worst temperatures at the launch site), atmospheric pressure, electromagnetic compatibility requirements, and mechanical and thermal conditions.

[0096] Step 2.2 Detailed Design of Solid Engine:

[0097] a) Based on the technical requirements of the escape separation engine, determine the specific design of each part of the separation engine, including: casing, combustion chamber, nozzle, safety ignition device, connection structure, etc.

[0098] b) Obtain the propellant shape to provide structural state parameters for the subsequent internal ballistics of the propulsion system; propellant shapes generally include single-hole, multi-hole, star, and wheel shapes.

[0099] Step 2.3 Obtain the ballistic curve within the propulsion system:

[0100] After completing the detailed design of the escape separation engine, the sea-level thrust curve of the separation engine can be obtained through experiments (e.g., Figure 4 As shown); Generally, after the solid rocket motor is manufactured according to the design, the curve of sea-level thrust changing with time is obtained by conducting n (n≥1) ground hot tests, which is the sea-level thrust curve.

[0101] Step 3: Ballistic Separation Simulation

[0102] Step 3.1 Perform escape tower separation dynamics simulation under normal flight conditions based on the separation thrust curve:

[0103] In particular, the escape main engine backup separation condition needs to be considered.

[0104] In particular, the scenario of an escape tower sliding down into the atmosphere without power must be considered.

[0105] a) Given the simulation input conditions, including: separation engine operating time, separation engine thrust, mass characteristics of rocket, spacecraft (two modules), escape tower, etc., the rocket should provide its own attitude information during the separation process, and all parameters should be given the corresponding specific input condition values ​​in the simulation analysis report;

[0106] b) The simulation analysis takes into account deviation factors, including thrust magnitude deviation, thrust skew, thrust eccentricity, and initial separation attitude deviation. Since the escape tower separation occurs outside the atmosphere under normal flight conditions, the influence of aerodynamic forces can be ignored.

[0107] c) Use numerical integration to perform dynamic simulation and obtain the relative displacement curves and attitude curves of the escape tower and the rocket;

[0108] d) Determine whether there is collision interference in the near and far fields based on the relative displacement and attitude curves of the escape tower and the rocket;

[0109] e) Using the determined escape main engine thrust curve, repeat steps a) to d) above;

[0110] f) Considering the escape separation / main engine failure scenario, i.e., the escape tower sliding without power, it is assumed that the escape tower return capsule is no longer physically connected. The escape tower separation power is set to 0, and steps a) to d) above are repeated.

[0111] Step 3.2 Perform escape tower separation dynamics simulation under escape flight conditions based on the separation thrust curve:

[0112] In particular, there is no need to consider the escape main engine backup separation condition, because the escape main engine has already been ignited and used up during the escape.

[0113] In particular, the scenario of an escape tower sliding down into the atmosphere without power must be considered.

[0114] a) Given the simulation input conditions, including: separation engine operating time, separation engine thrust, mass characteristics of the spacecraft return capsule and escape tower, etc., all parameters should be given in the simulation analysis report with corresponding specific input condition values;

[0115] b) Since the escape tower separation occurs within the atmosphere during escape flight, the influence of aerodynamic forces cannot be ignored. The separation dynamics model needs to consider aerodynamic forces, aerodynamic torques, and interstage suction when the return capsule separates from the escape tower.

[0116] c) Simulation analysis should consider deviation factors, including aerodynamic deviation, mass characteristic deviation, thrust magnitude deviation, thrust skew, thrust eccentricity, and initial separation attitude deviation.

[0117] d) Use numerical integration to perform dynamic simulation and obtain the relative displacement curves and attitude curves of the escape tower and the spacecraft;

[0118] e) Considering the scenario of the escape tower sliding without power, assuming that the escape tower return capsule is no longer physically connected, set the escape tower separation power to 0, and repeat steps a) to d) above.

[0119] Step 4: Separate near-field structural interference and analyze far-field collision safety.

[0120] Step 4.1 Separate near-field structure interference analysis:

[0121] a) Calculate the time-varying curve of the minimum distance L between the escape tower and the reentry capsule geometry based on the relative distance change curve and the aircraft attitude curve. If L is always positive, no structural interference will occur; if L is negative, structural interference will occur. See the diagram for a detailed illustration of the near-field separation process. Figure 5 .

[0122] b) To ensure near-field safety during separation, a safety distance tolerance L0 is set. If the minimum distance between the escape tower and the reentry capsule's geometry is L... min If the value is greater than L0, then the near-field separation is considered safe.

[0123] Step 4.2 Separation Far-Field Collision Risk Analysis:

[0124] The risk of a collision in the far field after separation is determined based on the changing trend of the relative distance between the escape tower and the return capsule: if the relative distance gets closer and closer over time, there is a risk of collision; if the relative distance first decreases and then increases over time, the minimum relative distance between the two aircraft is used as the evaluation point. If the minimum relative distance is greater than the set value L1, there is no risk of collision, otherwise there is a risk; if the relative distance increases continuously over time, there is no risk of a collision in the far field after separation. The separation far field process is illustrated in Figures 2(a), 2(b), 2(c), and 2(d).

[0125] Step 4.3 Success assessment of the escape separation design:

[0126] a) According to the statistical separation simulation results, if the probability of interference or collision is lower than the allowable value a%, then the designed escape separation is considered to meet the requirements;

[0127] b) If the probability of interference or collision is higher than the allowable value a%, it is considered that the designed escape separation cannot achieve safe separation of the escape tower, and the axial thrust and lateral thrust of the separation engine need to be corrected.

[0128] This invention solves the urgent problem of escape tower separation design for manned spacecraft. The escape tower separation design method proposed in this invention can adapt to the escape tower separation requirements under normal flight conditions and emergency escape conditions, and realizes the safe separation of the escape tower from the spacecraft under different severe stress conditions during normal flight and escape flight, while coordinating near-Earth / lunar landing missions. The separation design method in this embodiment is scientific, has good implementability, and has certain value for promotion and application.

[0129] Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make possible changes and modifications to the technical solutions of the present invention by utilizing the methods and techniques disclosed above without departing from the spirit and scope of the present invention. Therefore, any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solutions of the present invention shall fall within the protection scope of the technical solutions of the present invention.

Claims

1. A design and verification method for the separation of escape towers for manned spacecraft under different environments, characterized in that... include: Determine the initial values ​​of the escape separation dynamics; Based on the initial value of the escape separation kinetic energy, the technical requirements of the solid rocket motor are obtained. Based on the technical requirements of the solid rocket motor, the solid rocket motor is obtained. The internal ballistic curve of the solid rocket motor is obtained by conducting tests. Based on the mass characteristics and internal ballistic curves of the solid rocket motor technical requirements, separation dynamics simulation under normal flight conditions is carried out to obtain the normal separation trajectory. Based on the mass characteristics and internal ballistic curves of the solid rocket motor technical requirements, separation dynamics simulation under escape flight conditions is carried out to obtain the escape separation trajectory. Based on the normal separation trajectory and the escape separation trajectory, perform near-field structural interference analysis to obtain a conclusion on whether there is near-field interference collision; Based on the normal separation trajectory and the escape separation trajectory, a separation far-field collision risk analysis is conducted to obtain a conclusion on whether there is a far-field interference collision. The success of the escape separation design can be judged based on the conclusions regarding whether near-field and far-field interference collisions occur.

2. The method for designing and verifying the separation of escape towers for manned spacecraft under different environments according to claim 1, characterized in that: Determining the initial values ​​of the escape separation dynamics includes: Determine the specific process of the escape tower separation; A dynamic simulation model of escape tower separation is established based on the specific process of escape tower separation; The initial values ​​of the escape separation dynamics are obtained based on the escape tower separation dynamics simulation model.

3. The method for designing and verifying the separation of a manned spacecraft escape tower under different environments according to claim 2, characterized in that: The specific process of the escape tower separation includes three stages: a) from the start of the separation between the escape tower and the return capsule to the point where the escape tower and the return capsule are separated to their maximum longitudinal distance; b) from the point where the escape tower and the return capsule are separated to their maximum longitudinal distance to the point where the escape tower is overtaken by the spacecraft from a longitudinal perspective; c) from the point where the escape tower is overtaken by the spacecraft from a longitudinal perspective to the point where the escape tower moves to the tail of the rocket, thus completing the safe separation from the spacecraft.

4. The method for designing and verifying the separation of a manned spacecraft escape tower under different environments according to claim 2, characterized in that: The simulation model for the escape tower separation dynamics includes: Define the coordinate system required for modeling; Obtain the input conditions for the simulation model; A dynamic numerical simulation model of the escape tower separation process within the atmosphere was established using the mathematical calculation software Matlab. A dynamic numerical simulation model of the separation process of the extra-atmospheric escape tower was established using the multibody dynamics software Adams.

5. The method for designing and verifying the separation of a manned spacecraft escape tower under different environments according to claim 2, characterized in that: The initial values ​​of escape separation dynamics include axial escape separation thrust parameters and lateral escape separation thrust parameters.

6. The method for designing and verifying the separation of a manned spacecraft escape tower under different environments according to claim 2, characterized in that: The technical requirements for obtaining solid rocket motors include: Determine the mission function of the escape separation engine; Determine the environmental conditions that the escape separation engine must face; Determine the operating mode of the escape separation engine; Determine the performance requirements for the escape separation engine.

7. The method for designing and verifying the separation of a manned spacecraft escape tower under different environments according to claim 6, characterized in that: The escape separation engine's mission functions include: providing separation thrust, being able to independently perform the separation of the escape tower and the return capsule from the atmosphere and interior / exterior, having the ability to ignite simultaneously from the escape tower integrated service unit and the return capsule shoulder integrated service unit, and having the ability to measure and transmit engine combustion chamber pressure. The environmental conditions that escape separation engines need to face include: the natural environment, the assembly and testing environment, and the spacecraft environment; The operating modes of the escape separation engine include: normal flight mission separation and escape flight mission separation; The performance requirements for escape separation engines include: thrust, operating time, engine mass, ambient temperature, atmospheric pressure, electromagnetic compatibility requirements, and mechanical and thermal conditions.

8. The method for designing and verifying the separation of a manned spacecraft escape tower under different environments according to claim 1, characterized in that: Obtaining a normal separation trajectory includes the following steps: (a1) Given the simulation input conditions; (b1) Simulation analysis considers deviation factors; (c1) The dynamic simulation was performed using the numerical integration method to obtain the relative displacement curves and attitude curves of the escape tower and the rocket; (d1) Determine whether there is collision interference in the near and far fields based on the relative displacement curve and attitude curve of the escape tower and the rocket; (e1) Repeat steps (a1) to (d1) using the preset escape main engine thrust curve; (f1) Considering the failure of ignition, which is the unpowered escape tower sliding condition, set the escape tower separation power to 0 and repeat steps (a1) to (d1).

9. The method for designing and verifying the separation of a manned spacecraft escape tower under different environments according to claim 1, characterized in that: Obtaining the escape separation trajectory involves the following steps: (a2) Given the simulation input conditions; (b2) Since the escape tower separation occurs within the atmosphere during escape flight, the influence of aerodynamic forces cannot be ignored. The aerodynamic forces, aerodynamic torques, and interstage suction when the return capsule separates from the escape tower must be considered in the escape tower separation dynamics simulation model. (c2) Simulation analysis should consider deviation factors; (d2) The dynamic simulation was performed using the numerical integration method to obtain the relative displacement curves and attitude curves of the escape tower and the spacecraft; (e2) Considering the unpowered escape tower sliding condition, it is assumed that the escape tower return capsule is no longer physically connected. The escape tower separation power is set to 0, and steps (a2) to (d2) are repeated.

10. The method for designing and verifying the separation of a manned spacecraft escape tower under different environments according to claim 1, characterized in that: Separate near-field structure interferometry analysis includes: The minimum distance L between the escape tower and the return capsule geometry is calculated based on the preset relative distance change curve and the preset aircraft attitude curve. If L is always positive, no structural interference will occur. If L has a negative value, structural interference will occur. To ensure near-field safety during separation, a safety distance tolerance L0 is set. This tolerance is determined by the minimum distance L between the escape tower and the reentry capsule's geometry. min If the value is greater than L0, then the near-field separation is considered safe. The separation far-field collision risk analysis includes: if the relative distance between the escape tower and the return capsule gets closer and closer over time, a collision risk is considered to exist; if the relative distance between the escape tower and the return capsule first decreases and then increases over time, the minimum relative distance between the escape tower and the return capsule is used as the evaluation point. If the minimum relative distance is greater than the set value, there is no collision risk; otherwise, there is a risk. If the relative distance between the escape tower and the return capsule continuously increases over time, there is no separation far-field collision risk.

Images