Separation design and verification method for manned spacecraft escape tower in different environments

Abstract

The invention discloses a manned spacecraft escape tower different-environment separation design and verification method. The method comprises the steps that an escape separation power initial value is determined; obtaining technical requirements of the solid engine according to the escape separation power initial value, obtaining the solid engine according to the technical requirements of the solid engine, and testing the solid engine to obtain an engine inner trajectory curve; acquiring a normal separation trajectory and an escape separation trajectory; according to the normal separation ballistic trajectory and the escape separation ballistic trajectory, performing separation near field structure interference analysis, and obtaining a conclusion whether the near field interferes collision or not; according to the normal separation ballistic trajectory and the escape separation ballistic trajectory, performing separation far-field collision risk analysis, and obtaining a conclusion whether the far field interferes collision or not; and judging whether the escape separation design is successful or not according to the conclusion whether the near field interferes and collides and the conclusion whether the far field interferes and collides. According to the invention, flight safety is guaranteed.

Description

Technical Field

[0001] The invention belongs to the technical field of separation of manned spacecraft escape towers, and in particular relates to a design and verification method for separating different environments of a manned spacecraft escape tower. Background Art

[0002] Manned spacecraft generally adopts the escape tower + whole ship escape scheme, using the escape tower method for escape within the atmosphere and the whole ship escape method after normal tower jettisoning outside the atmosphere. The launch mission is divided into two mission profiles: normal flight mission and emergency escape mission, both of which include the escape tower separation process; in each stage of the normal flight mission, the escape tower separates from the spacecraft after the fairing separates outside the atmosphere; in the emergency flight state of the emergency escape mission within the atmosphere, the escape tower and the spacecraft form a tower return combination (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] In order to ensure flight safety, the escape tower must be separated normally and it must not collide with the spacecraft or the launch vehicle after separation, especially when the escape tower and the return capsule are separated in the atmosphere due to suction that hinders the separation process. Therefore, the design of the escape tower separation scheme and separation safety are important steps in the development of manned spacecraft.

[0004] The separation of the escape tower obviously has different external environments for different mission types (near-Earth missions, lunar missions) and different flight profiles (occurring at altitudes beyond the Karman line of normal flight, and both inside and outside the atmosphere of escape flight). Analysis is carried out for severe working conditions to ensure the safety of the separation scheme design. At the same time, the assessment should cover near-field structural interference, far-field collision, near-field and far-field safety. The near-field refers to the escape tower and the return capsule cannot have structural interference within a few seconds of separation, and the engine jet is affected and damaged. The far-field refers to the trajectory after a certain period of separation cannot collide with the return capsule cabin or the carrier rocket. The existing manned spacecraft escape tower separation design and verification capabilities in different environments need to be refined and improved in accordance with the above capabilities. Summary of the invention

[0005] The technical problem solved by the present invention is: to overcome the deficiencies of the prior art, to provide a design and verification method for separating different environments of a manned spacecraft escape tower, and to ensure flight safety.

[0006] The object of the present invention is achieved through the following technical scheme: a manned spacecraft escape tower separation design and verification method in different environments, comprising: determining an initial value of the escape separation power; obtaining a solid engine technical requirement according to the initial value of the escape separation power, obtaining a solid engine according to the solid engine technical requirement, and testing the solid engine to obtain an engine internal ballistic curve; carrying out a separation dynamics simulation under normal flight conditions according to the mass characteristics in the solid engine technical requirements and the engine internal ballistic curve to obtain a normal separation trajectory; carrying out a separation dynamics simulation under escape flight conditions according to the mass characteristics in the solid engine technical requirements and the engine internal ballistic curve to obtain an escape separation trajectory; carrying out a separation near-field structure interference analysis according to the normal separation trajectory and the escape separation trajectory to obtain a conclusion on whether the near field interferes with the collision; carrying out a separation far-field collision risk analysis according to the normal separation trajectory and the escape separation trajectory to obtain a conclusion on whether the far field interferes with the collision; and judging whether the escape separation design is successful according to the conclusion on whether the near field interferes with the collision and the conclusion on whether the far field interferes with the collision.

[0007] In the above-mentioned manned spacecraft escape tower separation design and verification method in different environments, determining the initial value of the escape separation power includes: determining the specific process of escape tower separation; establishing an escape tower separation dynamics simulation model according to the specific process of escape tower separation; and obtaining the initial value of the escape separation power according to the escape tower separation dynamics simulation model.

[0008] In the above-mentioned design and verification method for separation of the manned spacecraft escape tower in different environments, the specific process of separation of the escape tower includes three stages: a) from the separation of 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 escape tower being caught up by the spacecraft from a longitudinal perspective; c) from the escape tower being caught up by the spacecraft from a longitudinal perspective to the escape tower moving to the tail of the rocket, thereby completing a safe separation from the spacecraft.

[0009] In the above-mentioned manned spacecraft escape tower separation design and verification method in different environments, establishing the escape tower separation dynamics simulation model includes: defining the coordinate system required for modeling; obtaining the input conditions of the simulation model; using the mathematical calculation software Matlab to establish the escape tower separation process dynamics numerical simulation model in the atmosphere; using the multi-body dynamics software Adams to establish the escape tower separation process dynamics numerical simulation model outside the atmosphere.

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

[0011] In the above-mentioned design and verification methods for separation in different environments of the manned spacecraft escape tower, the technical requirements for solid engines include: determining the mission function of the escape separation engine; determining the environmental conditions that the escape separation engine needs to face; determining the working mode of the escape separation engine; and determining the index requirements for the escape separation engine.

[0012] In the above-mentioned design and verification method for separation of the manned spacecraft escape tower in different environments, the mission functions of the escape separation engine include: providing thrust for separation, being able to independently perform the separation mission of the escape tower and the return capsule inside and outside the atmosphere, having the ability to be ignited simultaneously by the escape tower integrated business unit and the return capsule shoulder integrated business unit, and having the ability to measure the engine combustion chamber pressure and transmit data; the environmental conditions that the escape separation engine needs to face include: natural environment, assembly and test environment, and spacecraft environment; the working modes of the escape separation engine include: normal flight mission separation and escape flight mission separation; the index requirements of the escape separation engine include: thrust size, working time, engine mass, ambient temperature, atmospheric pressure, electromagnetic compatibility requirements, and mechanical and thermal conditions.

[0013] In the above-mentioned manned spacecraft escape tower separation design and verification method in different environments, obtaining the normal separation trajectory includes the following steps: (a1) giving simulation input conditions; (b1) considering deviation factors in simulation analysis; (c1) using numerical integration method to perform dynamic simulation to obtain the relative displacement curve and attitude curve between 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 between the escape tower and the rocket; (e1) repeating steps (a1) to (d1) using the preset escape main engine thrust curve; (f1) considering the unignition fault condition, that is, the unpowered escape tower sliding condition, setting the escape tower separation power to 0, and repeating steps (a1) to (d1).

[0014] In the above-mentioned manned spacecraft escape tower separation design and verification method in different environments, obtaining the escape separation trajectory includes the following steps: (a2) giving simulation input conditions; (b2) because the escape tower separation occurs in the atmosphere under the escape flight condition, the influence of aerodynamic force cannot be ignored, and the aerodynamic force, aerodynamic torque and interstage suction when the return capsule separates from the escape tower need to be considered in the escape tower separation dynamics simulation model; (c2) the simulation analysis should consider the deviation factor; (d2) the dynamic simulation is performed using the numerical integration method to obtain the relative displacement curve and attitude curve of the escape tower and the spacecraft; (e2) considering the unpowered escape tower sliding condition, it is assumed that the escape tower and the return capsule are no longer physically connected, the escape tower separation power is set to 0, and steps (a2) to (d2) are repeated.

[0015] In the above-mentioned manned spacecraft escape tower separation design and verification method in different environments, the separation near-field structural interference analysis includes: calculating the time-varying curve of the minimum distance L between the escape tower and the return capsule geometric configuration according to the preset relative distance change curve and the preset aircraft attitude curve. If L is always positive, no structural interference occurs. If L is negative, structural interference occurs. To ensure the safety of the separation near field, a safety distance tolerance L0 is set. If the minimum value L of the minimum distance between the escape tower and the return capsule geometric configuration is min >L0, the separation near-field 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 with time, it is considered that there is a collision risk; if the relative distance between the escape tower and the return capsule first decreases and then increases with time, the minimum relative distance between the escape tower and the return capsule is used as the judgment point. If the minimum relative distance is greater than the set value, it is considered that there is no collision risk, otherwise it is considered that there is a risk; if the relative distance between the escape tower and the return capsule continues to increase with time, it is determined that there is no separation far-field collision risk.

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

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

[0018] (2) The escape tower separation design method proposed in the present invention can adapt to the escape tower separation requirements of normal flight conditions and emergency escape conditions, and realizes the safe separation of the escape tower and the spacecraft under different severe stress conditions of normal flight and escape flight and the coordination of near-Earth / lunar missions. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present invention. Moreover, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0020] Figure 1 It is a flow chart of a design and verification method for separating different environments of a manned spacecraft escape tower provided by an embodiment of the present invention;

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

[0022] FIG2( b ) is a schematic diagram of stage I of the three stages of separation of the escape tower and the return capsule of a manned spacecraft provided by an embodiment of the present invention;

[0023] FIG2( c ) is a schematic diagram of stage II of the three stages of separation of the escape tower and the return capsule of the manned spacecraft provided by an embodiment of the present invention;

[0024] FIG2( d ) is a schematic diagram of stage III of the three stages of separation of the escape tower and the return capsule of the manned spacecraft provided by an embodiment of the present invention;

[0025] Figure 3 is a schematic diagram of a kinetic model provided by an embodiment of the present invention;

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

[0027] Figure 5 It is a schematic diagram of the near-field process of escape tower separation provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0028] Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present disclosure and to be able to fully convey the scope of the present disclosure to those skilled in the art. It should be noted that, in the absence of conflict, the embodiments of the present invention and the features described in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0029] In order to ensure flight safety, the escape tower must be separated normally and it must not collide with the spacecraft or the launch vehicle after separation, especially when the escape tower and the return capsule are separated in the atmosphere due to suction that hinders the separation process. Therefore, the design of the escape tower separation scheme and separation safety are important steps in the development of manned spacecraft.

[0030] There is an obvious need for safety assessment of the separation of the escape tower in different external environments for different mission types (near-Earth missions, lunar missions) and different flight profiles (occurring at altitudes beyond the Karman line of normal flight, and may occur both inside and outside the atmosphere of escape flight). Analysis is carried out for severe working conditions (such as a short interval between separation of the escape tower at zero altitude and parachute opening, poor aerodynamics and easy rollover of the escape tower in the maximum dynamic pressure section, and deviation between the vacuum separation thrust and the ground, etc.) to ensure the feasibility and safety of the separation scheme design. At the same time, the assessment should cover near-field structural interference and far-field collision safety. The near field refers to the fact that there can be no structural interference between the escape tower and the return capsule within a few seconds of separation, and no damage caused by the engine jet. The far field refers to the fact that the trajectory after a certain period of separation cannot collide with the launch vehicle, the return capsule, etc.

[0031] Figure 1 1 is a flow chart of a design and verification method for separating different environments of a manned spacecraft escape tower provided by an embodiment of the present invention. Figure 1 As shown, the method comprises the following steps:

[0032] Determine the initial value of the escape separation power;

[0033] The technical requirements of the solid engine are obtained according to the initial value of the escape separation power, the solid engine is obtained according to the technical requirements of the solid engine, and the solid engine is tested to obtain the engine internal ballistic curve;

[0034] According to the mass characteristics of the solid rocket engine technical requirements and the engine internal ballistic curve, the separation dynamics simulation under normal flight conditions is carried out to obtain the normal separation trajectory;

[0035] According to the mass characteristics of the solid rocket engine technical requirements and the engine internal ballistic curve, separation dynamics simulation under escape flight conditions is carried out to obtain the escape separation trajectory;

[0036] According to the normal separation trajectory and the escape separation trajectory, the separation near-field structure interference analysis is carried out to obtain the conclusion whether the near-field interference collision occurs;

[0037] According to the normal separation trajectory and the escape separation trajectory, the separation far-field collision risk analysis is carried out to obtain the conclusion on whether the far-field interference collision occurs;

[0038] The success of the escape separation design is determined based on the conclusions of whether the near field interferes with the collision and whether the far field interferes with the collision.

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

[0040] Step 1: Determine the initial value of the escape separation power

[0041] Step 1.1 Determine the escape tower separation plan and the specific process of separation, which includes three stages: a) from the beginning of the separation of 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 escape tower being caught up by the spacecraft from a longitudinal perspective; c) from the longitudinal perspective, the escape tower is caught up by the spacecraft, to the escape tower moving to the tail of the rocket, thus completing a safe separation from the spacecraft;

[0042] Step 1.2: According to the escape tower separation scheme and the specific separation process of step 1.1, a escape tower separation dynamics simulation model is established; wherein the escape tower separation dynamics 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 the dynamic numerical simulation model of the escape tower separation process in the atmosphere; d) using the multi-body dynamics software Adams to establish the dynamic numerical simulation model of the escape tower separation process outside the atmosphere;

[0043] Step 1.3: According to the escape tower separation dynamics simulation model of step 1.2, determine the axial and lateral escape separation thrust parameters, which are the initial values ​​of the escape separation power;

[0044] Step 2: Detailed engine design and interior ballistics prediction

[0045] Step 2.1: Based on the initial value of the escape separation power in step 1.3 and in combination with the principle of solid motors, analyze the performance characteristics of solid motors 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 index requirements of the escape separation motor;

[0046] Step 2.2: Based on the technical requirements of the solid motor given in step 2.1, carry out the specific design of the solid motor, including: a) determining the specific plan for separating the various parts of the motor according to the technical requirements of the escape separation motor; b) obtaining the charge shape to provide structural state parameters for the subsequent power system internal ballistics;

[0047] Step 2.3: Based on the design results of step 2.2, obtain the engine internal ballistic curve through an experimental method;

[0048] Step 3: Separation trajectory 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, separation dynamics simulation is carried out under normal flight conditions to obtain a normal separation trajectory. This step includes: a) given simulation input conditions; b) simulation analysis taking into account deviation factors; c) dynamics simulation is performed using a numerical integration method to obtain a relative displacement curve and attitude curve between the escape tower and the rocket; d) based on the relative displacement curve and attitude curve between the escape tower and the rocket, it is determined whether there is collision interference in the near field and the far field; e) using the determined escape main engine thrust curve, repeat the above steps a) to d); f) considering the failure of escape separation / main engine not ignited, that is, the unpowered escape tower sliding condition, the escape tower separation power is set to 0, and the above steps a) to d) are repeated;

[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, separation dynamics simulation is carried out under the escape flight condition to obtain the escape separation trajectory. This step includes: a) given simulation input conditions; b) since the escape tower separation occurs in the atmosphere under the escape flight condition, the influence of aerodynamic force cannot be ignored, and the aerodynamic force, aerodynamic torque and interstage suction when the return capsule separates from the escape tower need to be considered in the separation dynamics model; c) the simulation analysis should consider the deviation factor; d) the dynamics simulation is carried out using the numerical integration method to obtain the relative displacement curve and attitude curve between the escape tower and the spacecraft; e) considering the unpowered escape tower sliding condition, it is considered that the escape tower and the return capsule are no longer physically connected, and the escape tower separation power is set to 0, and the above steps a) to d) are repeated;

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

[0052] Step 4.1 performs separation near-field structure interference analysis based on the normal separation trajectory obtained in step 3.1 and the escape separation trajectory obtained in step 3.2 to obtain a conclusion on whether there is interference collision in the near field, including: a) calculating the time-varying curve of the minimum distance between the escape tower and the return capsule geometric configuration based on the relative distance variation curve and the aircraft attitude curve; b) setting a safety distance tolerance to ensure the safety of the separation near field. If the minimum value of the minimum distance between the escape tower and the return capsule geometric configuration is greater than, the separation near field 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, a separation far-field collision risk analysis is performed to obtain a conclusion on whether there is 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 conclusion of whether there is interference or collision in the near field in step 4.1 and the conclusion of whether there is interference or collision in the far field in step 4.2, finally determines whether the escape separation design is successful, 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 comprises the following steps:

[0056] Step 1: Determine the initial value of the escape separation power:

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

[0058] Specifically, the escape tower separation scheme is that the separation power adopts an escape separation engine with integrated lateral thrust (thrust is not along the axis direction) as direct power, providing the escape tower with vector separation power that is away from the spacecraft in both the axial and lateral directions; the action is performed according to a predetermined sequence, triggered by the information system, and the corresponding power supply provides sufficient current to ignite the escape separation engine pyrotechnics, thereby igniting the escape separation engine to make it work;

[0059] In particular, a backup function for the escape main engine is provided to realize emergency separation under the condition of escape separation engine failure (no mission continued after separation); the escape main engine is located at the lower part of the escape separation engine, and the thrust is also integrated with the side thrust (the thrust is not along the axis direction);

[0060] In particular, if the escape separation engine and the escape main engine are both not working, an unpowered escape tower will slide away (relative to the return capsule).

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

[0062] Phase I: The escape tower and the return capsule begin to separate, until the escape tower and the return capsule are pulled apart to the maximum longitudinal distance;

[0063] Phase II: The maximum longitudinal distance between the escape tower and the reentry capsule is increased until the escape tower is caught up by the spacecraft from a longitudinal perspective;

[0064] Phase III: From a longitudinal perspective, the escape tower is caught up by the spacecraft until it moves to the tail of the rocket, thus completing a safe separation from the spacecraft.

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

[0066] Step 1.2 Establish the escape tower separation dynamics simulation model:

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

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

[0069] Specifically, the equations of motion include the center-of-mass kinematic equation, center-of-mass dynamic equation, attitude kinematic equation, and attitude dynamic equation of the escape tower / spacecraft;

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

[0071] Specifically, the mass characteristics of the above-mentioned aircraft refer to the mass of the aircraft (unit: kg), the position of the center of mass of the aircraft (unit: mm), and the moment of inertia of the aircraft relative to the center of mass (relative to the center of mass, unit: kg.mm 2 );

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

[0073] Specifically, the rocket separation process posture information refers to the displacement of the center of mass under the earth's center (unit: m), the velocity of the center of mass under the earth's center (unit: m / s), and the Euler angle transformed by 321 (unit: °), all with time as the independent variable;

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

[0075] c) Using mathematical calculation software Matlab to establish a numerical simulation model of the dynamics of the escape tower separation process in the atmosphere, the numerical integration method and step size are determined according to the simulation accuracy requirements;

[0076] In particular, the aerodynamic effect is significant during the escape tower separation process in the atmosphere, so the simulation model must consider the aerodynamic characteristics of the aircraft;

[0077] d) The multi-body dynamics software Adams is used to establish a dynamic numerical simulation model of the separation process of the escape tower outside the atmosphere. The motion drive model is based on the motion posture of the rocket. The escape tower is subject to gravity and separation thrust. The established dynamic model is as follows: Figure 3 As shown;

[0078] In particular, since the air outside the atmosphere is thin, the aerodynamic effect can be ignored during the escape tower separation process;

[0079] Specifically, the aerodynamic coefficients are calculated through an interpolation program, and the interpolation method may be a linear interpolation, a cubic spline interpolation, or the like.

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

[0081] a) Selecting 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) Decomposing the escape engine thrust into axial thrust F x and lateral thrust F y, there are two modes of upward separation and downward separation according to the direction of the lateral thrust. The axial thrust makes the escape tower away from the spacecraft at the separation moment, and the lateral thrust makes the escape tower and the spacecraft produce lateral relative displacement to avoid collision;

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

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

[0085] Table 1 Effects of different separation engine thrust conditions on potential collision behavior (collision: × no collision: ○)

[0086]

[0087]

[0088] Table 2 Maximum longitudinal distance between the escape tower and the assembly in stage I ( / represents collision)

[0089]

[0090] Step 2: Detailed engine design and internal ballistics prediction

[0091] Step 2.1 Analyze the performance characteristics of solid rocket motors, given 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 mission of the escape tower and the reentry capsule inside and outside the atmosphere, having the ability to be ignited simultaneously by the escape tower integrated business unit and the reentry capsule shoulder integrated business unit, and having the ability to measure the engine combustion chamber pressure and transmit data;

[0093] b) Determine the environmental conditions that the abort separation engine needs to face, including: natural environment, assembly test environment, and 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 index requirements of the escape separation engine, including: thrust size, operating time, engine mass, ambient temperature (covering the worst temperature of the launch site), atmospheric pressure, electromagnetic compatibility requirements, thermal and mechanical conditions, etc.

[0096] Step 2.2 Specific design of solid rocket engine:

[0097] a) According to the technical requirements of the abort separation engine, determine the specific plan for separating the various parts of the engine, including: casing, combustion chamber, nozzle, safety ignition device, connection structure, etc.;

[0098] b) Obtain the charge shape and provide structural state parameters for the subsequent power system internal ballistics; charge shapes generally include single circular hole shape, multiple circular hole shape, star shape, and wheel shape.

[0099] Step 2.3 Obtain the internal ballistic curve of the dynamic system:

[0100] After the specific design of the escape separation engine is completed, the sea level thrust curve of the separation engine can be obtained through experiments (such as Figure 4 Generally, after the solid engine is manufactured according to the design, it is subjected to n (n≥1) ground hot tests to obtain a curve of sea level thrust changing with time, which is the sea level thrust curve.

[0101] Step 3: Separation trajectory simulation

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

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

[0104] In particular, the unpowered escape tower drop condition in the atmosphere needs to be considered.

[0105] a) Given simulation input conditions, including separation engine working time, separation engine thrust, rocket, spacecraft (two cabins), escape tower and other mass characteristics, the rocket should provide its own posture information during the separation process, and all parameters should be given in the simulation analysis report with corresponding specific input condition values;

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

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

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

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

[0110] f) Consider the failure situation of escape separation / main engine not ignited, that is, the unpowered escape tower sliding condition, it is considered that the escape tower and the return capsule are no longer physically connected, and the escape tower separation power is set to 0, and the above steps a) to d) are repeated.

[0111] Step 3.2: Perform the escape tower separation dynamics simulation under the escape flight condition according to the separation thrust curve:

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

[0113] In particular, the unpowered escape tower drop condition in the atmosphere needs to be considered.

[0114] a) Given simulation input conditions, including separation engine operating time, separation engine thrust, mass characteristics of 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 in the atmosphere during the escape flight condition, the influence of aerodynamic force cannot be ignored. The aerodynamic force, aerodynamic moment and the interstage suction when the reentry capsule separates from the escape tower must be considered in the separation dynamics model;

[0116] c) Deviation factors should be considered in simulation analysis, including aerodynamic deviation, mass characteristic deviation, thrust size deviation, thrust deflection, thrust eccentricity, separation initial attitude deviation, etc.;

[0117] d) Using numerical integration method to perform dynamic simulation and obtain the relative displacement curve and attitude curve between the escape tower and the spacecraft;

[0118] e) Considering the unpowered escape tower sliding down condition, it is assumed that the escape tower and the return capsule are no longer physically connected, and the escape tower separation power is set to 0, and the above steps a) to d) are repeated.

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

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

[0121] a) According to the relative distance change curve and the aircraft attitude curve, the minimum distance L between the escape tower and the return capsule geometric configuration is calculated over time. If L is always positive, no structural interference occurs. If L is negative, structural interference occurs. For details on the separation near-field process, see Figure 5 .

[0122] b) To ensure the safety of the separation near field, a safety distance tolerance L0 is set. If the minimum value L of the minimum distance between the escape tower and the return capsule geometry is min >L0, the separation near field is considered safe.

[0123] Step 4.2 Separation of far-field collision risk analysis:

[0124] The separation far-field collision risk is judged according to the changing trend of the relative distance between the escape tower and the return capsule: if the relative distance becomes closer and closer with time, it is considered that there is a collision risk; if the relative distance first decreases and then increases with time, the minimum relative distance between the two aircraft is used as the judgment point. If the minimum relative distance is greater than the set value L1, it is considered that there is no collision risk, otherwise it is considered that there is a risk; if the relative distance continues to increase with time, it is determined that there is no separation far-field collision risk; the schematic diagram of the separation far-field process is shown in Figures 2(a), 2(b), 2(c) and 2(d) for details.

[0125] Step 4.3 Determine the success of the escape separation design:

[0126] a) Statistical separation simulation results. If the probability of interference or collision is lower than the allowable value a%, 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] The present invention solves the problem of escape tower separation design that needs to be solved urgently for manned spacecraft; the escape tower separation design method proposed in the present invention can adapt to the escape tower separation requirements of normal flight conditions and emergency escape conditions, and realizes the coordination of near-Earth / lunar missions and the safe separation of the escape tower and the spacecraft under different severe stress conditions of normal flight and escape flight; the separation design method of this embodiment is scientific, easy to implement, and has certain promotion and application value.

[0129] Although the present invention has been disclosed as above in the form of a preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art may make possible changes and modifications to the technical solution of the present invention by using the methods and technical contents disclosed above without departing from the spirit and scope of the present invention. Therefore, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention shall fall within the protection scope of the technical solution of the present invention.

Claims

1. A design and verification method for separating different environments of a manned spacecraft escape tower, characterized in that include: Determine the initial value of the escape separation power; The technical requirements of the solid engine are obtained according to the initial value of the escape separation power, the solid engine is obtained according to the technical requirements of the solid engine, and the solid engine is tested to obtain the engine internal ballistic curve; According to the mass characteristics of the solid rocket engine technical requirements and the engine internal ballistic curve, the separation dynamics simulation under normal flight conditions is carried out to obtain the normal separation trajectory; According to the mass characteristics of the solid rocket engine technical requirements and the engine internal ballistic curve, separation dynamics simulation under escape flight conditions is carried out to obtain the escape separation trajectory; According to the normal separation trajectory and the escape separation trajectory, the separation near-field structure interference analysis is carried out to obtain the conclusion whether the near-field interference collision occurs; According to the normal separation trajectory and the escape separation trajectory, the separation far-field collision risk analysis is carried out to obtain the conclusion on whether the far-field interference collision occurs; The success of the escape separation design is determined based on the conclusions of whether the near field interferes with the collision and whether the far field interferes with the collision.

2. The design and verification method for separating different environments of a manned spacecraft escape tower according to claim 1 is characterized by: Determining the initial value of the escape separation power includes: Determine the specific process of escape tower separation; According to the specific process of escape tower separation, a simulation model of escape tower separation dynamics is established; The initial value of the escape separation power is obtained according to the escape tower separation dynamics simulation model.

3. The design and verification method for separating different environments of a manned spacecraft escape tower according to claim 2 is characterized by: The specific process of the escape tower separation includes three stages: a) from the separation of 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 escape tower being caught up by the spacecraft from a longitudinal perspective; c) from the longitudinal perspective, the escape tower is caught up by the spacecraft to the escape tower moving to the tail of the rocket, thus completing a safe separation from the spacecraft.

4. The design and verification method for separating different environments of a manned spacecraft escape tower according to claim 2 is characterized by: The establishment of the escape tower separation dynamics simulation model includes: Define the coordinate system required for modeling; Get the input conditions of the simulation model; The mathematical calculation software Matlab is used to establish a numerical simulation model of the dynamics of the escape tower separation process in the atmosphere; The multi-body dynamics software Adams is used to establish a dynamic numerical simulation model of the separation process of the exoatmospheric escape tower.

5. The design and verification method for separating different environments of a manned spacecraft escape tower according to claim 2 is characterized by: The initial values ​​of the escape separation power include the axial escape separation thrust parameters and the lateral escape separation thrust parameters.

6. The design and verification method for separating different environments of a manned spacecraft escape tower according to claim 2 is characterized by: The technical requirements for solid rocket engines include: Determine the mission functionality of the abort separation motor; Determine the environmental conditions that the abort separation engine will face; Determine the operating mode of the abort separation engine; Determine the performance requirements for the abort separation engine.

7. The design and verification method for separating different environments of a manned spacecraft escape tower according to claim 6 is characterized by: The mission functions of the escape separation engine include: providing thrust for separation, being able to independently perform the task of separating the escape tower and the reentry capsule inside and outside the atmosphere, being capable of simultaneous ignition by the escape tower integrated business unit and the reentry capsule shoulder integrated business unit, and being capable of measuring the engine combustion chamber pressure and transmitting data; The environmental conditions that the escape separation engine needs to face include: natural environment, assembly test environment, and spacecraft environment; The operating modes of the escape separation engine include: normal flight mission separation, escape flight mission separation; The index requirements for the escape separation engine include: thrust size, working time, engine mass, ambient temperature, atmospheric pressure, electromagnetic compatibility requirements, and thermal and mechanical conditions.

8. The design and verification method for separating different environments of a manned spacecraft escape tower according to claim 1 is characterized by: Obtaining a normal separation trajectory includes the following steps: (a1) Given simulation input conditions; (b1) Simulation analysis taking into account deviation factors; (c1) Use numerical integration method to perform dynamic simulation and obtain the relative displacement curve and attitude curve between the escape tower and the rocket; (d1) Determine whether there is collision interference in the near field and far field based on the relative displacement curve and attitude curve between the escape tower and the rocket; (e1) repeating steps (a1) to (d1) using a preset escape main engine thrust curve; (f1) Considering the failure condition of no ignition, i.e. the unpowered escape tower sliding condition, the escape tower separation power is set to 0, and steps (a1) to (d1) are repeated.

9. The design and verification method for separating different environments of a manned spacecraft escape tower according to claim 1 is characterized by: Obtaining the escape separation trajectory includes the following steps: (a2) Given simulation input conditions; (b2) Since the escape tower separation occurs in the atmosphere during the escape flight condition, the influence of aerodynamic forces cannot be ignored. The aerodynamic forces, aerodynamic moments, and the interstage suction when the reentry capsule separates from the escape tower need to be considered in the escape tower separation dynamics simulation model; (c2) The simulation analysis should take into account the deviation factor; (d2) Using numerical integration method to perform dynamic simulation and obtain the relative displacement curve and attitude curve between the escape tower and the spacecraft; (e2) Considering the unpowered escape tower sliding down condition, it is assumed that the escape tower and the return capsule are no longer physically connected, and the escape tower separation power is set to 0, and steps (a2) to (d2) are repeated.

10. The design and verification method for separating different environments of a manned spacecraft escape tower according to claim 1 is characterized by: Separated near-field structure interferometry analysis includes: The time variation curve of the minimum distance L between the escape tower and the return capsule geometric configuration is calculated according to the preset relative distance variation curve and the preset aircraft attitude curve. If L is always positive, no structural interference occurs. If L is negative, structural interference occurs. In order to ensure the safety of the separation near field, a safety distance tolerance L0 is set. If the minimum value L of the minimum distance between the escape tower and the return capsule geometry is min >L0, the separation near field 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, it is considered that 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 judgment point. If the minimum relative distance is greater than the set value, it is considered that there is no collision risk, otherwise it is considered that there is a risk; if the relative distance between the escape tower and the return capsule continues to increase over time, it is determined that there is no separation far-field collision risk.

Images