CN-121997458-A - Carrier rocket safety margin design method, system and processor based on probability calculation

CN121997458ACN 121997458 ACN121997458 ACN 121997458ACN-121997458-A

Abstract

The invention provides a carrier rocket safety margin design method, a carrier rocket safety margin design system and a carrier rocket safety margin design processor based on probability calculation. The invention realizes a forward numerical design method for directly solving the safety margin by the known exhaustion shutdown/track-in probability through probability statistics calculation. The invention does not depend on accumulation of history design experience, and can directly obtain the safety margin through modeling calculation, so that the invention is particularly suitable for research and development of brand new rockets lacking reference models. The invention adopts forward design, thereby fundamentally avoiding the selection of the traditional safety margin cluster and a large number of random targeting iterations, obviously shortening the design period and improving the design efficiency. The method provided by the patent has successfully applied the design of safety margin of various types of carrier rockets, and the effectiveness of the method is verified by multiple simulation results and flight test data.

Inventors

Mi Wenhao
CHEN YU
ZHAO PENGFEI
Mou Yuhan
Jia tianyu
HUANG LONGXIN
WANG YIHUA
WU HAOYU
DAI ZHENG
ZHANG XIAODONG
ZHONG YOUWU

Assignees

蓝箭航天空间科技股份有限公司

Dates

Publication Date: 20260508
Application Date: 20260127

Claims (10)

1. The carrier rocket safety margin design method based on probability calculation is characterized by at least comprising the following steps: Firstly, confirming rocket initial calculation parameters and deviations thereof, presetting a primary exhaustion shutdown probability and a secondary orbit entering probability, designing an initial reference trajectory based on the parameters, and constructing a high-fidelity simulation model comprising closed-loop control on the basis of the reference trajectory and the initial parameters; Step two, introducing a shutdown equation and a guidance law into the simulation model, performing controlled zero-disturbance trajectory simulation, and calculating the existing safety margin of each stage of the rocket; step three, after various errors are introduced into the simulation model, single deviation simulation is carried out, and after ballistic margin deviations of oxygen boxes and fuel boxes of all stages of the rocket are calculated, mean square synthesis is carried out, so that a synthesis result is obtained; Step four, calculating a required safety margin according to the preset primary exhaustion shutdown probability, the secondary orbit entering probability and the synthesized result obtained by calculation in the step three, and redesigning a trajectory according to the calculated required safety margin; Step five, reintroducing a shutdown equation and a guidance law into the simulation model, and carrying out a new round of controlled zero-disturbance trajectory simulation; Step six, generating random deviation comprising a method error, a tool error and a non-guidance error according to a statistical rule, carrying out Monte Carlo random targeting simulation, and counting first-level exhaustion shutdown probability, a falling area range and second-level track entering probability in a simulation result; And step seven, judging whether the first-stage exhaustion shutdown probability, the falling area range and the second-stage in-orbit probability counted in the step six meet the design requirements, outputting a final safety margin design result if the design requirements are met, otherwise, iteratively adjusting the exhaustion shutdown probability and the in-orbit probability preset by each stage of the rocket, returning to the step four, and cycling until the first-stage exhaustion shutdown probability, the falling area range and the second-stage in-orbit probability counted in the step six meet the design requirements, and finally outputting the safety margin result.
2. The method for designing the safety margin of the carrier rocket based on the probability calculation according to claim 1, wherein in the fourth step, the method for calculating the safety margin miu y required by the first-stage oxygen tank is as follows: According to the normal distribution characteristic, the existing safety margin of the rocket primary oxygen tank in the second step is taken as a normal distribution mean value and is marked as miu y, and the synthesis result in the third step is three times of the standard deviation of the normal distribution of the safety margin and is marked as 3sigma1y; according to the formula, P (X1 y < 0) =P (Z1 y < -miu < 1y/sigma1 y) =preset primary oxygen tank exhaustion shutdown probability, and the primary oxygen tank safety margin miu y is needed to be solved; Wherein X1y is the residual mass of the primary oxygen box propellant, and after the X1y is converted into a standard normal distribution form by a variable, Z1y= (X1 y-miu1 y)/sigma 1y is obtained, and then the depletion shutdown probability P (X1 y < 0) is synchronously converted into P (Z1 y < -miu1y/sigma1 y).
3. The method for designing the safety margin of the carrier rocket based on the probability calculation according to claim 2, wherein the first-order oxygen tank is obtained by solving the safety margin miu y, including but not limited to, high-precision calculation by a reverse table look-up (standard normal distribution table Z-table) or a numerical method, and calculation by means of a correlation function in numerical calculation software.
4. The method for designing the safety margin of the carrier rocket based on probability calculation according to claim 3, wherein the sixth step generates random deviation including method error, tool error and non-guidance error according to statistical law, carries out Monte Carlo random targeting simulation, and further comprises the steps of: the first order oxygen box depletion shutdown probability P (X1 y < 0) is calculated according to the normal distribution mean miu y and the standard deviation 3sigma1y by: P (X1 y < 0) =P (Z1 y < -miu < 1y/sigma1 y), solving to obtain the first-order oxygen box depletion shutdown probability.
5. A method for designing a safety margin of a launch vehicle based on probability calculation according to claim 4, wherein the solving method of the first-order oxygen box exhaustion shutdown probability P (X1 y < 0) includes, but is not limited to, high-precision calculation by reverse table look-up (standard normal distribution table Z-table) or numerical method, and calculation by means of correlation function in numerical calculation software.
6. A method of designing a safety margin for a launch vehicle based on probabilistic computation of any one of claims 1 to 5, wherein in step three, the various types of errors introduced in the simulation model include, but are not limited to, process errors, tool errors and other non-guided errors.
7. The method for designing the safety margin of the carrier rocket based on probability calculation according to claim 1, wherein if the rocket is a multi-stage rocket, the depletion shutdown probability and the orbit entering probability of each stage are preset according to the number of rocket stages.
8. A method of designing a safety margin for a launch vehicle based on probabilistic computation of claim 7, comprising performing the designing steps of any one of claims 1-6 for each tank of each stage of rocket.
9. A carrier rocket safety margin design system based on probability calculation, for executing the carrier rocket safety margin design method according to any one of claims 1-8, comprising at least: the initial parameter presetting module is used for confirming rocket initial calculation parameters and deviation thereof, presetting primary exhaustion shutdown probability and secondary orbit entering probability, and designing initial reference trajectory based on the parameters; The simulation calculation module is used for constructing a high-fidelity simulation model containing closed-loop control on the basis of a reference trajectory and initial parameters, introducing a shutdown equation and a guidance law into the simulation model, and performing controlled zero-interference trajectory simulation; The trajectory adjustment module is used for redesigning the trajectory according to the safety margin required by the simulation calculation and transmitting the trajectory to the simulation calculation module; The random targeting simulation module is used for generating random deviation comprising a method error, a tool error and a non-guidance error according to a statistical rule, carrying out Monte Carlo random targeting simulation, and outputting a first-stage depletion shutdown probability, a falling area range and a second-stage track entering probability; The result judging module is used for judging whether the first-stage exhaustion shutdown probability, the falling area range and the second-stage track entering probability output by the random targeting simulation module meet the design requirements or not and generating corresponding judging instructions; The iteration adjusting module is connected with the result judging module and the simulation calculating module and is used for automatically adjusting the depletion shutdown probability and the track entering probability preset by each stage of the rocket when a judging instruction which indicates that the design requirement is not met is received, and feeding back the adjusted parameters to the simulation calculating module to start a new round of simulation, and the iteration adjusting process is continuously carried out until the judging instruction generated by the result judging module indicates that the design requirement is met.
10. A processor configured to run a computer program which, when run, performs the method of designing a safety margin for a launch vehicle according to any one of claims 1 to 8.

Description

Carrier rocket safety margin design method, system and processor based on probability calculation Technical Field The invention relates to the technical field of space launch vehicles, in particular to a method, a system and a processor for designing a safety margin of a launch vehicle based on probability calculation. Background Carrying capacity is the core optimization goal of the overall rocket design. In order to achieve the goal, in the ballistic design of the liquid carrier rocket, a certain safety margin is required to be reserved for key resources such as propellant and the like so as to overcome the influence of various random performance deviations in the flight process, ensure that each stage can be normally shut down according to guidance instructions, and finally meet the design requirements of task reliability and orbit entering probability. Therefore, reasonable safety margin design has important significance for ensuring the success of tasks and optimizing the overall performance of the rocket under the complex deviation condition. At present, a common design thought in the field adopts a reverse verification mode, namely, a series of safety margin configuration schemes are preset according to engineering experience to form a so-called safety margin cluster, then each configuration is randomly targeted through large-scale simulation calculation (such as a Monte Carlo method), the probability of meeting the exhaustion shutdown or accurate track entering is evaluated, and finally, a scheme which meets the requirement of task reliability and has relatively small influence on carrying capacity is selected. This approach essentially approximates the preferred solution by traversal and screening. However, the above approach faces several significant challenges in practical engineering applications. First, the construction of the initial safety margin cluster depends on the prior experience of designers to a great extent, the coverage range and representativeness of different schemes directly influence the rationality of the optimization result, and a systematic forward deducing mechanism is lacked. Secondly, in order to accurately evaluate task success rates corresponding to all schemes, massive random simulation is needed, so that the calculation load is huge, and meanwhile, complicated data interaction and repeated verification are often carried out in the scheme iteration adjustment process, so that the whole design flow period is longer, and the efficiency is limited. The existing safety margin design method still has room for improvement when meeting the overall design requirements of high efficiency and refinement. Therefore, it is needed to provide a forward or systematic design method capable of reducing dependence on experience presetting, reducing simulation computation complexity, and shortening design iteration period, so as to more effectively realize optimization of overall performance of the carrier rocket on the premise of ensuring task reliability. Disclosure of Invention In order to solve the technical problems, the invention provides a carrier rocket safety margin design method, a carrier rocket safety margin design system and a carrier rocket safety margin processor based on probability calculation, and the forward numerical design method for directly solving the safety margin by using the known exhaustion shutdown/orbit entering probability is realized by probability statistics calculation. The invention provides a carrier rocket safety margin design method based on probability calculation, which at least comprises the following steps: Firstly, confirming rocket initial calculation parameters and deviations thereof, presetting a primary exhaustion shutdown probability and a secondary orbit entering probability, designing an initial reference trajectory based on the parameters, and constructing a high-fidelity simulation model comprising closed-loop control on the basis of the reference trajectory and the initial parameters; Step two, introducing a shutdown equation and a guidance law into the simulation model, performing controlled zero-disturbance trajectory simulation, and calculating the existing safety margin of each stage of the rocket; step three, after various errors are introduced into the simulation model, single deviation simulation is carried out, and after ballistic margin deviations of oxygen boxes and fuel boxes of all stages of the rocket are calculated, mean square synthesis is carried out, so that a synthesis result is obtained; Step four, calculating a required safety margin according to the preset primary exhaustion shutdown probability, the secondary orbit entering probability and the synthesized result obtained by calculation in the step three, and redesigning a trajectory according to the calculated required safety margin; Step five, reintroducing a shutdown equation and a guidance law into the simulation model, and carrying out a new round of controlled