Aerospace product quality characteristic analysis method

Abstract

The invention relates to an aerospace product quality characteristic analysis method. The method comprises the following steps: converting a user demand into a key overall technical target of a system-level product; converting the key overall technical target into a key technical target of a subsystem-level product; converting the key technical target into a key target of a single machine, components and products which can be purchased; and summarizing the key overall technical targets, the key technical targets and the key targets to form a summary table of the product quality characteristics. According to the method provided by the invention, the product characteristics can be reasonably transmitted and decomposed to each level, so that the reliability and applicability of the final product are ensured.

Description

Technical Field

[0001] The invention belongs to the technical field of product quality, and in particular relates to a method for analyzing the quality characteristics of aerospace products based on overall technical goal sorting. Background Art

[0002] With the rapid development of modern industry, especially in the aerospace field, the identification and analysis of product quality characteristics have become particularly important. Due to its complex system level and highly customized requirements, aerospace products require comprehensive and scientific quality characteristics analysis in the early stages of design. This not only includes identifying key quality characteristics, but also involves how to reasonably transfer and decompose these characteristics to each product level to ensure the reliability and applicability of the final product.

[0003] However, the existing quality characteristic analysis methods often fail to fully consider the special needs of aerospace products and lack systematic analysis tools to support such multi-level analysis and control. Therefore, a method based on quality function deployment combined with failure mode effect analysis is proposed to address the deficiencies in existing technologies. Summary of the invention

[0004] The present invention aims to solve one of the technical problems existing in the prior art to at least a certain extent. To this end, the present invention provides a method for analyzing the quality characteristics of aerospace products.

[0005] According to one aspect of the present invention, there is provided a method for analyzing the quality characteristics of aerospace products, which is characterized by comprising: converting user requirements into key overall technical objectives of system-level products; converting the key overall technical objectives into key technical objectives of subsystem-level products; converting the key technical objectives into key objectives of single machines, parts and components, and even procurable products; and summarizing the key overall technical objectives, the key technical objectives, and the key objectives to form a summary table of the product quality characteristics.

[0006] Preferably, converting user needs into key overall technical goals of system-level products includes: establishing an aerospace product quality characteristics analysis team; determining user needs; determining overall technical goals; and determining the key overall technical goals of the system-level product based on the user needs and the overall technical goals.

[0007] Preferably, determining the first-level user needs includes: classifying user requirements, simplifying the user requirements and defining them as first-level requirements; classifying the first-level requirements, simplifying the first-level requirements until the user requirements are expressed in a hierarchical manner, and determining the final result as the first-level user needs, and the number of content repetitions is used as the importance of the first-level user needs; wherein the first-level user needs meet the following conditions: the terms are concise and unambiguous; a user need only expresses a specific meaning; the corresponding task goal is not regarded as a user need; it is easy for engineering personnel to understand; user needs at the same level are independent of each other, and there is no duplication or overlap in content.

[0008] Preferably, determining the second-level user needs includes: conducting a systematic functional requirement analysis based on the functional objectives in the aerospace product mission book or technical documents to determine the performance parameters of the product; collecting relevant test information of the product, including test points, test items, test plans and fault sample sets; quantitatively analyzing the relationship between the performance parameters of the aerospace product and the relevant test information, and calculating the test coverage; for parameters that cannot be directly tested, classifying them as Class I unmeasurable parameters; for parameters that can only be tested in lower-level products, classifying them as Class II unmeasurable parameters; for parameters that can only be tested in upper-level products, classifying them as Class III unmeasurable parameters; taking the Class I unmeasurable parameters, the Class II unmeasurable parameters and the Class III unmeasurable parameters as the second-level user needs, and taking the test coverage level as the importance of the second-level user needs.

[0009] Preferably, determining the third-level user needs includes: dividing the mission phases of the aerospace product according to the aerospace product mission book or technical documents, constructing a functional framework diagram and a structural framework diagram, and generating a reliability framework diagram; performing failure mode analysis on the structure and function of the aerospace product; determining whether the failure mode belongs to a critical type or a success-failure type; analyzing the failure mode according to the classification of the failure mode, applying fault tree analysis to identify the root cause and hierarchical relationship of the failure; generating a list of single-point failure modes, listing all single-point failure modes that may cause the overall failure of the system; determining whether the single-point failure mode can be eliminated through redundant components or design improvement measures, and taking corresponding measures; when the result is no, identifying the design parameters related to the single-point failure mode; the design parameters identified by the single-point failure mode are used as the third-level user needs, and the failure severity obtained by analysis is used as the importance of the third-level user needs.

[0010] Preferably, the overall technical objectives include a mission profile and corresponding functional and interaction objectives, wherein the mission profile is determined by the following steps: dividing the mission phases into a launch phase, a state establishment and on-orbit testing phase, and an on-orbit flight phase; determining key events for each mission phase; determining key tasks to be done for key events in each mission phase; determining the environment in which aerospace products are located in each mission phase, including force, heat, and space environment; and determining the duration of each mission phase.

[0011] Preferably, the functional objectives are determined by the following steps: constructing requirements for system tasks and functions at each stage of the mission profile; constructing functional requirements for applied models; constructing functional requirements for models to be applied; and constructing a list of existing functional requirements.

[0012] Preferably, the interaction target is determined by the following steps: listing the technical targets in the rows and columns of the correlation matrix to form a basic matrix framework; identifying the interaction relationship between each pair of technical targets, including positive correlation, strong positive correlation, negative correlation, strong negative correlation and no correlation; filling in the corresponding relationship symbols in the cross cells of the correlation matrix to form a complete relationship matrix; analyzing the constructed correlation matrix, evaluating the coordination and repeatability between the technical targets, ensuring that there are no redundant technical targets, and making necessary adjustments based on the analysis results.

[0013] Preferably, according to the user requirements and the overall technical objectives, the key overall technical objectives of the system-level product are determined, including: determining the best overall technical objective (best TM) and the worst overall technical objective (worst TM) for each of the user requirements (CR); specifying the priority of the best TM relative to other overall technical objectives (other TMs), using a numerical range of 1 to 9 to represent the importance of the best TM relative to other TMs, and generating a priority vector from the best to other overall technical objectives for comparison; specifying the priority of other TMs relative to the worst TM, using a numerical range of 1 to 9 to represent the importance of other TMs relative to the worst TM, and generating a priority vector from other overall technical objectives to the worst overall technical objectives for comparison; establishing an optimization model based on the priority vector to optimize the weight distribution of the overall technical objectives; determining the weight of the overall technical objectives under each of the user requirements (CR) by solving the optimization model; verifying the accuracy of the weight distribution, and when the weight distribution is accurate, using the weight distribution result of the overall technical objectives as the basis for decision-making on key overall technical objectives.

[0014] Preferably, an optimization model is established based on the priority vector to determine the weight of the overall technical goal under each of the user requirements (CR), including: applying the priority vector from the best to other overall technical goals for comparison and the priority vector from other overall technical goals to the worst overall technical goal for comparison to the following model:

[0015]

[0016] w B is the weight of the optimal overall technical goal, w W is the weight of the worst overall technical goal, w j is the weight of other overall technical goals, a Bj is the comparison result of the best overall technical goal relative to other overall technical goals, a wj is the comparison result of other overall technical objectives relative to the worst overall technical objective; solve the above model to minimize the differences in all pairwise comparisons to determine the optimal weight of each overall technical objective.

[0017] Preferably, verifying the accuracy of the weight distribution includes: (1) determining whether equation a Bj ×a wj =a BW Is it true, where a BW is the comparison result of the best overall technical goal relative to the worst overall technical goal; (2) If the above conditions are not met, the correction parameter ξ is used to adjust; (a Bj -ξ)×(a Wj -ξ)=a BW +ξ, judge whether the result of ξ\CI meets the preset threshold, the threshold is defined as 0.1, the CI value is BW If any of (1) or (2) is satisfied, the weight distribution is defined as accurate.

[0018] Preferably, the key overall technical goals of the system-level product are determined according to the user needs and the overall technical goals, including: sorting the overall technical goals from most important to least important according to the degree of influence of each overall technical goal on the decision-making goal; performing pairwise comparisons on the overall technical goals to generate a comparison priority vector; establishing an optimization model based on the comparison priority vector to ensure that the ratio between weight coefficients is equal to the comparison priority of the overall technical goals and satisfies the mathematical transitivity condition; solving the optimization model to determine the optimal weight of each overall technical goal while minimizing the amount of consistency deviation; and using the solved weights as the basis for decision-making on key overall technical goals.

[0019] Preferably, the overall technical objectives are compared in pairs to generate a comparison priority vector, including: the comparison priority vector is β=(β 1 / 2 ,β 2 / 3 ,…,β k / (k+1) ), where β k / (k+1) Represents the priority of the kth overall technical goal relative to the k+1th overall technical goal.

[0020] Preferably, establishing the optimization model and solving the optimization model include: confirming that the ratio of weight coefficients is equal to the priority between the overall technical objectives: r k represents the weight coefficient of the kth overall technical goal, r k+1 Represents the weight coefficient of the k+1th overall technical goal; confirm that it satisfies the mathematical transitivity law: β k / (k+1)× β (k+1) / (k+2)＝ β k / (k+2)；

[0021] The optimal weight value of the overall technical goal is determined by minimizing φ:

[0022] Preferably, the key technical objectives of the subsystem-level products include: establishing an aerospace product quality characteristics analysis team; determining the system-level key quality characteristics that need to be decomposed and transferred; determining the subsystem-level product technical objectives; and determining the key technical objectives of the subsystem-level products based on the system-level key quality characteristics and the subsystem-level product technical objectives.

[0023] Preferably, the key technical objectives are converted into key objectives of single machines, parts and components, and even procureable products, including: establishing an aerospace product quality characteristics analysis team; determining key technical objectives of subsystem-level products that need to be decomposed and transferred; determining technical objectives of single machines, parts and components, and even procureable products; determining key objectives of single machines, parts and components, and even procureable products based on the key technical objectives of the subsystem-level products and the key objectives of the single machines and parts and components.

[0024] According to one aspect of the present invention, there is provided an analysis system for the quality characteristics of aerospace products, comprising: a user demand conversion module for converting user demand into key overall technical objectives of system-level products; a key overall technical objective conversion module for converting the key overall technical objectives into key technical objectives of subsystem-level products; a key technical objective conversion module for converting the key technical objectives into key objectives of single machines, parts and components, and even procurable products; and a summary module for summarizing the key overall technical objectives, the key technical objectives, and the key objectives to form a summary table of the product quality characteristics.

[0025] Preferably, the user demand conversion module includes: an analysis team creation module for creating an aerospace product quality characteristic analysis team; a user demand identification module for determining the user demand; an overall technical goal determination module for determining the overall technical goal; and a key overall technical goal determination module for determining the key overall technical goal of the system-level product based on the user demand and the overall technical goal.

[0026] Preferably, the user demand identification module is used to determine the first user demand, including: a user requirement classification module, used to classify user requirements and simplify the user requirements into first super-level requirements; a first super-level requirement processing module, used to classify and simplify the first super-level requirements until the user requirements are expressed in a hierarchical manner, and the final result is determined to be the first user demand, and the importance of the first user demand is determined by the number of times the content is repeated; a demand standard compliance module, used to ensure that the first user demand meets the following conditions: the language is concise and unambiguous; each user demand only expresses one specific meaning; the task goal is not used as a user demand; it is easy for engineering personnel to understand; user requirements at the same level are independent and the content is not repeated or overlapped.

[0027] Preferably, the user requirement identification module is used to determine the second user requirement, including: a functional goal analysis module, which is used to perform a systematic functional requirement analysis based on the functional goals in the aerospace product mission book or technical documents to determine the performance parameters of the product; a test information collection module, which is used to collect relevant test information of the product, including test points, test items, test plans and fault sample sets; a quantitative analysis module, which is used to quantitatively analyze the relationship between the performance parameters of aerospace products and related test information, and calculate the test coverage; a parameter classification module, which is used to classify parameters that cannot be tested directly as Class I unmeasurable parameters; classify parameters that can only be tested in lower-level products as Class II unmeasurable parameters; classify parameters that can only be tested in upper-level products as Class III unmeasurable parameters; a requirement determination module, which is used to take the Class I unmeasurable parameters, Class II unmeasurable parameters and Class III unmeasurable parameters as the second user requirement, and take the test coverage level as the importance of the second user requirement.

[0028] Preferably, the user demand identification module is used to determine the third user demand, including: a mission phase division module, which divides the mission phases of aerospace products according to the aerospace product mission book or technical documents, constructs a functional framework diagram and a structural framework diagram, and generates a reliability framework diagram; a failure mode analysis module, which performs failure mode analysis on the structure and function of aerospace products; a failure mode classification module, which determines whether the failure mode belongs to a critical type or a success or failure type; a fault tree analysis module, which analyzes the failure mode according to the classification of the failure mode and applies fault tree analysis to identify the root cause and hierarchical relationship of the failure; a single point failure mode generation module, which generates a single point failure mode list, listing all single point failure modes that may cause the overall failure of the system; a redundancy elimination judgment module, which determines whether the single point failure mode can be eliminated through redundant components or design improvement measures, and takes corresponding measures; a design parameter identification module, which identifies the design parameters related to the single point failure mode when the result is no; a design parameter output module, which uses the design parameters identified by the single point failure mode as the third user demand, and uses the fault severity obtained by analysis as the importance of the third user demand.

[0029] Preferably, the overall technical objectives include a mission profile, and corresponding functional and interaction objectives, wherein the mission profile is determined by the following modules: a mission phase division module, which divides the mission into a launch phase, a state establishment and on-orbit test phase, and an on-orbit flight phase; a key event determination module, which determines the key events of each mission phase; a key work determination module, which determines the key work that needs to be performed for the key events of each mission phase; an environment determination module, which determines the environment in which the aerospace product is located in each mission phase, including force, heat, and space environment; and a time determination module, which determines the duration of each mission phase.

[0030] Preferably, the functional objectives are determined by the following modules: a system task requirement building module, which builds the requirements for system tasks and functions at each stage of the task profile; an applied model functional requirement building module, which builds the functional requirements of the applied model; an expected application model functional requirement building module, which builds the functional requirements of the expected application model; an existing functional requirement list building module, which builds a list of existing functional requirements.

[0031] Preferably, the interaction targets are determined by the following modules: a basic matrix framework construction module, which lists the technical targets in the rows and columns of the correlation matrix to form a basic matrix framework; an interaction relationship identification module, which identifies the interaction relationship between each pair of technical targets, including positive correlation, strong positive correlation, negative correlation, strong negative correlation and no correlation; a relationship matrix construction module, which fills the corresponding relationship symbols in the cross cells of the correlation matrix to form a complete relationship matrix; a coordination analysis module, which analyzes the constructed correlation matrix, evaluates the coordination and repeatability between the technical targets, ensures that there are no redundant technical targets, and makes necessary adjustments based on the analysis results.

[0032] Preferably, the key overall technical goal determination module includes: a user demand analysis module, which determines the best overall technical goal (best TM) and the worst overall technical goal (worst TM) for each user demand (CR); a priority determination module, which specifies the priority of the best TM relative to other overall technical goals (other TMs), uses a numerical range of 1 to 9 to represent the importance of the best TM relative to other TMs, and generates a priority vector; a priority vector generation module, which specifies the priority of other TMs relative to the worst TM, and generates a priority vector from other overall technical goals to the worst overall technical goal for comparison; an optimization model establishment module, which establishes an optimization model based on the priority vector to optimize the weight distribution of the overall technical goals; a weight verification module, which determines the weight of the overall technical goal under each user demand (CR) by solving the optimization model, and verifies the accuracy of the weight distribution. When the weight distribution is accurate, it is used as the basis for the decision of the key overall technical goal.

[0033] Preferably, the optimization model building module includes: an optimization target setting unit, which applies the priority vector from the best to other overall technical targets for comparison and the priority vector from other overall technical targets to the worst overall technical target for comparison to the following model:

[0034]

[0035] Weight definition unit, defines each weight: w B is the weight of the optimal overall technical goal, w W is the weight of the worst overall technical goal, w j is the weight of other overall technical goals, a Bj is the comparison result of the best overall technical goal relative to other overall technical goals, a wj It is the comparison result of other overall technical objectives relative to the worst overall technical objective; the solution module minimizes the differences in all pairwise comparisons by solving the above model, thereby determining the optimal weight of each overall technical objective.

[0036] Preferably, the weight verification module includes: an equation judgment unit for judging equation a Bj ×a wj =a BW Is it true, where a BW is the comparison result of the best overall technical goal with the worst overall technical goal; the correction parameter unit, when the above conditions are not met, adjust (a Bj -ξ)×(a Wj -ξ)=a BW +ξ; a threshold judgment unit, which judges whether the value of the modified ξ\CI meets a preset threshold, wherein the threshold is defined as 0.1, and the CI value is BW Association; weight confirmation unit, if any of the above conditions is met, it is defined as accurate weight distribution, ensuring the effectiveness and reliability of the optimization results.

[0037] Preferably, the key overall technical goal determination module includes: a goal sorting unit, which is used to sort the overall technical goals from most important to least important, based on the degree of influence of each overall technical goal on the user needs; a pairwise comparison unit, which is used to compare the overall technical goals in pairs and generate a comparison priority vector; an optimization model establishment unit, which establishes an optimization model according to the comparison priority vector to ensure that the ratio between weight coefficients is equal to the comparison priority of the overall technical goal and satisfies the mathematical transitivity condition; a model solving unit, which determines the optimal weight of each overall technical goal by solving the optimization model while minimizing the amount of consistency deviation; a weight confirmation unit, which uses the solved weight as the basis for decision-making on key overall technical goals to improve the accuracy and effectiveness of system analysis.

[0038] Preferably, the overall technical objectives are compared in pairs to generate a comparison priority vector, including: the comparison priority vector is β=(β 1 / 2 ,β 2 / 3 ,…,β k / (k+1) ), where β k / (k+1) Represents the priority of the kth overall technical goal relative to the k+1th overall technical goal.

[0039] Preferably, establishing the optimization model and solving the optimization model include: confirming that the ratio of weight coefficients is equal to the priority between the overall technical objectives: r k represents the weight coefficient of the kth overall technical goal, r k+1 Represents the weight coefficient of the k+1th overall technical goal; confirm that it satisfies the mathematical transitivity law: β k / (k+1)× β (k+1) / (k+2)＝ β k / (k+2);Determine the optimal weight value of the overall technical goal by minimizing φ:

[0040] Preferably, the key overall technical goal conversion module includes: an aerospace product quality characteristics analysis team, which is responsible for determining the system-level key quality characteristics that need to be decomposed and transferred; a subsystem-level product technical goal determination unit, which is used to determine the technical goals of subsystem-level products; and a key technical goal determination unit, which determines the key technical goals of subsystem-level products based on the system-level key quality characteristics and subsystem-level product technical goals.

[0041] Preferably, the key technical target conversion module includes: an aerospace product quality characteristic analysis team, which is responsible for determining the key technical targets of subsystem-level products that need to be decomposed and transferred; a single machine and component technical target determination unit, which is used to determine the technical targets of single machines, components and even procureable products; a key target determination unit, which determines the key targets of single machines, components and even procureable products based on the key technical targets of the subsystem-level products and the key targets of the single machines and components.

[0042] Compared with the prior art, the present invention has the following beneficial effects:

[0043] Quality function deployment is a systematic method widely used in product design and development to transform customer needs into technical characteristics of products, thereby improving design quality and shortening product development cycles. In the process of quality function deployment, customer needs are linked to technical measures through a relationship matrix to form an overall design plan for the product. However, in the traditional method of building a relationship matrix, the allocation of weights usually relies on expert opinions, and the scoring criteria used are subjective and may lead to inconsistencies and incorrect rankings of technical measures.

[0044] In the prior art, in order to solve this problem, researchers have proposed some decision-making methods based on pairwise comparison, such as the analytic hierarchy process (AHP) and the analytical network process (ANP), to improve weight allocation. However, these methods usually require a large amount of pairwise comparison data, which is time-consuming and prone to inconsistency. In addition, with the increase of design complexity, the comparison tasks in traditional methods increase exponentially, which is not conducive to the rapid weight allocation of large projects.

[0045] In order to improve the efficiency and accuracy of weight assignment in the relationship matrix, the improved method of this patent improves the efficiency of the weight assignment process by reducing the number of comparisons and using vectorized pairwise comparisons and consistency measures, ensuring the accuracy of the technical measure ranking and significantly reducing data collection and processing time.

[0046] In addition, in general, quality function deployment is a method of forward analysis based on user needs, while other methods are methods of reverse analysis based on problems, failures, and risks. These methods have different analysis angles, so they can be complementary and used in combination. Since system and subsystem products are relatively complex, it is necessary to use a variety of technologies to fully analyze and identify the key quality characteristics of products from different angles. Not only the impact of user requirements on product quality should be considered, but also various risks that may occur in the product, including risks caused by failures and unpredictability, risks caused by deviations from previous successful data, and risks caused by interactive effects of product dimensions. For single-machine and component products, which are relatively simple, the quality function deployment method can identify the key quality characteristics of the product, and other methods can also be used for reference.

[0047] The method proposed in this patent is integrated and applied in the various links on the left side of the "V" model of aerospace product development, that is, in the process of decomposing from user requirements to various product levels and even procurable products. The quality function deployment method is used as the basic method, and the results of the analysis of various other methods are brought into the "left wall" of the quality function deployment method for analysis, and the input content of the "left wall" is gradually reduced from the system, subsystem, single machine, and parts and components. This method is mainly used to support the identification and analysis of key and important characteristics in GJB190 "Characteristic Identification" and QJ 892A "Aerospace Product Characteristic Classification and Management Requirements", and provides a set of quantitative analysis methods to analyze the degree of influence of product quality characteristics at all levels on the quality of the final product, and efficiently and accurately identify and analyze user needs as key quality characteristics of products at all levels, so as to focus on the key quality characteristics identified and analyzed, so that the product design can meet the requirements of the end users.

[0048] Mainly used in the following aspects:

[0049] (1) Transforming user requirements into key overall technical goals;

[0050] (2) Transforming key overall technical objectives into key technical objectives for subsystem-level products;

[0051] (3) The key technical objectives at the subsystem level are converted into key technical objectives for individual machines, components, and eventually procureable products. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of this application. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0053] Figure 1 A schematic diagram of a flow chart according to an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0054] The following examples are provided to allow those skilled in the art to more clearly understand the present invention. It should be noted that the following examples do not limit the scope of protection claimed in the present invention and are only illustrative examples. The raw materials, reagents or devices mentioned in the following examples, unless otherwise specified, can be obtained from commercial sources or by known existing methods.

[0055] The present invention provides an analysis method for the quality characteristics of aerospace products, comprising: converting user needs into key overall technical goals of system-level products; converting the key overall technical goals into key technical goals of subsystem-level products; converting the key technical goals into key goals of single machines, parts and components, and even procurable products; summarizing the key overall technical goals, the key technical goals, and the key goals to form a summary table of the product quality characteristics.

[0056] The present invention proposes steps for analyzing the quality characteristics of aerospace products, including: step one: identifying and analyzing key quality characteristics of system-level products, converting user requirements into key overall technical goals; step two: identifying and analyzing key quality characteristics of subsystem-level products, converting key overall technical goals into key technical goals of subsystem-level products; step three: identifying and analyzing key quality characteristics of stand-alone and component products, converting key subsystem body technical goals into key goals of stand-alone, component and other products; step four: compiling a summary table of key quality characteristics of products.

[0057] The analysis starts with user demand analysis. The results of each step of analysis are the input to the next step, and finally form the key quality characteristics of each level of products. In each step, the analysis is carried out according to the product level and development stage applicable to various methods. Based on the analysis of multiple methods, integrated processing is carried out to obtain the key quality characteristics of each product level.

[0058] According to another embodiment of the present invention, the key overall technical objectives of converting user needs into system-level products include: establishing an aerospace product quality characteristics analysis team: the development and production of aerospace products are relatively complex, and a comprehensive product key quality characteristics analysis team needs to be established during the demonstration stage, involving personnel from various relevant departments such as planning management, development and design, process, manufacturing, equipment supply, quality management, process equipment, and military representatives (which can be increased or decreased as needed). In order to more fully analyze and accurately grasp user needs (including basic needs and potential needs), user representatives should be invited to participate in the analysis team as much as possible under certain conditions, and product quality and reliability information obtained from various channels should be fully utilized.

[0059] Determine user needs, including forward analysis and reverse analysis to determine user needs:

[0060] Positive analysis to determine user needs, It includes: classifying user requirements, simplifying the user requirements and defining them as first-level requirements; classifying the first-level requirements, simplifying the first-level requirements until the hierarchical expression of user requirements is achieved, determining the final result as user needs, and the number of repeated contents as the importance of user needs; wherein user needs meet the following conditions: the terms are concise and unambiguous; a user need only expresses a specific meaning; the corresponding task objectives are not regarded as user requirements; it is easy for engineering personnel to understand; user needs at the same level are independent of each other, and there is no duplication or overlap in content.

[0061] User needs are the most basic input for analysis at this stage, and the quality function should be started with the investigation of demand quality, including user model development needs, including combat environment needs, tactical and technical performance needs, combat use needs, development and production conditions, large-scale test conditions, development cycle and development support conditions, product quality tracking and collection and analysis of fault information, national and industry policies, regulations, specifications and standards, as well as environmental, health, safety and other requirements. Aerospace products have the following special features compared to general products:

[0062] a. The user base is relatively single, and the collection of user needs is highly targeted, which is different from the practice of randomly sampling users to solicit opinions in the home appliance industry; b. The production batch is small, and user demand surveys are conducted for specific types of products; c. Users are mostly groups, and their senior leaders have the decision-making power; d. Data packets of similar products are recorded and can be used as a basis for meeting user needs.

[0063] User needs usually come from the following sources:

[0064] a. Tactical and technical objectives or development task book stipulated in the contract, including overall performance objectives, technical objectives, interface requirements, etc.; b. Investigation and consultation with the user department; c. Relevant regulations, standards, specifications, and technical management documents for similar products; d. Results of research by professional institutions and the industry; e. Information on similar foreign products; f. Bidding process.

[0065] Some of the requirements obtained through the above channels are unclear or even scattered, involving quality, performance, price, life, reliability, maintainability, safety and other aspects. The product quality characteristics analysis team should use the affinity diagram method to sort out, process and refine the unsystematic user requirements obtained through the above channels, and convert them into a language suitable for design and production, and finally sort out the user requirements. The specific steps are as follows:

[0066] a. Fill in the requirements obtained through the above methods on small pieces of paper, and remove the pieces with repeated content; b. Classify the pieces of paper with similar content, summarize their meanings in concise language, and write them on new pieces of paper as higher-level requirements; c. Classify the new pieces of paper according to the degree of similarity of the content, and repeat the previous step until the quality of the requirements is expressed in a hierarchical manner.

[0067] There are certain requirements for the expression of user needs, mainly:

[0068] a. The terms are concise and unambiguous; b. A user requirement only expresses one specific meaning; c. The corresponding task goal (technical solution) is not regarded as a user requirement; d. It is easy for engineering personnel to understand; e. User requirements at the same level are independent of each other, and there is no duplication or overlap in content.

[0069] For simple products, user requirements are often only one level. For slightly more complex products, in order to analyze the user's requirements for the product in depth and detail, multiple levels of user requirements may be established, see Table 7. When conducting product quality characteristic analysis, it is sufficient to extract the first 2 or 3 levels of user requirements. There should not be too many user requirement items, otherwise it will affect work efficiency. If necessary, the level of product quality characteristic analysis can be increased or divided into several parallel analysis levels for expansion, or some user requirements and task goals with minor impact can be deleted, or they can be merged to a certain extent to reduce the scale of analysis.

[0070] User requirements for a certain aircraft

[0071]

[0072]

[0073] Reverse analysis to determine user needs:

[0074] Determine the second-level user needs, including: based on the functional goals in the aerospace product mission book or technical documents, conduct a systematic functional requirement analysis to determine the performance parameters of the product; collect relevant test information of the product, including test points, test items, test plans and fault sample sets; quantitatively analyze the relationship between the performance parameters of the aerospace product and the relevant test information, and calculate the test coverage; for parameters that cannot be tested directly, determine that they are classified as Class I unmeasurable parameters; for parameters that can only be tested in lower-level products, classify them as Class II unmeasurable parameters; for parameters that can only be tested in upper-level products, classify them as Class III unmeasurable parameters; regard the Class I unmeasurable parameters, the Class II unmeasurable parameters, and the Class III unmeasurable parameters as the second-level user needs, and use the test coverage level as the importance of the second-level user needs.

[0075] This embodiment conducts a system functional requirement analysis based on the functional objectives in the mission book or technical documents of the aerospace product, determines the performance parameters of the aerospace product, and determines the different parameter classifications of the product during the test process by analyzing the test information and calculating the test coverage. The detailed steps are as follows:

[0076] A. System functional requirements analysis based on functional goals

[0077] According to the mission statement or technical documents of aerospace products, clarify the functional requirements of the product, including the following aspects:

[0078] Product usage scenarios (such as specific environments for satellites, spacecraft, etc.)

[0079] Mission requirements (such as payload function, attitude control accuracy, etc.)

[0080] Technical objectives (such as temperature range, radiation resistance, life cycle, etc.)

[0081] Through the analysis of the system's functional requirements, the key performance parameters of aerospace products are determined, such as thermal stability, vibration resistance, and anti-electromagnetic interference capability.

[0082] B. Collect relevant test information of the product

[0083] According to the determined performance parameters, collect relevant test information of the product, including:

[0084] Test points: test points of key components or functional modules, such as control systems, thermal management systems, etc.

[0085] Test items: Test items for each test point, such as temperature tolerance test, vibration test, radiation test, etc.

[0086] Test plan: includes specific test steps, test environment requirements and test instruments.

[0087] Fault sample set: Record the historical fault information of related products to form a fault sample set for reference and comparison in subsequent testing.

[0088] C. Relationship between quantitative analysis performance parameters and test information

[0089] Based on the collected test information, quantitative analysis is performed to determine the correlation between performance parameters and each test item. For example:

[0090] Verify thermal stability through temperature testing;

[0091] Verify vibration resistance through vibration testing;

[0092] The anti-interference performance is verified through electromagnetic interference testing.

[0093] During the analysis process, for each performance parameter, the test coverage in each test item is calculated. Test coverage refers to the coverage ratio of the performance parameter under different test conditions, such as whether the temperature test range covers the temperature extremes that may be encountered in the actual working environment of the product.

[0094] D. Classification of unmeasurable parameters

[0095] During the quantitative analysis process, some performance parameters cannot be verified by direct testing. Therefore, this embodiment classifies these unmeasurable parameters:

[0096] Category I unmeasurable parameters: These parameters cannot be directly tested due to technical limitations or unavailability of test equipment. For example, some performance related to long-term exposure in space (such as the long-term irradiation effect of materials) may not be achieved in ground simulation tests.

[0097] Category II unmeasurable parameters: These parameters can only be measured after the lower-level product has been tested. For example, local testing of some subsystems can only be performed after the subsystem integration is completed.

[0098] Category III unmeasurable parameters: These parameters can only be tested after the upper-level product (i.e., system integration is completed). For example, some system-level performance targets (such as overall attitude control capability) must be verified after the entire spacecraft is completed.

[0099] E. Determine the second-tier user needs

[0100] The unmeasurable parameters of category I, category II and category III are taken as the second-level user requirements, and the importance of each parameter is determined by test coverage. Specifically:

[0101] A parameter with a high test coverage indicates that the parameter has been fully verified and is relatively less important.

[0102] Parameters with low test coverage indicate that the degree of verification is insufficient and require enhanced follow-up testing or further monitoring after the task is completed. Such parameters are of high importance.

[0103] Through the steps of this embodiment, key performance parameters in aerospace products can be systematically identified, and parameter classification and prioritization based on test coverage can be provided for second-tier user needs, thereby ensuring that product functions meet mission requirements.

[0104] According to another embodiment of the present invention, determining the third-level user needs includes: dividing the mission phases of the aerospace product according to the aerospace product mission book or technical documents, constructing a functional framework diagram and a structural framework diagram, and generating a reliability framework diagram; performing failure mode analysis on the structure and function of the aerospace product; determining whether the failure mode is a critical type or a success-failure type; analyzing the failure mode using a fault tree analysis based on the classification of the failure mode, and identifying the root cause and hierarchical relationship of the failure; generating a list of single-point failure modes, listing all single-point failure modes that may cause the overall failure of the system; determining whether the single-point failure mode can be eliminated through redundant components or design improvement measures, and taking corresponding measures; when the result is no, identifying the design parameters related to the single-point failure mode; the design parameters identified by the single-point failure mode are used as the third-level user needs, and the failure severity obtained by analysis is used as the importance of the third-level user needs.

[0105] This embodiment determines the third-level user requirements of aerospace products by dividing the mission phase, performing failure mode analysis, and performing fault tree analysis for the mission book or technical document of the aerospace product. The specific steps are as follows:

[0106] A. Mission phase division of aerospace products

[0107] According to the mission book of aerospace products, the mission phases are usually divided into the following phases: Design phase: preliminary design, detailed design. Production phase: material procurement, component manufacturing, system integration. Testing phase: ground testing, pre-launch testing, on-orbit testing. Operation phase: normal operation, fault diagnosis, mission completion.

[0108] Construct functional framework diagrams and structural framework diagrams to clearly display the functional modules of the product and their interrelationships, and generate reliability framework diagrams to evaluate reliability requirements at different stages.

[0109] B. Failure Mode Analysis

[0110] The main steps of failure mode analysis for the structure and function of aerospace products include: identifying the potential failure modes of each functional module (such as component wear, connection failure, electronic failure, etc.) and classifying the identified failure modes to determine whether they are critical types (which may lead to catastrophic consequences for the system) or success or failure types (which may lead to mission failure but not catastrophic consequences).

[0111] C. Fault Tree Analysis

[0112] According to the classification of failure modes, apply fault tree analysis (FTA) for in-depth analysis: establish a fault tree, identify the logical relationship between failure modes, and trace the root cause and hierarchical relationship of the failure. Generate a list of single-point failure modes, listing all single-point failure modes that may cause the overall failure of the system, such as: failure of the main control unit; failure of key sensors; and failure of the power system.

[0113] D. Single point failure mode assessment

[0114] For the generated single-point failure mode, evaluate whether the single-point failure mode can be eliminated through redundant components or design improvement measures. For example, whether a backup sensor can be added or a more reliable component can be replaced. If the result is no, further identify the design parameters related to the single-point failure mode, such as: the operating temperature range of the sensor; the stability of the power system; the material strength of the structural parts.

[0115] E. Determination of third-tier user needs

[0116] The design parameters identified by the single-point failure mode are used as the third-level user requirements, and the fault severity obtained by the analysis is evaluated: Failure severity refers to the impact of the failure mode on system performance and safety after it occurs, such as the failure response time caused by the failure, the possible economic losses, etc. Design parameters with high fault severity will be considered more important, and these parameters will be given priority in design and testing to reduce potential risks.

[0117] Through the above steps, this embodiment can systematically identify key failure modes and single-point failure modes in aerospace products, and provide design parameters and priorities based on failure analysis for third-tier user needs, thereby ensuring the reliability and safety of aerospace products at all stages.

[0118] Determine overall technical goals; The overall technical objectives include a mission profile and corresponding functional and interaction objectives, wherein the mission profile is determined by the following steps: dividing the mission phases into the launch phase, the state establishment and on-orbit test phase, and the on-orbit flight phase; determining the key events of each mission phase; determining the key tasks to be done for the key events of each mission phase; determining the environment in which the aerospace product is located in each mission phase, including force, heat, and space environment; and determining the duration of each mission phase.

[0119] This embodiment aims at the overall technical goal of aerospace products, and ensures that aerospace products can meet the requirements at different mission stages by determining the mission profile and the corresponding functions and interaction goals. The specific steps are as follows:

[0120] A. Divide the task into stages

[0121] The space mission is divided into the following three main phases: Launch phase: The product is launched from the ground into the predetermined orbit. Status establishment and on-orbit testing phase: After the product enters the orbit, the status establishment and various functional tests are performed to ensure the normal operation of all subsystems. On-orbit flight phase: The product operates normally, and regular monitoring and maintenance are carried out during the mission.

[0122] B. Identify the key events for each mission stage

[0123] For each mission phase, a series of key events are identified, such as: launch phase: rocket ignition; separation of the first and second stage rockets; entering orbit.

[0124] State establishment and on-orbit testing phase: deploy solar panels; start communication systems; perform subsystem health checks.

[0125] In-orbit flight phase: orbit adjustment; data collection and transmission; orbit reduction or self-destruction operations at the end of the mission.

[0126] C. Identify key tasks

[0127] Each critical event requires specific key tasks to be performed to ensure the success of the mission. For example: Launch phase: Ensure that the rocket separates smoothly and enters the predetermined orbit. State establishment and on-orbit test phase: Check whether the communication system has established a reliable connection with the ground station. On-orbit flight phase: Regularly monitor the operating status of the product's attitude control, thermal balance and power system.

[0128] D. Determine the mission environment of aerospace products

[0129] For each mission phase, determine the specific environmental factors that aerospace products are exposed to, including:

[0130] Force environment: Launch phase: high-frequency vibration and shock; On-orbit phase: microgravity environment.

[0131] Thermal environment: Launch phase: high temperature generated during rocket launch; In-orbit phase: extreme temperature changes in space.

[0132] Space environment: Launch phase: high air density when passing through the atmosphere; In-orbit phase: vacuum environment, cosmic radiation.

[0133] E. Determine the duration of the task phase

[0134] For each mission phase, determine its scheduled duration:

[0135] Launch phase: usually lasts from a few minutes to tens of minutes. State establishment and on-orbit testing phase: may last from a few hours to a few days, depending on the complexity of the mission. On-orbit flight phase: can be from a few months to a few years, depending on the mission requirements of the aerospace product.

[0136] F. Determination of overall technical objectives

[0137] After determining the key events, key tasks, environmental conditions and duration of each mission phase, a complete mission profile is generated. The profile describes the technical requirements of each phase in detail, and annotates the functional objectives of each phase (such as communication, attitude control, data collection) and the interaction of each function (such as the coordinated work of communication and attitude control).

[0138] Through these steps, this embodiment finally determines the overall technical goals of the aerospace product, which covers the entire process of the mission, ensures that the aerospace product can complete its intended functions in different environments and has good interactive performance.

[0139] The functional objectives are determined through the following steps: constructing the requirements for system tasks and functions at each stage of the mission profile; constructing the functional requirements of the applied models; constructing the functional requirements of the models expected to be applied; and constructing a list of existing functional requirements.

[0140] The interaction targets are determined through the following steps: List the technical targets in the rows and columns of the correlation matrix to form a basic matrix framework; identify the interaction relationship between each pair of technical targets, including positive correlation, strong positive correlation, negative correlation, strong negative correlation and no correlation; fill in the corresponding relationship symbols in the cross cells of the correlation matrix to form a complete relationship matrix; analyze the constructed correlation matrix, evaluate the coordination and repeatability between the technical targets, ensure that there are no redundant technical targets, and make necessary adjustments based on the analysis results.

[0141] This embodiment provides a specific method for determining the functional objectives and interaction objectives of aerospace products, covering the entire process from the construction of mission profiles to the analysis of the technical objective correlation matrix.

[0142] 1. Steps to determine functional objectives

[0143] Construct the requirements for system tasks and functions at each stage of the mission profile

[0144] First, according to the profile of the space mission, determine the requirements for system tasks and functions in each mission phase. For example: Launch phase: The system needs to have anti-vibration, anti-shock and stable attitude control functions. In-orbit test phase: The product needs to have the ability to deploy solar panels, conduct communication system tests and subsystem function self-tests. In-orbit flight phase: Continuous power supply, attitude control, data transmission and normal operation of mission equipment are required.

[0145] Building functional requirements for applied models

[0146] Refer to the aerospace product models that have been successfully applied and build a functional requirement list for the model. For example, the functions of an applied model include: attitude control system (ACS); power management system (EPS); communication subsystem; data collection and storage system.

[0147] Functional requirements of the intended application model

[0148] According to future mission requirements, the functional requirements of the expected application model are constructed, and corresponding functional expansion is proposed in combination with the technology development trend. For example: adding autonomous fault detection and repair functions; improving the efficiency of the power management system; and enhancing the data transmission rate.

[0149] Build a list of existing feature requests

[0150] The requirements of each stage of the mission profile, the functional requirements of the applied models and the functional requirements of the expected application models are integrated to form an existing functional requirements list. This list lists the core functions of all aerospace products and provides a basis for subsequent interaction analysis.

[0151] 2. Steps to determine the interaction target

[0152] Building a basic matrix framework

[0153] The functional objectives are listed as technical objectives in the rows and columns of the correlation matrix to form a basic matrix framework. Each unit in the matrix represents the interaction between one functional objective and another functional objective.

[0154] Identify interactions between technical objectives

[0155] Analyze each pair of technical goals and identify the interactions between them. Specifically, they include the following categories: Positive correlation: The two goals promote each other, such as attitude control system and power management system. Strong positive correlation: The synergy between the two goals is extremely significant, such as communication system and data transmission system. Negative correlation: The two goals restrict each other, such as a higher-power propulsion system may increase the load on the power system. Strong negative correlation: The conflict between the two goals seriously affects the system performance. Uncorrelated: There is no obvious interaction between the two goals.

[0156] Fill in the corresponding relationship symbol

[0157] In the cross cells of the correlation matrix, fill in the above relationship symbols. For example:

[0158] There is a positive correlation between the attitude control system (ACS) and the power management system (EPS), fill in "+". There may be a negative correlation between the propulsion system and the power management system, fill in "-". Fill in "0" between targets that do not interact.

[0159] Analyze the correlation matrix by analyzing the constructed correlation matrix to evaluate the coordination and duplication between technical goals. Pay special attention to the areas of strong negative correlation and no correlation to ensure that there are no conflicting design parameters or redundant functional requirements.

[0160] Make necessary adjustments Based on the analysis results of the correlation matrix, make necessary adjustments to the technical objectives. For example, optimize the design of systems with negative or strong negative correlations to reduce unnecessary system conflicts. Delete redundant technical objectives to ensure the simplicity and efficiency of system design.

[0161] Finally, the functional objectives and interaction objectives of aerospace products were determined through the above steps. Through the correlation matrix analysis, the rational design of aerospace product functions was achieved, ensuring the efficient collaboration and performance optimization of each sub-function of the system, providing a solid technical guarantee for the successful execution of aerospace missions.

[0162] Determine the key overall technical objectives of the system-level product based on the user needs and the overall technical objectives. Standard .

[0163] Determine the best overall technical goal (best TM) and the worst overall technical goal (worst TM) for each of the user requirements (CR); specify the priority of the best TM relative to other overall technical goals (other TMs), use a numerical range of 1 to 9 to represent the importance of the best TM relative to other TMs, and generate a priority vector from the best to other overall technical goals for comparison; specify the priority of other TMs relative to the worst TM, use a numerical range of 1 to 9 to represent the importance of other TMs relative to the worst TM, and generate a priority vector from other overall technical goals to the worst overall technical goals for comparison; establish an optimization model based on the priority vector to optimize the weight distribution of the overall technical goals; determine the weight of the overall technical goal under each of the user requirements (CR) by solving the optimization model; verify the accuracy of the weight distribution, and when the weight distribution is accurate, use the weight distribution result of the overall technical goal as the basis for key overall technical goal decision-making.

[0164] An optimization model is established based on the priority vectors to determine the weight of the overall technical goal under each of the user requirements (CR), including: applying the priority vectors from the best overall technical goals for comparison to other overall technical goals and the priority vectors from other overall technical goals for comparison to the worst overall technical goals to the following model:

[0165]

[0166] w B is the weight of the optimal overall technical goal, w W is the weight of the worst overall technical goal, w j is the weight of other overall technical goals, a Bjis the comparison result of the best overall technical goal relative to other overall technical goals, a wj is the comparison result of other overall technical objectives relative to the worst overall technical objective; solve the above model to minimize the differences in all pairwise comparisons to determine the optimal weight of each overall technical objective.

[0167] Quality Function Deployment is used to convert user requirements into design specifications in the product concept design phase. A design relationship matrix can be used to map different requirements for product solutions. In traditional methods, the way weights in the relationship matrix are determined may lead to deviations in the ranking of technical measures. Although some methods such as the Analytical Hierarchy Process (AHP) have been proposed to improve this problem, they require additional data collection and processing. This patent determines a method for determining the weights of technical measures in a relationship matrix. This method not only reduces data collection, but also improves the inconsistency problem. Compared with existing methods, the efficiency and accuracy of the technical measure weight solution are improved.

[0168] This patent invents a method for assigning weights in the relationship matrix between user needs and overall technical goals. The important task of assigning weights is to determine the relationship between user needs and overall technical goals. The input for determining the weight of the overall technical goal is user needs, and the output is the final weight of each overall technical goal. The detailed steps are as follows:

[0169] Based on benchmarks of existing designs or the designer’s knowledge, define the overall technical goals that will have the greatest impact on user needs and product performance.

[0170] Identify the best (most important) and worst (least important) overall technical goals associated with each user need.

[0171] Assign the priority of the best overall technical goal relative to other overall technical goals. Use a numeric range from 1 to 9 to indicate the importance of the best overall technical goal relative to other overall technical goals. The output of this step is a priority vector of the best to other overall technical goals. B =(a B1 , a B2 , a Bj ..., a Bn ), where a Bj Indicates the priority of the best overall technical goal relative to other overall technical goals.

[0172] Specify the priority of all overall technical goals relative to the worst overall technical goal. Use a numerical range of 1 to 9 to indicate the importance of other overall technical goals relative to the worst overall technical goal. The output of this step is a priority vector of other overall technical goals to the worst overall technical goal. W =(a W1 , aW2 , ..., a Wn ), a wj Indicates the priority of all overall technical goals relative to the worst overall technical goal.

[0173] Find the optimal w for each user requirement in the relationship matrix j For each user requirement, identify a set of related overall technical goals. Determine the relationship between the overall technical goals and user requirements by using the data from the priority vector of the best to other overall technical goals and the priority vector of other overall technical goals to the worst overall technical goals. For each overall technical goal, use the following optimization problem to find the optimal r value based on the relationship between the best overall technical goal and the worst overall technical goal:

[0174]

[0175] By solving this optimization problem, we can find the optimal weight of each overall technical goal relative to user needs and obtain w in the relationship matrix. j value.

[0176] Verify the accuracy of weight distribution, including: (1) Determine equation a Bj ×a wj =a BW Is it true, where a BW is the comparison result of the best overall technical goal relative to the worst overall technical goal; (2) If the above conditions are not met, the correction parameter ξ is used to adjust; (a Bj -ξ)×(a Wj -ξ)=a BW +ξ, judge whether the result of ξ\CI meets the preset threshold, where the threshold is defined as 0.1; if any one of (1) or (2) is met, the weight distribution is defined as accurate.

[0177] Different BW The consistency index (CI) of the values ​​is defined as follows:

[0178] <![CDATA[a BW ]]> 1 2 3 4 5 6 7 8 9 CI 0 0.4 1 1.6 2.3 3 3.7 4.4 5.2

[0179] when a Bj ×a wj =a BW When the comparison is completely consistent, a Bj is the priority of the best overall technical goal relative to the overall technical goal, a wj is the priority of the overall technical goal relative to the worst overall technical goal, a BW is the priority of the best overall technical goal relative to the worst overall technical goal. If this condition is not met, a correction parameter ξ is used to adjust: (aBj -ξ)×(a Wj -ξ)=a BW +ξ.

[0180] For example, after collecting the necessary data and solving the optimization problem, the weight values ​​of the following relationship matrix are obtained. Taking the "lightweight" requirement as an example, the final weight values ​​of the relevant overall technical goals are: w TM1 =0.35, w TM5 =0.101, w TM7 =0.109, w TM11 =0.046, w TM12 =0.169, w TM14 =0.062, w TM15 =0.16. In this case, the ratio of the best overall technical goal to the worst overall technical goal is a BW =9, the consistency index calculated by the above method is 5.2. The calculated consistency ratio is: 0.046 / 5.22=0.008.

[0181] This result shows that the pairwise comparison has a high accuracy. This comparison structure provides a simple method for decision makers to assign comparison values. By solving this optimization problem, the optimal weight of each overall technical goal relative to user needs can be found and w in the relationship matrix can be obtained. j value.

[0182] According to another embodiment of the present invention, the key overall technical goals of the system-level product are determined according to the user needs and the overall technical goals, including: sorting the overall technical goals from most important to least important according to the degree of influence of each overall technical goal on the decision-making goal; performing pairwise comparisons on the overall technical goals to generate a comparison priority vector; establishing an optimization model based on the comparison priority vector to ensure that the ratio between weight coefficients is equal to the comparison priority of the overall technical goals and satisfies mathematical transitivity conditions; solving the optimization model to determine the optimal weight of each overall technical goal while minimizing the amount of consistency deviation; and using the solved weights as the basis for decision-making on key overall technical goals.

[0183] The overall technical objectives are compared in pairs to generate a comparison priority vector, including: the comparison priority vector is β=(β 1 / 2 ,β 2 / 3 ,…,β k / (k+1) ), where β k / (k+1) Represents the priority of the kth overall technical goal relative to the k+1th overall technical goal.

[0184] Establishing an optimization model and solving the optimization model include:

[0185] Confirm that the ratio of weight coefficients is equal to the priority between the overall technical goals:

[0186]

[0187] r k represents the weight coefficient of the kth overall technical goal, r k+1 Represents the weight coefficient of the k+1th overall technical goal;

[0188] Confirm that the mathematical transitivity law is satisfied: β k / (k+1)× β (k+1) / (k+2)＝ β k / (k+2) ;

[0189] The optimal weight value of the overall technical goal is determined by minimizing φ:

[0190]

[0191] In this embodiment, firstly, the overall technical objectives are ranked from the most important to the least important according to their relevance to user needs. Then, pairwise comparison of the overall technical objectives is performed to form a comparison priority vector: β = (β 1 / 2 ,β 2 / 3 ,…,β k / (k+1) ), where β k / (k+1) Represents the priority of the kth overall technical goal relative to the k+1th overall technical goal.

[0192] Next, the optimization model is established to satisfy the following two constraints:

[0193] The ratio of the weight coefficients is equal to the priority between the TMs:

[0194]

[0195] Satisfies mathematical transitivity:

[0196] β k / (k+1)× β (k+1) / (k+2)＝ β k / (k+2) ; When these conditions are met, full consistency is achieved. The goal of the optimization model is to determine the optimal weight of the overall technical goal by minimizing the amount of deviation from full consistency φ.

[0197]

[0198] By solving the optimization problem, the optimal weight value in the relationship matrix can be obtained.

[0199] In addition to the above two methods to analyze the relationship matrix, the relationship matrix can also be determined by the following content.

[0200] Use the QFD method to transform user requirements into overall development requirements in the overall development plan, clarify the basic requirements of tactical and technical objectives, preliminarily establish relevant objectives such as model reliability, maintainability, safety, security, testability, standardization, quality, product assurance, and clarify engineering interface requirements.

[0201] (1) Determination of the importance of user needs

[0202] The quality characteristics analysis team summarizes and organizes user requirements, but these requirements are not necessarily equally important. On the other hand, there are also qualitative requirements. Therefore, it is necessary to analyze the importance of each requirement and give a weight coefficient as the importance of the requirement to quantify the qualitative problem. The hierarchical analysis method and weighted scoring method are generally used to determine the weight coefficient.

[0203] Method 1: Analytical Hierarchy Process

[0204] The analytic hierarchy process is suitable for situations where it is impossible to conduct direct surveys and research on users. Usually, there is no relevant data record and experience accumulation, so the analytic hierarchy process is considered first. In this case, the accurate determination of the importance of user demand quality requires the basic input data to have a high degree of credibility and accuracy.

[0205] Method 2: Weighted Scoring Method

[0206] The weighted scoring method is a simple and easy method widely used in engineering, but it is affected by data accuracy, operator experience and level. QFD team members determine the importance of each user requirement based on their work experience.

[0207] Importance of user needs K i (i=1, 2, ..., m) can use 1, 2, 3, 4, 5 importance levels:

[0208] 1——Requirements that do not affect the realization of functions;

[0209] 2——Requirements that do not affect the realization of main functions;

[0210] 3——Requirements that have a significant impact on the realization of functions;

[0211] 4——Important requirements that affect the realization of functions;

[0212] 5 – Basic, safety-related, and particularly important needs.

[0213] In addition, the importance of user needs can also be expressed in the form of weights, that is,

[0214] The weighted analysis method is intuitive and easy to use, while the hierarchical analysis method is more complicated but more accurate.

[0215] When the intuitive scoring method and the hierarchical analysis method are used accurately, the evaluation results of the two should be able to verify each other in terms of the relative weights of each comparison object and their proportional relationship.

[0216] Given that the importance of user needs determined by this method is highly subjective, the technical person in charge should ultimately confirm the value. For example, according to the above principles, the members of the product feature analysis team determine the importance of user needs for product installation based on their work experience and the importance scoring principles proposed in the method research, as shown in the following table.

[0217] User Need Importance (System Level Analysis Example)

[0218] Good coordination Surface roughness Structural strength Lifespan Strong environmental adaptability Good performance 3 3 3 3 3 4

[0219] (2) Establishment of relationship matrix

[0220] The rooms in the quality house represent the relationship between user needs and task objectives. The relationship matrix formed by filling in numbers at the intersection of rows and columns represents the closeness of the relationship between the two. When establishing the relationship matrix, experienced experts and scientific researchers from the development unit and related units should be invited to hold discussions and discussions many times to make the relationship between user needs and task objectives as clear as possible.

[0221] Use r ij Indicates the degree of relationship, and the quantitative evaluation criteria are as follows:

[0222] It is recommended to use relationship levels such as 1, 3, 5, 7, and 9:

[0223] 1——There is a weak relationship between the task goal and user needs corresponding to this intersection;

[0224] 3——There is a weak relationship between the task goal and user needs corresponding to this intersection;

[0225] 5——There is a general relationship between the task goal and user needs corresponding to this intersection;

[0226] 7——There is a close relationship between the task objectives and user needs corresponding to this intersection;

[0227] 9——There is a very close relationship between the task objectives and user needs corresponding to this intersection.

[0228] Depending on the actual situation, the intermediate levels of 2, 4, 6, and 8 can also be used when necessary. Sometimes the three levels of 1, 3, and 9 are also used, with ◎ representing 9, ○ representing 3, △ representing 1, and a blank representing 0, indicating that there is no relationship.

[0229] Under normal circumstances, after the relationship degree is filled into the room of the quality house, the data is irregular and the distribution is random. If the relationship degree value is abnormally distributed, it is necessary to check and modify the user needs and task objectives. Modify the relationship matrix when the following 9 abnormal situations occur:

[0230] a. Blank line. The user requirement has no corresponding task goal. In this case, the user requirement needs to be re-evaluated, or a task goal that can meet the user requirement needs needs to be added.

[0231] b. Empty column: the relationship values ​​between the task goal and all user requirements are 0. You should check which user requirement the task goal is derived from and whether it should be cancelled.

[0232] c. Rows without strong correlations indicate that the corresponding user needs are difficult to achieve, and strongly related task objectives should be extracted with the help of experts.

[0233] d. Rows with repeated correlations indicate problems in the classification of user needs. This requires checking the requirements classification tree (or affinity diagram) to determine whether some details have been properly considered. In most cases, some requirements details in the fourth layer are mixed into the third layer. If the repeated correlations make some task objectives too heavy, it will have a serious impact on product design.

[0234] e. If there are dense correlations, this may be due to problems in the hierarchical division of requirements and task objectives, which need to be rechecked and corrected. It may also be due to inappropriate determination of task objectives.

[0235] f. A row has too many relationships, indicating that the corresponding demand items are cost, reliability or safety, etc. They should be removed from the quality house and reliability, cost and safety development should be carried out specifically. The reason for these situations is that the first or second level user needs are mixed with lower level needs, and the analysis process of the demand hierarchy tree needs to be checked.

[0236] g. If a column has too many relationships, it means that the task objectives may actually be items such as cost, reliability, and safety. They should also be removed from the quality house and reliability, cost, and safety should be deployed specifically. The reason for these situations is that the first-level or second-level task objectives are mixed with lower-level task objectives. It is necessary to check the analysis process of the task objective hierarchy tree.

[0237] h. The relationship on the diagonal of the relationship matrix is ​​too simple, which means that user needs are actually task goals, just with different names. User needs should represent the voice of users, not the voice of engineering.

[0238] i. Too many weak relationships in the matrix indicate that the task objectives are not clearly developed. The task objectives should be closely related to at least one user need.

[0239] (3) Determination of the correlation matrix

[0240] Conduct an assessment of the interrelationships between task objectives, analyze the interactions between task objectives, and coordinate the various task objectives with each other without duplication. The interrelationships between task objectives can be divided into positive correlation, strong positive correlation, negative correlation, strong negative correlation, and no correlation. The following symbols are usually used to indicate the degree of correlation: a. Positive correlation ○, indicating that there is a mutually reinforcing and overlapping interaction between the two task objectives corresponding to the intersection; b. Strong positive correlation ◎, indicating that there is a strong mutually overlapping interaction between the two task objectives corresponding to the intersection; c. Negative correlation ×, indicating that there is a mutually weakening and mutually offsetting effect between the two task objectives corresponding to the intersection; d. Strong negative correlation #, indicating that the effects between the two task objectives corresponding to the intersection are strongly repulsive and have great contradictions; e. Blank indicates that there is no interaction between the two task objectives corresponding to the intersection. After the interaction between the task objectives is determined, make corresponding marks in the diamond-shaped space corresponding to the roof of the quality house.

[0241] (5) Comprehensive Assessment of the House of Quality

[0242] After the quality house is organized, it should be discussed and revised by the QFD team, and special attention should be paid to careful and thorough discussion and evaluation of the key technologies and competitiveness of the product.

[0243] The evaluation of the quality house can be based on the following principles: a. Is there a clear mismatch between the importance ranking of user requirements and the importance ranking of the task objectives that meet the requirements? b. How reliable are the data in the quality house? Do they need to be re-evaluated? c. Is the planned quality setting reasonable? d. How to deal with negatively correlated and strongly negatively correlated task objectives? Do they cause disruptive problems? e. Are the goals of the task objectives advanced and reasonable? f. Which task objectives should be transferred to the next stage of quality function deployment for in-depth analysis?

[0244] It is very useful to conduct a trade-off analysis on the quality house, especially when negative correlation and strong negative correlation appear in the correlation matrix, which indicates that there is an unfavorable interaction between the corresponding two task objectives, or they offset or contradict each other. In-depth trade-off analysis should be conducted on these two task objectives and their selection. There are two ways to deal with this. One is to refine the target user group. For the accurately positioned target user group, the quality required by them may only need one of the task objectives to meet it, or the importance of strongly negatively correlated task objectives may vary greatly, and a series of products with different focuses on task objectives can be developed accordingly. Another method is to make a comprehensive trade-off, with the goal of satisfying user needs to the greatest extent, and conduct an in-depth trade-off analysis on the contradictory task objectives in order to adjust the task objectives, weaken their interactions, or decide on the trade-off between the two user needs.

[0245] After a comprehensive assessment, the rationality of the quality house was confirmed.

[0246] (4) Determination of the importance of overall technical objectives

[0247] The relative importance of each element of the task goal to the user's needs h j for

[0248]

[0249] If the jth task goal is closely related to multiple user needs, and these user needs are important (K i larger), then h j The larger the value is, the more important the task objective is.

[0250] (5) Determination of key overall technical objectives

[0251] Quality function deployment emphasizes highlighting key points, avoids drawing a huge quality house when applying it, follows the idea of ​​the key few, and only expands the key measures that affect meeting user needs. The basic principle for determining key measures is the importance of the task goal. Generally, task goals with an importance that is 1.2 times or 1.25 times higher than the average importance of all task goals are taken as control points. According to engineering experience, although the importance of some task goals is not high enough, the technical implementation is difficult, or the current status of the technology is not satisfactory and it is believed that further improvement is needed. These task goals must also be focused on. Key measures exist in the quality house at multiple stages and can be analyzed and confirmed according to the following principles: a. Key technologies that cannot be achieved with existing technologies; b. Components with excessively high costs; c. Components that fail to pass the quality and reliability test; d. Newly developed processes and materials, etc.

[0252] After identifying the key measures, we should organize forces to tackle the problems and apply relevant engineering technologies to achieve breakthroughs in the key measures, optimize the stability of the design plans of the key measures, and resolve the technical obstacles in product development to avoid delays in the development cycle or quality risks.

[0253] The above method can be used as a general principle. For complex products, various possible situations should be considered. In this way, the key measures included are not only the measures in the basic principles, but also the following situations: a. The importance of the task goal is lower than the critical value, and the user evaluation and the company's own level are not dominant in the industry, or even lagging behind. This type of task goal needs to be taken as the object of further development and strengthened control; b. The importance of the task goal is higher than the critical value. The company's current technology can guarantee user satisfaction, but if the function realization may affect the system reliability and the realization of other functions, it should also be taken as the object of further development. It's just that the focus of subsequent work is on how to control the existing means of realization and reduce fluctuations; c. The items listed in the task goals of each stage are too costly, the quality and reliability do not meet the requirements, or are newly developed; d. If necessary, all task goals can be transferred to the next stage for development.

[0254] Identification and analysis of critical quality characteristics of subsystem-level products

[0255] In this process, the overall technical objectives are gradually decomposed into key technical objectives of subsystems. The specific analysis steps are as follows.

[0256] Establishment of aerospace product quality characteristics analysis team

[0257] The quality characteristics analysis team at this stage is mainly composed of personnel related to the subsystem or single machine, and personnel from various relevant departments such as planning management, design, process, manufacturing, equipment supply, quality management, process equipment, and military representatives (can be increased or decreased as needed). In order to more fully analyze and accurately grasp, relevant personnel of the previous level product should also participate.

[0258] Forward analysis to identify system-level critical quality characteristics that need to be decomposed and delivered

[0259] After the transformation of system-level product technical goals is completed, the resulting technical goals must be analyzed and evaluated. The principles of evaluation and analysis are as follows: (1) Whether the technical goal can be achieved in the system-level product. Goals that cannot be achieved in this level of product must be transferred to the next level for development; (2) Whether the technical goal is related to other subsystems. Goals that are related to other subsystems or products must be transferred to the next subsystem level for analysis.

[0260] Through evaluation and analysis, it is determined that the key technical objectives of the system-level product need to be further converted into subsystem-level technical objectives as the input of the analysis. If several subsystems are involved, it is necessary to establish several subsystem quality houses for analysis.

[0261] Reverse analysis, refer to the steps of system-level reverse analysis, analyze the various risks existing in the subsystem, and list the various analysis results.

[0262] Determine subsystem-level product technology goals

[0263] Analyze the mission profile and life profile of the product, draw mission profile diagrams and life profile diagrams, and clarify the composition of subsystem-level products and the corresponding functions, performance, and reliability goals.

[0264] (1) Establish life profile

[0265] The subsystem life profile is a chronological description of all events and environments experienced by the subsystem from the completion of factory testing to the end of its on-orbit life or retirement, including ground testing, storage, transportation and other links.

[0266] The life profile contains several mission profiles. A mission profile includes: a. Events / functions of a single machine during the mission phase (what the single machine does during this phase); b. Environmental conditions experienced (the worst case needs to be considered); c. Working conditions experienced, including changes in working stress, working status, and external interface characteristics (the worst case needs to be considered, and different working conditions between ground and on-orbit operation need to be considered); d. Working modes experienced (including acceptable degradation modes); e. Timing (it must be noted that the mission profile is a timing description); f. Definition of success.

[0267] The mission profile contains several environmental profiles. The environmental profile is a time-series description of the various environmental conditions that may be encountered in each event during the life cycle of a single machine. Typical environmental conditions include:

[0268] a. Original environment: including acceleration overload, vibration, shock, noise, aerodynamic force, low pressure, vacuum, high and low temperature, microgravity, geomagnetism, space charged particles, solar light pressure, ultraviolet radiation, atomic oxygen, micro-meteorites and space debris, humidity and heat and salt spray of manned and return capsules, etc. b. Introduced environment: environment introduced by design, product characteristics or internal interface of spacecraft. Including electromagnetic interference or coupling, non-metallic material outgassing, material stress corrosion, engine plume, gas and liquid discharge (or leakage) of sealed pressure vessels, stellar spin and acceleration, star-rocket structure dynamics coupling, star-ship dynamics coupling (structural flexibility, liquid sloshing) and other environments; c. Environmental effects caused by the interaction between the original environment and internal conditions: such as low-pressure corona, electrostatic discharge, cumulative effect and single particle effect of space charged particles, vacuum cold welding, contamination of (low-temperature) optical surfaces by water vapor and condensable volatiles, thermal deformation, gravity and pressure changes on components with registration accuracy requirements, etc.

[0269] Pay attention to the profiles of primary and backup units, and two or more units of the same type. The introduction environment or interaction environment generated by the unit should be analyzed as the input condition for the environmental profile analysis of other units. The unit life profile should include the profile requirements of all models that have been applied to the unit, and as much as possible include the profile requirements of all models that are expected to be applied.

[0270] (2) Analyze functional requirements

[0271] Analysis basis: a. The requirements for the tasks and functions of the single machine at each stage of the life profile of the single machine; b. The functional requirements of the applied models for the single machine; c. The functional requirements of the expected application models for the single machine; d. The list of existing functional requirements for the single machine.

[0272] Analysis output:

[0273] a. Compliance analysis results; b. Supplementary and improved functional requirements list.

[0274] (3) Analyze the main performance objectives

[0275] Analysis basis:

[0276] a. Requirements for the performance targets of a single machine at each stage of its life profile; b. Performance target requirements for a single machine by models that have been applied; c. Performance target requirements for a single machine by models that are expected to be applied; d. Existing design schemes and technical basis for a single machine, including processing equipment, process status, availability of components, etc.; e. The performance targets of some single machines are related to spacecraft orbital parameters, overall configuration, equipment layout, field of view analysis, interference analysis, response analysis, etc.; f. List of existing performance target requirements for a single machine.

[0277] Analysis output:

[0278] a. Coverage and compliance analysis results; b. Supplementary and improved performance requirements list.

[0279] (4) Analysis of usage requirements

[0280] Analysis basis:

[0281] a. The use requirements of the single machine in each stage of the life profile of the single machine; b. The use requirements of the applied models for the single machine; c. The use requirements of the models expected to be applied for the single machine; d. The existing design scheme and technical basis of the single machine; e. The list of existing use requirements for the single machine; f. Common objectives of the use requirements of the single machine.

[0282] Analysis output:

[0283] a. Coverage and compliance analysis results; b. Supplementary and improved list of usage requirements.

[0284] (5) Analyze external interfaces

[0285] Analysis basis:

[0286] a. Interface requirements for the unit in each stage of the unit life profile; b. Interface requirements for the unit by the applied models; c. Interface requirements for the unit by the expected application models; d. Existing design schemes and technical basis for the unit; e. The electromechanical and thermal interfaces of some units are related to the overall configuration of the spacecraft, equipment layout, field of view analysis, interference analysis, response analysis, etc.; f. List of existing external interfaces of the unit; g. Common targets for the external interfaces of the unit.

[0287] Analysis output:

[0288] a. Coverage, compliance and matching analysis results; b. Supplementary and improved list of external interface requirements.

[0289] (6) Analyze design constraints

[0290] Analysis basis:

[0291] a. Single-machine environmental profile; b. Model top-level specifications, such as satellite design and construction specifications, satellite reliability and safety work plan, satellite environment and reliability test specifications, satellite EMC specifications, etc.; c. Single-machine industry specifications, relevant internal specifications of the unit, etc.; d. Existing design constraints of a single machine; e. Common design constraints of a single machine.

[0292] Analysis output:

[0293] a. Envelope analysis results; b. Supplementary and improved design constraint list.

[0294] Determine subsystem-level product critical quality characteristics

[0295] Based on the above analysis results, sort out the technical goals of the product. According to the system-level steps, take the determined technical goals of the previous level product as input, and use the technical goals of the current level product as the basis for analysis, so as to identify the key technical goals of this level.

[0296] Identification and analysis of key quality characteristics of stand-alone products and components

[0297] The analysis of key quality characteristics of products should be carried out all the way to the products that can be procured. For the analysis of single-machine and component-level products, the analysis can be carried out in accordance with the analysis steps of the subsystem.

[0298] Prepare a summary table of product key quality characteristics analysis

[0299] The results of the above-mentioned analyses are filled in according to the structural levels of the products to form a summary table of key quality characteristics of the system products, as shown in the table.

[0300] Product Key Quality Characteristics List

[0301]

[0302] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for analyzing the quality characteristics of aerospace products, characterized in that: include: Translate user requirements into key overall technical goals for system-level products; Convert the key overall technical objectives into key technical objectives for subsystem-level products; Transform the key technical objectives into key objectives for single machines, components and even procureable products; Summarize the key overall technical objectives, the key technical objectives and the key objectives to form a summary table of the product quality characteristics.

2. The analysis method according to claim 1, characterized in that Translate user requirements into key overall technical goals for system-level products, including: Establishment of a team to analyze the quality characteristics of aerospace products; Identify user needs; Determine overall technical goals; Determine the key overall technical objectives of the system-level product based on the user needs and the overall technical objectives.

3. The analysis method according to claim 2, characterized in that Identify first-tier user needs, including: Classify user requirements, simplify the user requirements and define them as first-level requirements; Classify the first higher-level requirements, simplify the first higher-level requirements until the user requirements are expressed in layers, determine the final result as the first-level user requirements, and use the number of content repetitions as the importance of the first-level user requirements; Among them, the first-level user requirements meet the following conditions: the terms are concise and unambiguous; a user requirement only expresses a specific meaning; the corresponding task objectives are not regarded as user requirements; it is easy for engineering personnel to understand; user requirements at the same level are independent of each other and there is no duplication or overlap in content.

4. The analysis method according to claim 2, characterized in that Identify second-tier user needs, including: Based on the functional objectives in the aerospace product mission book or technical documents, conduct system functional requirements analysis and determine the product performance parameters; Collect relevant test information of the product, including test points, test items, test plans and failure sample sets; Quantitatively analyze the relationship between performance parameters of aerospace products and related test information, and calculate test coverage; For parameters that cannot be tested directly, they are classified as Class I unmeasurable parameters; Parameters that can only be tested on lower-level products are classified as Class II unmeasurable parameters; Parameters that can only be tested on the upper-level product are classified as Category III unmeasurable parameters; The class I unmeasurable parameters, the class II unmeasurable parameters, and the class III unmeasurable parameters are used as the second-layer user requirements, and the test coverage level is used as the importance of the second-layer user requirements.

5. The analysis method according to claim 2, characterized in that Identify third-tier user needs, including: According to the aerospace product mission book or technical documents, divide the mission phases of aerospace products, build functional framework diagrams and structural framework diagrams, and generate reliability framework diagrams; Conduct failure mode analysis on the structure and function of aerospace products; Determine whether the failure mode is of the critical type or the success-failure type; According to the classification of failure modes, apply fault tree analysis to analyze the failure modes and identify the root causes and hierarchical relationships of the failures; Generate a list of single point failure modes, listing all single point failure modes that may cause the entire system to fail; Determine whether single-point failure modes can be eliminated through redundant components or design improvements, and take appropriate measures; When the answer is no, identify the design parameters associated with the single point failure mode; The design parameters identified by the single point failure mode are used as the third-level user requirements, and the failure severity obtained by analysis is used as the importance of the third-level user requirements.

6. The analysis method according to claim 2, characterized in that The overall technical goal includes a mission profile, and corresponding functional and interaction goals, wherein the mission profile is determined by the following steps: The mission phases are divided into the launch phase, the status establishment and on-orbit test phase, and the on-orbit flight phase; Identify key events for each mission phase; Identify the key tasks that need to be done for the key events of each mission phase; Determine the environment in which aerospace products are exposed to during each mission phase, including force, heat, and space environment; Determine how long each mission phase lasts.

7. The analysis method according to claim 2, characterized in that Based on the user requirements and overall technical goals, determine the key overall technical goals of the system-level product, including: Rank the overall technical objectives from most important to least important based on the degree of impact of each overall technical objective on the user needs; Performing pairwise comparison on the overall technical objectives to generate a comparison priority vector; According to the comparison priority vector, an optimization model is established to ensure that the ratio between the weight coefficients is equal to the comparison priority of the overall technical goal and satisfies the mathematical transitivity condition; solving the optimization model to determine the optimal weight of each overall technical goal while minimizing the amount of consistency deviation; The solved weights are used as the basis for making key overall technical goal decisions.

8. The analysis method according to claim 7, characterized in that Perform pairwise comparison on the overall technical goals to generate a comparison priority vector, including: The comparison priority vector is β=(β 1 / 2 ,β 2 / 3 ,…,β k / (k+1) ) Among them, β k / (k+1) Represents the priority of the kth overall technical goal relative to the k+1th overall technical goal.

9. The analysis method according to claim 8, characterized in that Establishing an optimization model and solving the optimization model include: Confirm that the ratio of weight coefficients is equal to the priority between the overall technical goals: r k represents the weight coefficient of the kth overall technical goal, r k+1 Represents the weight coefficient of the k+1th overall technical goal; Confirm that the mathematical transitivity law is satisfied: β k / (k+1)× β (k+1) / (k+2)＝ β k / (k+2)； The optimal weight value of the overall technical goal is determined by minimizing φ:

10. The analysis method according to claim 1, characterized in that Transform the key overall technical objectives into key technical objectives for subsystem-level products, including: Establishment of a team to analyze the quality characteristics of aerospace products; Identify system-level critical quality characteristics that need to be decomposed and delivered; Determine subsystem-level product technology goals; Determine the key technical objectives of subsystem-level products based on the system-level key quality characteristics and the subsystem-level product technical objectives; convert the key technical objectives into key objectives of single machines, components and even procurable products, including: Establishment of a team to analyze the quality characteristics of aerospace products; Determine the key technical objectives of subsystem-level products that need to be decomposed and transferred; Determine the technical goals of individual machines, components and even procureable products; Based on the key technical objectives of the subsystem-level products and the key objectives of the single machines, components and parts, determine the key objectives of the single machines, components and even procureable products.

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