Reliability distribution design method and system for flexible transmission mechanism of three-coordinate measuring machine

Abstract

The invention discloses a reliability distribution design method and system for a flexible transmission mechanism of a three-coordinate measuring machine. The method comprises the following steps: determining reliability indexes of a studied subject and a whole; acquiring an initial design scheme of the flexible transmission mechanism of the three-coordinate measuring machine, and decomposing the transmission mechanism to a subsystem level; summarizing expert system suggestions to obtain expert scoring interval values of the technical level, complexity, environmental conditions, operation time, maintainability and fault loss of each subsystem, and performing aggregation processing on different expert information by using a C-POWA operator; an improved CRTIIC method is used to calculate the distribution weight of each subsystem about the reliability index, and an initial distribution result is corrected in combination with a data envelope analysis method; according to the method, the correlation among factors influencing the reliability level is considered, the reliability initial distribution result is corrected, and the rationality and accuracy of the reliability distribution result of the flexible transmission mechanism of the three-coordinate measuring machine are improved.

Description

Technical Field

[0001] This invention relates to the field of reliability design of coordinate measuring machines (CMMs), and specifically to a reliability allocation design method and system for a flexible transmission mechanism of a CMM that considers the correlation of influencing factors and the combined opinions of experts. Background Technology

[0002] Reliability allocation is a crucial step in reliability design. It is undertaken early in product development and is a process that progresses from macro to micro, from global to local, and from the whole to the details. Its core objective is to scientifically allocate the overall reliability indicators of a CNC machine tool to its various subsystems, components, or parts. This optimizes the system design, improves design quality, reduces manufacturing, usage, and maintenance costs, and ultimately lays the foundation for subsequent work, ensuring that the overall system achieves its intended reliability goals.

[0003] The reliability allocation design of the flexible transmission mechanism of a coordinate measuring machine refers to the use of comprehensive technical means and optimization strategies in the design stage to ensure that the developed transmission system can reliably achieve precise motion transmission and positioning functions under specified working conditions.

[0004] The flexible transmission mechanism of a coordinate measuring machine (CMM) is the core mechanism for achieving high-precision measurement. It possesses characteristics such as high-precision transmission, high-sensitivity response, and adaptability to complex working conditions. Its typical features include high R&D technical barriers, a high degree of customization, and small production batches. Currently, when ensuring the reliability of flexible transmission mechanisms, companies rarely adopt scientific reliability allocation design methods, instead relying more on implementing general design specifications and strengthening technical management audits to improve reliability. This traditional approach not only consumes a significant amount of time and cost but also results in low efficiency in reliability improvement due to a lack of systematic planning.

[0005] Because existing reliability allocation design techniques heavily rely on reliability data accumulated through long-term operational testing, a deep understanding of failure mechanisms is necessary for accurate parameter improvements. However, the development cost of flexible transmission mechanisms in coordinate measuring machines (CMMs) is high, and they are mostly customized or produced in small batches. Especially for new or improved transmission mechanisms, there are few market application cases, making it difficult to obtain sufficient reliability data through large-scale testing. In this situation, traditional reliability allocation methods such as fuzzy expert evaluation are needed to allocate reliability indicators. However, these methods have limitations, such as difficulty in fully and accurately expressing fuzzy information in the evaluation, easy neglect of the correlation between influencing factors, and lack of reasonable correction of reliability allocation results from an economic perspective. They also fail to meet the unique technical requirements of flexible transmission mechanisms and the actual improvement goals of enterprises, resulting in poor application effects in engineering practice.

[0006] Therefore, it is necessary to propose a new method for the reliability allocation design of the flexible transmission mechanism of a coordinate measuring machine. Summary of the Invention

[0007] Based on the background technology analysis, it is necessary to propose a reliability allocation design method and system for the flexible transmission mechanism of a coordinate measuring machine that comprehensively considers the correlation between influencing factors and integrates the fuzzy evaluation opinions of experts through common standardization.

[0008] To achieve the above-mentioned objectives, the present invention adopts the following technical solution:

[0009] A reliability allocation design method for a flexible transmission mechanism of a coordinate measuring machine includes the following steps:

[0010] S1. System-level reliability indicators are determined. Based on the user's requirements for the accuracy retention, motion stability, and life cycle of the flexible transmission mechanism of the coordinate measuring machine, and combined with the user's needs, the manufacturer's process capabilities, and industry reliability benchmark data, the overall reliability target parameters of the transmission mechanism are determined through operating condition surveys, including but not limited to mean time between failures (MTBF), failure rate (λ), and reliability R.

[0011] S2. System Hierarchical Decomposition. Obtain the initial design scheme of the flexible transmission mechanism of the coordinate measuring machine, perform functional modular decomposition on the initial design scheme of the flexible transmission mechanism, establish a hierarchical structural model including toothed belt body, pulley system, tension adjustment system, installation alignment system, protection system, motion conversion system and basic component system, clarify the functional coupling relationship between the overall flexible traditional mechanism and subsystems, and obtain the compositional relationship between different subsystems and the overall system and the correlation relationship between subsystems;

[0012] S3. Determine the set of factors and attributes that affect reliability allocation. Combining the usage characteristics and design experience of the target system, and integrating objective indicators and expert experience, construct an evaluation set of reliability influencing factors (such as: technical level, complexity, environmental conditions, operating time, maintainability, and failure loss), and use this as the evaluation index for each system. Based on the characteristics of the influencing factors, determine whether the factors affecting the reliability level of the subsystem are cost-based or benefit-based.

[0013] S4. Perform co-standard integration processing on multi-source evaluation information. An initial evaluation of the reliability influencing factors of each subsystem of the coordinate measuring machine's flexible transmission mechanism is conducted. An expert system composed of university professors, researchers from scientific research institutes, enterprise experts, and frontline workers is organized. Using the evaluation set of reliability influencing factors from step S3 as a reference, the interval number scaling method is employed to score and evaluate the reliability influencing factors of each subsystem, constructing an initial interval number evaluation matrix. Then, the C-POWA operator is used to perform co-standard integration processing on the evaluation information from different expert perspectives. Simultaneously, heterogeneous expert evaluation information is co-standardized, transforming fuzzy interval numbers into defuzzified real-valued evaluation values, forming reliability data with a unified dimension.

[0014] S5. Determine the weights of each influencing factor and perform initial allocation of reliability indicators. Based on the improved CRITIC method, process the defuzzified real-valued evaluation matrix, calculate the weights of influencing factors, and simultaneously consider the conflict and correlation of influencing factors. Integrate the defuzzified evaluation matrix and the weights of influencing factors to output the reliability influencing factor scores of each subsystem of the coordinate measuring machine's flexible transmission mechanism, taking into account the correlation of influencing factors and the combined expert opinions. Normalize the reliability influencing factor scores of each subsystem to determine the reliability allocation weight coefficients of each subsystem, and perform initial allocation of reliability indicators for the coordinate measuring machine's flexible transmission mechanism.

[0015] S6. Economic Correction and Optimization of Reliability Allocation Results: The real evaluation matrix after considering the correlation of influencing factors and the co-standard integration of expert opinions in step S4 is used as the input unit of the Data Envelopment Model (DEA). The economic loss caused by improper reliability allocation of the subsystem is used as the output unit. The reliability allocation efficiency value of each subsystem is calculated through the BCC model. A correction function containing cost constraints is constructed. The initial allocation results in step S5 are iteratively optimized to finally form a reliability allocation scheme that takes into account both technical indicators and economic rationality.

[0016] As a novel reliability allocation design method, the determination of system-level reliability indicators in step S1 includes the following steps:

[0017] Requirements gathering and analysis: Collect functional requirements documents for the flexible transmission mechanism of the coordinate measuring machine, and analyze specific information such as the measurement accuracy holding time, continuous running time, and motion stability fluctuation range of the coordinate measuring machine.

[0018] Process and benchmark research involves investigating the existing processing technology and assembly technology level of coordinate measuring machines, reviewing industry standards, technical specifications and publicly available reliability benchmark data, and determining common indicators such as mean time between failures and failure rate for similar products in the industry.

[0019] Determine the overall reliability target parameters of the transmission mechanism. Based on step 1, and combining methods such as surveys and reliability analysis, determine the allocated overall reliability indicators, such as mean time between failures (MTBF) and failure rate (λ). The relationship between the two is shown below:

[0020]

[0021] Specific indicators of reliability for allocation are determined to provide a basis for reliability allocation in steps S2 and S3.

[0022] As a novel reliability allocation design method, step S2, which involves hierarchical decomposition of the flexible transmission mechanism of a coordinate measuring machine, includes the following steps:

[0023] Design scheme analysis: In-depth analysis of the mechanical drawings, assembly drawings, control system schematic diagrams and technical parameter documents of the initial design scheme of the flexible transmission mechanism of the coordinate measuring machine, identifying the core functional modules and key components of the transmission mechanism, and clarifying the working principle and performance parameters of each component;

[0024] The functional modularization is based on the motion transmission path and functional implementation method of the transmission mechanism, dividing it into 5-10 functional modules (e.g., seven systems: toothed belt body, pulley system, tension adjustment system, installation and alignment system, protection system, motion conversion system, and basic component system). This provides a basis for experts in step S4 to evaluate the reliability of the flexible transmission mechanism of the coordinate measuring machine by allocating influencing factors.

[0025] As a new reliability allocation design scheme, step S3, which involves determining the set of factors influencing reliability allocation and their attributes, includes the following steps:

[0026] Preliminary identification of influencing factors: Analysis of the design drawings, technical documents, and operating condition data of the flexible transmission mechanism of the coordinate measuring machine (CMM) to preliminarily identify factors that may affect its reliability. An initial set of 10-20 factors is formed.

[0027] Expert screening was conducted, with a team of experts comprised of university professors, researchers from scientific research institutions, industry experts, and frontline workers. Factors with minimal impact on reliability and weak inter-factor correlations were eliminated, retaining only the core influencing factors. Let there be a total of m influencing factors, defined as a set X = {x1, x2, ..., x...}. m}

[0028] The attribute classification is determined based on the characteristics of each influencing factor's impact on reliability, categorizing them into cost-based or benefit-based factors. For cost-based factors, their values ​​are negatively correlated with the ability to improve subsystem reliability; for benefit-based factors, their values ​​are positively correlated with the ability to improve subsystem reliability. By establishing judgment rules, each factor in the evaluation set is classified, clarifying the direction of each factor's impact on reliability, and providing a basis for expert evaluation in step S4.

[0029] As a novel reliability allocation design scheme, step S4, which involves common-standard integration of multi-source evaluation information, includes the following steps:

[0030] Expert Team Formation and Training: A cross-disciplinary expert team of n people will be formed, consisting of professors in the field of mechanical reliability from universities, precision measurement experts from research institutes, chief engineers from leading industry enterprises, and front-line technicians. This team is defined as a set S = {S1, S2, ..., S...}. n Specialized training was conducted on the technical characteristics, reliability influencing factors, and interval scaling scoring rules of the flexible transmission mechanism of the coordinate measuring machine to unify the understanding of evaluation standards.

[0031] Experts were invited to score the reliability impact factors of each subsystem, resulting in a three-dimensional initial interval number evaluation matrix of n experts for m influencing factors and k subsystems. This represents the score range of the k-th expert for the j-th influencing factor of the i-th subsystem.

[0032] Initial evaluation information preprocessing involves generating a three-dimensional initial interval number evaluation matrix A from n experts on m influencing factors and k subsystems. k n×m Preprocessing:

[0033]

[0034] Where I1 represents the subscript set of benefit-type indicators, and I2 represents the subscript set of cost-type indicators.

[0035] The preprocessed evaluation matrix is ​​obtained after preprocessing.

[0036] Multi-source evaluation information is integrated using a common standard, and the C-POWA operator is applied to the preprocessed evaluation matrix. The data is integrated and processed to calculate the distance and support between different expert evaluations.

[0037]

[0038] in, These are the real-valued evaluation information of the j-th influencing factor of the i-th subsystem in the preprocessed real-valued evaluation matrices of the k-th and p-th experts, respectively.

[0039] The function F is defined as: Ω→R * satisfy: set up The corresponding numbers are: F Q ([a, b]) = μb + (1-μ)b

[0040] Therefore, we can conclude that:

[0041]

[0042] Calculate the support between different expert evaluation data:

[0043]

[0044] Ultimately, the information from two different experts can be aggregated and processed into a real-valued evaluation matrix. If the expert system consists of n experts, then the following steps are required: This process continues until the preprocessed evaluation matrices of p different experts are obtained. The evaluation matrix is ​​composed of real numbers. This provides a high-precision quantitative data foundation for subsequent reliability allocation and a calculation basis for step S5.

[0045] As a new reliability allocation design scheme, step S5, which involves determining the weights of each influencing factor, includes the following steps:

[0046] Conflict and correlation calculations are based on the defuzzified and preprocessed real-valued evaluation matrix. The system calculates the conflicts and correlations between data, and outputs reliability scores for each subsystem of the coordinate measuring machine's flexible transmission mechanism, taking into account the correlation of influencing factors and the consensus of the expert panel.

[0047] The weighting coefficients are calculated by taking the standard deviation S between the data. j Information entropy E j and conflict R j Integrated processing is performed as follows:

[0048] i represents the i-th subsystem, j represents the j-th influencing factor, k represents the k-th expert, and a represents the score.

[0049]

[0050]

[0051] C j = (1-E j +S j )R j

[0052] The real number evaluation matrix can be obtained. Weights of several influencing factors: Q j = (Q1, Q2, ..., Q m ).

[0053]

[0054] Defuzzified evaluation matrix With weight Q j The system undergoes integrated processing, outputting a reliability level score δ for each subsystem that considers the correlation of influencing factors and the consensus of the expert panel. k .

[0055] Complete the initial allocation of reliability indicators and assign reliability level scores δ to each subsystem. k Normalization processing is performed:

[0056]

[0057] The reliability allocation weight vector for each subsystem is obtained as ω = {ω1, ω2, ... ω}. p} T The reliability indicators of the flexible transmission mechanism of the coordinate measuring machine are allocated to each subsystem:

[0058] R s (R1, R2, ... R) k )≥R s *

[0059] Where R s * R represents the overall reliability index of the flexible transmission mechanism of a coordinate measuring machine. k R represents the reliability index of the k-th subsystem. s This represents the actual reliability index obtained after the system undergoes reliability allocation.

[0060] λ k =ω k ·λ

[0061]

[0062] Where ω k The weights are assigned to the k-th subsystem, and λ represents the overall failure rate of the flexible transmission mechanism of the coordinate measuring machine. k Let be the failure rate level of the k-th subsystem.

[0063]

[0064] Among them, MTBF s The mean time between failures (MTBF) for the entire flexible transmission mechanism. k Let be the mean time between failures (MTBF) of the k-th subsystem.

[0065] As a new reliability allocation design scheme, step S6, which involves economically correcting the reliability allocation result, includes the following steps:

[0066] The data envelopment analysis model is constructed by integrating the real-valued evaluation matrix after defuzzification, consideration of the correlation of influencing factors, and co-standardization of expert opinions. As the input unit of the data envelopment analysis model, the vector set Cost = (Cost1, Cost2, ..., Cost3) representing the economic losses caused by improper reliability allocation in each subsystem is used. p As the output unit, a data envelopment analysis model is constructed.

[0067] Calculate the efficiency value of the initial reliability allocation, assess the effectiveness of the data envelopment model, and output the reliability allocation efficiency value θ of each subsystem considering economic factors. k .

[0068] The reliability allocation results for the flexible transmission mechanism of the coordinate measuring machine are corrected:

[0069]

[0070] in The corrected reliability allocation index result (mean time between failures) for the kth subsystem is the final reliability allocation result for the kth subsystem.

[0071] A reliability allocation design system for a flexible transmission mechanism of a coordinate measuring machine includes:

[0072] The reliability index determination module is used to determine the overall reliability parameters of the flexible transmission mechanism of the coordinate measuring machine, including mean time between failures (MTBF), failure rate (λ), and reliability (R).

[0073] The hierarchical decomposition module is used to obtain the initial design scheme of the flexible transmission mechanism of the coordinate measuring machine, perform functional modular decomposition of the initial design scheme of the flexible transmission mechanism, clarify the functional coupling relationship between the overall flexible traditional mechanism and the subsystems, and obtain the compositional relationship between different subsystems and the overall mechanism, as well as the correlation relationship between the subsystems.

[0074] The set of influencing factors and attribute modules are determined to combine the usage characteristics and design experience of the target system, integrate objective indicators and expert experience, construct an evaluation set of reliability influencing factors, and use it as the evaluation index of the target system. Based on the characteristics of the influencing factors, the factors affecting the reliability level of the subsystem are determined to be cost-type or benefit-type.

[0075] The common standard integration module is used to perform initial evaluations of the various subsystems of the flexible transmission mechanism of the coordinate measuring machine. An expert system composed of experts from universities, enterprises, and research institutes is organized to evaluate the factor performance of each subsystem using the evaluation set of reliability influencing factors as a reference and the interval number scaling method is used to score and evaluate the factor performance of each subsystem, thus constructing an initial interval number evaluation matrix. Then, the evaluation information is common standard integrated through the continuous interval power ordered weighted average operator C-POWA to form reliability evaluation data with unified dimensions.

[0076] The module for determining the weights of influencing factors is used to process the defuzzified real-valued evaluation matrix based on the improved CRITIC objective weight calculation method for criterion-related indicators, calculate the weights of influencing factors, integrate the defuzzified evaluation matrix with the weights of influencing factors, and output the reliability influencing factor scores of each subsystem of the coordinate measuring machine's flexible transmission mechanism, taking into account the correlation of influencing factors and the joint standardization of expert groups. The reliability influencing factor scores of each subsystem are normalized to determine the reliability allocation weight coefficients of each subsystem, and the reliability index of the coordinate measuring machine's flexible transmission mechanism is initially allocated.

[0077] The correction and optimization module is used as the input unit of the data envelopment model (DEA) after taking into account the correlation of influencing factors and the common standard integration of expert opinions. It takes the economic loss caused by improper reliability allocation of subsystems as the output unit, calculates the reliability allocation efficiency value of each subsystem through the BCC model, constructs a correction function with cost constraints, iteratively optimizes the initial allocation results, and finally forms a reliability allocation scheme that takes into account both technical indicators and economic rationality.

[0078] Furthermore, the module for determining the weights of influencing factors includes:

[0079] The conflict and relevance calculation unit is used to calculate the real-valued evaluation matrix based on the information after co-standardization. The calculation of data conflicts and correlations is performed, and the output is a reliability level score of each subsystem of the coordinate measuring machine flexible transmission mechanism, taking into account the correlation of influencing factors and the consensus of the expert group.

[0080] The weighting coefficient calculation unit is used to calculate the standard deviation S between data. j Information entropy E j and conflict R j The real number evaluation matrix is ​​obtained. The weights of several influencing factors Q j The defuzzified evaluation matrix With weight Q j The system undergoes integrated processing, outputting a reliability level score δ for each subsystem that considers the correlation of influencing factors and the consensus of the expert panel. k ;

[0081] The initial allocation unit is used to complete the initial allocation of reliability indicators: assigning the reliability level score δ of each subsystem to the initial allocation unit. k After normalization, the reliability allocation weight vector ω of each subsystem is obtained. k ={ω1, ω2, ... ω p} T The reliability index of the flexible transmission mechanism of the coordinate measuring machine is allocated to each subsystem.

[0082] Furthermore, the correction and optimization module includes:

[0083] The data envelopment analysis model building unit is used to integrate the real-valued evaluation matrix after defuzzification, consideration of the correlation of influencing factors, and common standardization of expert opinions. As the input unit of the data envelopment analysis model, the vector set Cost = (Cost1, Cost2, ..., Cost) representing the economic losses caused by improper reliability allocation in each subsystem is used. p As the output unit, a data envelopment analysis model is constructed;

[0084] The efficiency value unit for calculating the initial reliability allocation is used to determine the effectiveness of the data envelopment model and output the reliability allocation efficiency value θ of each subsystem considering economic factors. k ;

[0085] The correction unit is used to correct the reliability allocation results of the flexible transmission mechanism of the coordinate measuring machine.

[0086] Compared with the prior art, the present invention has the following beneficial technical effects:

[0087] This invention considers the correlation between factors affecting reliability level and corrects the initial reliability allocation results, thereby improving the rationality and accuracy of the reliability allocation results of the flexible transmission mechanism of the coordinate measuring machine. Attached Figure Description

[0088] The invention will now be further described with reference to the accompanying drawings:

[0089] Figure 1 This is a flowchart illustrating a reliability allocation design method for a flexible transmission mechanism of a coordinate measuring machine that considers the correlation of influencing factors and the combined opinions of experts in one embodiment.

[0090] Figure 2 This is a reliability block diagram of a flexible conventional mechanism for a coordinate measuring machine in a specific embodiment;

[0091] Figure 3 This is a schematic diagram of the reliability influencing factors and their attributes selected in a reliability allocation design method for a flexible transmission mechanism of a coordinate measuring machine provided in one embodiment. Detailed Implementation

[0092] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0093] In one embodiment, Figure 1As shown, a system reliability allocation method considering the importance and difficulty of improvement of subsystems is provided, including the following steps:

[0094] S1. System-level reliability indicators are determined. Based on the accuracy retention, motion stability, and life cycle requirements of the flexible transmission mechanism of the coordinate measuring machine in this example, combined with the requirements of this example, the manufacturer's process capabilities, and industry reliability benchmark data, the overall reliability target parameters of the transmission mechanism are determined through working condition surveys. The reliability allocation index for this example is the mean time between failures (MTBF).

[0095] S2. System Hierarchical Decomposition. Obtain the initial design scheme of the flexible transmission mechanism of the coordinate measuring machine, and perform functional modular decomposition of the initial design scheme of the flexible transmission mechanism, such as... Figure 2 As shown, a hierarchical structural model is established, including the toothed belt body, pulley system, tension adjustment system, installation alignment system, protection system, motion conversion system, and basic component system, and a reliability allocation diagram is drawn.

[0096] S3. Determine the set of factors and attributes influencing reliability allocation. Based on the usage characteristics and design experience of the target system, and integrating objective indicators and expert experience, construct an evaluation set of reliability influencing factors, such as... Figure 3 As shown, the evaluation set of reliability influencing factors is determined as follows: technical level, complexity, environmental conditions, operating time, maintainability, and failure loss. Based on the characteristics of the influencing factors, the factors affecting the reliability level of the subsystem are determined to be cost-based or benefit-based.

[0097] S4. Perform co-standard integration processing on multi-source evaluation information. Initial evaluations are conducted on each subsystem of the flexible transmission mechanism of the coordinate measuring machine. An expert system composed of university professors, researchers from scientific research institutes, enterprise experts, and frontline workers is organized. Using the evaluation set of reliability influencing factors from step S3 as a reference, the interval number scaling method is employed to score and evaluate the factor performance of each subsystem, constructing an initial interval number evaluation matrix. Then, the evaluation information from different expert perspectives is co-standardized and integrated using the Continuous Interval Power Ordered Weighted Averaging Operator (C-POWA). Simultaneously, heterogeneous expert evaluation information is co-standardized, transforming fuzzy interval numbers into defuzzified real-valued evaluation values.

[0098] S5. Determine the weights of each influencing factor and perform initial allocation of reliability indicators. Based on the improved CRITIC (Criteria Importance Through Intercriteria Correlation) objective weight calculation method, process the defuzzified real-valued evaluation matrix, calculate the weights of influencing factors, integrate the defuzzified evaluation matrix with the weights of influencing factors, and output the reliability level score of each subsystem of the coordinate measuring machine flexible transmission mechanism, taking into account the correlation of influencing factors and the combined standard of expert opinions. Normalize the reliability level score of each subsystem, determine the reliability allocation weight coefficient of each subsystem, and perform initial allocation of reliability indicators for the coordinate measuring machine flexible transmission mechanism.

[0099] S6. Economic Correction and Optimization of Reliability Allocation Results: The real evaluation matrix after considering the correlation of influencing factors and the co-standard integration of expert opinions in step S4 is used as the input unit of the Data Envelopment Model (DEA). The economic loss caused by improper reliability allocation of the subsystem is used as the output unit. The reliability allocation efficiency value of each subsystem is calculated through the BCC (Banker-Charnes-Cooper Model). A correction function containing cost constraints is constructed to iteratively optimize the initial allocation results in step S5, and finally form a reliability allocation scheme that takes into account both technical indicators and economic rationality.

[0100] The Banker-Charnes-Cooper (BCC) model.

[0101] Note: The BCC model is a method in Data Envelopment Analysis (DEA). "Bank-Chains-Cooper" is the inventor of this method, which introduces the assumption of variable returns to scale on the basis of traditional data envelopment analysis.

[0102] Specifically, as a new reliability allocation design scheme for the flexible transmission mechanism of a coordinate measuring machine, the determination of the system-level reliability index in step S1 includes the following steps:

[0103] Requirements gathering and analysis: Collect functional requirements documents for the flexible transmission mechanism of the coordinate measuring machine (CMM); analyze specific requirements such as measurement accuracy retention time, continuous running time, and motion stability fluctuation range of the CMM; investigate the existing processing technology and assembly technology level of the CMM; review industry standards, technical specifications, and publicly available reliability benchmark data; determine common indicators such as average interval between failures and failure rate of similar products in the industry; and analyze the main failure modes and their impact and severity on system functions.

[0104] The final overall reliability target parameters for the transmission mechanism are determined as follows:

[0105] MTBF = 1500h

[0106] The failure rate is:

[0107]

[0108] Specifically, as a new reliability allocation design scheme for coordinate measuring machines, step S2, which involves hierarchical decomposition of the flexible transmission mechanism of the coordinate measuring machine, includes the following steps:

[0109] Design scheme analysis: In-depth analysis of the mechanical drawings, assembly drawings, control system schematic diagrams and technical parameter documents of the initial design scheme of the flexible transmission mechanism of the coordinate measuring machine, identifying the core functional modules and key components of the transmission mechanism, and clarifying the working principle and performance parameters of each component;

[0110] Based on the motion transmission path and functional implementation method of the transmission mechanism, it is divided into seven subsystems: tension adjustment system (C1), pulley system (C2), basic component system (C3), mounting and alignment system (C4), protection system (C5), toothed belt body (C6), and motion conversion system (C7). This provides a basis for experts in step S4 to evaluate the reliability allocation of the flexible transmission mechanism of the coordinate measuring machine.

[0111] Specifically, as a new reliability allocation design scheme for coordinate measuring machines, step S3, which involves determining the set of factors influencing reliability allocation and their attributes, includes the following steps:

[0112] Preliminary identification of influencing factors: Analysis of the design drawings, technical documents and operating condition data of the flexible transmission mechanism of the coordinate measuring machine to preliminarily identify factors that may affect its reliability, forming an initial set of 10-20 factors.

[0113] Through expert screening, a four-person expert team consisting of one university professor, one researcher from a research institute, one enterprise expert, and one front-line worker was organized to eliminate factors with little impact on reliability and weak correlation between factors, retaining the core influencing factors. The team selected six indicators as the set of influencing factors for subsystem reliability: technical level (T), complexity (Co), environmental conditions (E), operating time (H), maintainability (M), and failure loss (Cot).

[0114] Technical level (T), environmental conditions (E), and maintainability (M) are benefit-oriented indicators, meaning that there is a negative correlation between the technical level (T), environmental conditions (E), maintainability (M), and failure rate of the flexible transmission mechanism and its subsystems of the coordinate measuring machine. Complexity (Co), operating time (H), and failure loss (Cot) are cost-oriented indicators, meaning that there is a positive correlation between the complexity (Co), operating time (H), and failure loss (Cot), and failure rate of the flexible transmission mechanism and its subsystems of the coordinate measuring machine.

[0115] Specifically, as a new reliability allocation design scheme for the flexible transmission mechanism of a coordinate measuring machine, step S4, which involves the common-standard integration processing of multi-source evaluation information, includes the following steps:

[0116] The expert team was formed and trained by a system comprised of one university professor, one researcher from a scientific research institute, one industry expert, and one frontline worker. Specialized training was conducted on the technical characteristics of the flexible transmission mechanism of the coordinate measuring machine, the definition of reliability influencing factors, and the interval number scaling method scoring rules, to unify the understanding of evaluation standards. The interval number evaluation value rules for the six influencing factor indicators are shown in Table 1.

[0117] Table 1. Expert Evaluation Table of Factors Affecting the Reliability of Flexible Transmission Mechanism of Coordinate Measuring Machine

[0118]

[0119]

[0120] Experts were invited to score the reliability impact factors of each subsystem, resulting in four initial three-dimensional interval number evaluation matrices for the six influencing factors and seven subsystems, totaling four fuzzy evaluation matrices. Since the evaluation matrices of different experts are processed in the same way in steps S4 and S5, this example only presents the standardization, defuzzification, and realization processes for the fuzzy evaluation matrices of two experts. The initial fuzzy evaluation matrices of the two experts are shown in Table 2.

[0121] Table 2 Initial Fuzzy Evaluation Matrix of the Two Experts

[0122]

[0123] Initial evaluation information preprocessing involves applying the following formula to the two fuzzy evaluation matrices:

[0124]

[0125] This is the lower bound of the interval number evaluation performed by the k-th expert for the j-th influencing factor of the i-th subsystem. I1 represents the upper limit of the interval number evaluation performed by the k-th expert on the j-th influencing factor of the i-th subsystem; I2 represents the subscript set of benefit-type indicators and I1 represents the subscript set of cost-type indicators.

[0126] After standardization, the preprocessed evaluation matrix of the two experts is shown in Table 3:

[0127] Table 3. Evaluation matrix after standardization by the two experts.

[0128]

[0129]

[0130] Multi-source evaluation information is integrated using a common-standard method, utilizing the formula in the C-POWA operator:

[0131]

[0132] The distance and support between different expert evaluation data were calculated, and the preprocessed evaluation matrix was integrated to obtain a real number evaluation matrix as shown in Table 4.

[0133] Table 4 Real-value evaluation matrix after integrated processing

[0134]

[0135] Specifically, as a new reliability allocation design scheme for coordinate measuring machines, step S5, which involves determining the weights of each influencing factor, includes the following steps:

[0136] The weighting coefficients are calculated by taking the standard deviation S between the data. j Information entropy E j and conflict R j Calculate using the following formula:

[0137]

[0138]

[0139] C j = (1-E j +S j )R j

[0140] The weight vectors of the six influencing factors in the real-valued evaluation matrix in step S4 can be obtained as follows:

[0141] Q j =[0.18,0.16,0.16,0.16,0.17,0.16] T

[0142] The defuzzified real-valued evaluation matrix and weight vector Q from step S4 are combined. j The system performs integrated processing and outputs a vector δ of reliability level scores for each subsystem, taking into account the correlation of influencing factors and the consensus of the expert panel. k :

[0143] δ k =[06553,0.4563,0.3614,0.3700,0.3468,0.9307,0.3737] T

[0144] Complete the initial allocation of reliability indicators and assign reliability level scores δ to each subsystem. k Normalization processing is performed:

[0145]

[0146] The reliability weight vectors for each subsystem are obtained:

[0147] ω=[0.1875, 0.1306, 0.1034, 0.1059, 0.992, 0.2664, 0.1069] T

[0148] The reliability indicators of the flexible transmission mechanism of the coordinate measuring machine are allocated to each subsystem:

[0149] λ k =ω k ·λ

[0150]

[0151] The initial allocation results are shown in Table 5:

[0152] Table 5 Initial reliability allocation results of the flexible transmission mechanism of the coordinate measuring machine

[0153]

[0154]

[0155] Specifically, as a new reliability allocation design scheme for the flexible transmission mechanism of a coordinate measuring machine, the economic correction and optimization of the reliability allocation result described in step S6 includes the following steps:

[0156] The data envelopment analysis (DEA) model was constructed by using the real-valued evaluation matrix (Table 4) after defuzzification, consideration of the correlation of influencing factors, and co-standard integration of expert opinions as the input unit of the DEA model, and the vector of economic losses caused by improper reliability allocation of each subsystem, Cost = (2.3, 2.1, 1.4, 1.7, 1.4, 2.5, 1.9) (unit: 10,000 yuan), as the output unit to construct the DEA model.

[0157] Calculate the efficiency value of the initial reliability allocation, assess the effectiveness of the data envelopment model, and output the reliability allocation efficiency value θ of each subsystem considering economic factors. k As shown in Table 6:

[0158] Table 6 Initial reliability allocation efficiency values ​​for the flexible transmission mechanism of the coordinate measuring machine.

[0159]

[0160] According to data envelopment analysis theory, the closer the value of θ is to 1, the higher the efficiency of the correspondence between input and output. Therefore, the initial allocation results of the five subsystems need to be corrected.

[0161]

[0162] The final reliability distribution results of the modified flexible transmission mechanism of the coordinate measuring machine are shown in Table 7:

[0163] Table 7. Final reliability allocation results for the flexible transmission mechanism of the coordinate measuring machine (after adjustments for economic considerations).

[0164]

[0165] In summary, this method, drawing on the similarity comparison approach in reliability allocation design, comprehensively considers the correlation and conflict among factors influencing the reliability level of the flexible transmission mechanism of a coordinate measuring machine. It also incorporates the C-POWA operator to standardize and integrate fuzzy evaluation information from different experts, considers the economic losses caused by improper reliability allocation in each subsystem, uses a data envelopment analysis model to calculate the efficiency value of the initial reliability allocation, and corrects the initial reliability allocation results. This overcomes the shortcomings of traditional reliability allocation methods, such as failing to consider the correlation between factors influencing reliability levels and failing to correct reliability allocation results from an economic perspective.

[0166] This invention provides another embodiment of a reliability allocation design system for a flexible transmission mechanism of a coordinate measuring machine, comprising:

[0167] The reliability index determination module is used to determine the overall reliability parameters of the flexible transmission mechanism of the coordinate measuring machine, including mean time between failures (MTBF), failure rate (λ), and reliability (R).

[0168] The reliability index determination module includes:

[0169] Requirements Collection and Analysis Unit: Used to collect functional requirements documents for the flexible transmission mechanism of the coordinate measuring machine, and analyze the specific requirements for the measurement accuracy holding time, continuous running time, and motion stability fluctuation range of the coordinate measuring machine;

[0170] Process and Benchmark Research Unit: Used to investigate the existing processing technology and assembly technology level of coordinate measuring machines, review industry standards, technical specifications and publicly available reliability benchmark data, and determine the average interval between failures and common failure rate indicators for similar products in the industry;

[0171] Determine the overall reliability target parameters of the transmission mechanism.

[0172] The hierarchical decomposition module is used to obtain the initial design scheme of the flexible transmission mechanism of the coordinate measuring machine, perform functional modular decomposition of the initial design scheme of the flexible transmission mechanism, clarify the functional coupling relationship between the overall flexible traditional mechanism and the subsystems, and obtain the compositional relationship between different subsystems and the overall mechanism, as well as the correlation relationship between the subsystems.

[0173] The hierarchical decomposition module includes:

[0174] Design Scheme Analysis Unit: Used for in-depth analysis of the mechanical drawings, assembly drawings, control system schematic diagrams and technical parameter documents of the initial design scheme of the flexible transmission mechanism of the coordinate measuring machine, to identify the core functional modules and key components of the transmission mechanism, and to clarify the working principle and performance parameters of each component;

[0175] Functional modular division unit: Based on the motion transmission path and function implementation method of the transmission mechanism, the flexible transmission mechanism of the coordinate measuring machine is divided into 5-10 functional modules.

[0176] The set of influencing factors and attribute modules are determined to combine the usage characteristics and design experience of the target system, integrate objective indicators and expert experience, construct an evaluation set of reliability influencing factors, and use it as the evaluation index of the target system. Based on the characteristics of the influencing factors, the factors affecting the reliability level of the subsystem are determined to be cost-type or benefit-type.

[0177] The module for determining the set of influencing factors and their attributes includes:

[0178] Preliminary identification unit for influencing factors: This unit analyzes the design drawings, technical documents, and operating condition data of the flexible transmission mechanism of the coordinate measuring machine (CMM) to preliminarily identify the factors affecting the reliability of the CMM's flexible transmission mechanism and form an initial set containing 10-20 factors.

[0179] Expert experience screening unit: This unit organizes an expert team composed of university professors, researchers from scientific research institutions, industry experts, and frontline workers to eliminate factors with minor impact on reliability and weak correlation, retaining the core influencing factors. Let there be a total of m influencing factors, and define the influencing factor set X = {x1, x2, ..., x...}. m};

[0180] Attribute classification and determination unit: It is used to classify each influencing factor into cost-type or benefit-type based on the characteristics of its impact on reliability. For cost-type factors, the value of cost-type factors is negatively correlated with the ability to improve the reliability of the subsystem. For benefit-type factors, the value of benefit-type factors is positively correlated with the ability to improve the reliability of the subsystem. By establishing determination rules, each factor in the evaluation set is classified into attributes to clarify the direction of each factor's impact on reliability.

[0181] The common standard integration module is used to perform initial evaluations of the various subsystems of the flexible transmission mechanism of the coordinate measuring machine. An expert system composed of experts from universities, enterprises, and research institutes is organized to evaluate the factor performance of each subsystem using the evaluation set of reliability influencing factors as a reference and the interval number scaling method is used to score and evaluate the factor performance of each subsystem, thus constructing an initial interval number evaluation matrix. Then, the evaluation information is common standard integrated through the continuous interval power ordered weighted average operator C-POWA to form reliability evaluation data with unified dimensions.

[0182] The common standard integration module includes:

[0183] Expert Team Building and Training Unit: This unit is used to build cross-disciplinary expert teams composed of professors in the field of mechanical reliability from universities, precision measurement experts from research institutes, chief engineers from leading companies in the industry, and front-line technicians. The team is defined as a set S = {S1, S2, ..., S...}. n Based on the technical characteristics of the flexible transmission mechanism of the coordinate measuring machine, the definition of the reliability influencing factor, and the characteristics of the interval number scaling method, the evaluation rules are determined.

[0184] Experts were invited to score the reliability impact factors of each subsystem, resulting in a three-dimensional initial interval number evaluation matrix of n experts for m influencing factors and k subsystems:

[0185]

[0186] in This represents the scoring range of the i-th expert for the j-th factor of the k-th subsystem;

[0187] The initial evaluation information preprocessing unit is used to process the three-dimensional initial interval number evaluation matrix A of n experts on m influencing factors and p subsystems. k n×m Preprocessing is performed to obtain the preprocessed evaluation matrix.

[0188] The unit for co-calibrating and integrating multi-source evaluation information is used to process the preprocessed evaluation matrix using the C-POWA operator. The process involves integrating and defuzzifying the fuzzy evaluation interval information from different experts, ultimately yielding a real-valued evaluation matrix.

[0189] The module for determining the weights of influencing factors is used to process the defuzzified real-valued evaluation matrix based on the improved CRITIC objective weight calculation method for criterion-related indicators, calculate the weights of influencing factors, integrate the defuzzified evaluation matrix with the weights of influencing factors, and output the reliability influencing factor scores of each subsystem of the coordinate measuring machine's flexible transmission mechanism, taking into account the correlation of influencing factors and the joint standardization of expert groups. The reliability influencing factor scores of each subsystem are normalized to determine the reliability allocation weight coefficients of each subsystem, and the reliability index of the coordinate measuring machine's flexible transmission mechanism is initially allocated.

[0190] The module for determining the weights of influencing factors includes:

[0191] Conflict and Relevance Calculation Unit: Used to calculate real-valued evaluation matrices based on information after common-standardization. The calculation of data conflicts and correlations is performed, and the output is a reliability level score of each subsystem of the coordinate measuring machine flexible transmission mechanism, taking into account the correlation of influencing factors and the consensus of the expert group.

[0192] Weighting coefficient calculation unit: used to calculate the standard deviation S between data. j Information entropy E j and conflict R j The real number evaluation matrix is ​​obtained. The weights of several influencing factors Q j The defuzzified evaluation matrix With weight Q j The system undergoes integrated processing, outputting a reliability level score δ for each subsystem that considers the correlation of influencing factors and the consensus of the expert panel. k ;

[0193] The initial allocation unit for reliability indicators is used to assign reliability level scores δ to each subsystem. kAfter normalization, the reliability allocation weight vector ω of each subsystem is obtained. k ={ω1, ω2, ... ω p} T The reliability indicators of the flexible transmission mechanism of the coordinate measuring machine are allocated to each subsystem:

[0194]

[0195] The correction and optimization module is used as the input unit of the data envelopment model (DEA) after taking into account the correlation of influencing factors and the common standard integration of expert opinions. It takes the economic loss caused by improper reliability allocation of subsystems as the output unit, calculates the reliability allocation efficiency value of each subsystem through the BCC model, constructs a correction function with cost constraints, iteratively optimizes the initial allocation results, and finally forms a reliability allocation scheme that takes into account both technical indicators and economic rationality.

[0196] The correction and optimization modules include:

[0197] Data Envelopment Analysis (DEA) Model Building Unit: Used to integrate the defuzzified, factor-considered, and expert-standardized real-valued evaluation matrix. As the input unit of the data envelopment analysis model, the vector set Cost = (Cost1, Cost2, ..., Cost) representing the economic losses caused by improper reliability allocation in each subsystem is used. p As the output unit, a data envelopment analysis model is constructed;

[0198] The efficiency value unit for calculating the initial reliability allocation is used to determine the effectiveness of the data envelopment model and output the reliability allocation efficiency value θ of each subsystem considering economic factors. k ;

[0199] The correction unit is used to correct the reliability allocation results of the flexible transmission mechanism of the coordinate measuring machine.

[0200]

[0201] in The corrected reliability allocation index result for the k-th subsystem is the mean time between failures (MTBF).

[0202] To keep the description concise, not all possible combinations and calculation methods of the various technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0203] The embodiments described above merely illustrate the implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims. Furthermore, any content not described in detail in this specification is prior art known to those skilled in the art.

Claims

1. A reliability allocation design method for a flexible transmission mechanism of a coordinate measuring machine, characterized in that, Includes the following steps: S1. Determination of system-level reliability indicators: Determine the overall reliability parameters of the flexible transmission mechanism of the coordinate measuring machine, including mean time between failures (MTBF), failure rate (λ), and reliability (R). S2. System Hierarchical Decomposition: Obtain the initial design scheme of the flexible transmission mechanism of the coordinate measuring machine, perform functional modular decomposition of the initial design scheme of the flexible transmission mechanism, clarify the functional coupling relationship between the overall flexible traditional mechanism and the subsystems, and obtain the compositional relationship between different subsystems and the overall mechanism, as well as the correlation relationship between the subsystems. S3. Determine the set of factors and attributes that affect reliability allocation: Combining the usage characteristics and design experience of the target system, and integrating objective indicators and expert experience, construct an evaluation set of reliability influencing factors, and use this as the evaluation index of the target system. Based on the characteristics of the influencing factors, determine whether the factors affecting the reliability level of the subsystem are cost-based or benefit-based. S4. Standardize and integrate multi-source evaluation information: Initially evaluate each subsystem of the flexible transmission mechanism of the coordinate measuring machine. Organize an expert system composed of experts from universities, enterprises and research institutes. Using the evaluation set of reliability influencing factors in step S3 as a reference, use the interval number scaling method to score and evaluate the factor performance of each subsystem, and construct an initial interval number evaluation matrix. Then, use the continuous interval power ordered weighted average operator C-POWA to standardize and integrate the evaluation information to form reliability evaluation data with unified dimensions. S5. Determine the weights of each influencing factor and perform initial allocation of reliability indicators; Based on the improved CRITIC objective weight calculation method based on criterion correlation, process the defuzzified real number evaluation matrix, calculate the weights of influencing factors, integrate the defuzzified evaluation matrix with the weights of influencing factors, output the reliability influencing factor scores of each subsystem of the coordinate measuring machine flexible transmission mechanism considering the correlation of influencing factors and the joint standardization of expert groups, normalize the reliability influencing factor scores of each subsystem, determine the reliability allocation weight coefficients of each subsystem, and perform initial allocation of reliability indicators of the coordinate measuring machine flexible transmission mechanism; S6. Economic Correction and Optimization of Reliability Allocation Results: The real evaluation matrix after considering the correlation of influencing factors and integrating expert opinions in step S4 is used as the input unit of the Data Envelopment Model (DEA). The economic loss caused by improper reliability allocation of the subsystem is used as the output unit. The reliability allocation efficiency value of each subsystem is calculated through the BCC model. A correction function containing cost constraints is constructed. The initial allocation results in step S5 are iteratively optimized to finally form a reliability allocation scheme that takes into account both technical indicators and economic rationality.

2. The reliability allocation design method for a flexible transmission mechanism of a coordinate measuring machine according to claim 1, characterized in that, The determination of system-level reliability indicators in step S1 includes the following steps: Requirements gathering and analysis: Collect functional requirements documents for the flexible transmission mechanism of the coordinate measuring machine, and analyze the specific requirements for the measurement accuracy holding time, continuous running time, and motion stability fluctuation range of the coordinate measuring machine; Process and benchmark research: Investigate the existing processing technology and assembly technology level of coordinate measuring machines, review industry standards, technical specifications and publicly available reliability benchmark data, and determine the average interval between failures and common failure rate indicators for similar products in the industry; Determine the overall reliability target parameters for the transmission mechanism.

3. The reliability allocation design method for a flexible transmission mechanism of a coordinate measuring machine according to claim 2, characterized in that, The system hierarchical decomposition described in step S2 includes the following steps: Design Scheme Analysis: In-depth analysis of the mechanical drawings, assembly drawings, control system schematic diagrams and technical parameter documents of the initial design scheme of the flexible transmission mechanism of the coordinate measuring machine, identifying the core functional modules and key components of the transmission mechanism, and clarifying the working principle and performance parameters of each component; Functional modular division: Based on the motion transmission path and function implementation method of the transmission mechanism, the flexible transmission mechanism of the coordinate measuring machine is divided into 5-10 functional modules.

4. The reliability allocation design method for a flexible transmission mechanism of a coordinate measuring machine according to claim 2, characterized in that, Step S3, which involves determining the set of factors and attributes influencing reliability allocation, includes the following steps: Preliminary identification of influencing factors: Analysis of the design drawings, technical documents, and operating condition data of the flexible transmission mechanism of the coordinate measuring machine (CMM) was conducted to preliminarily identify the factors affecting the reliability of the flexible transmission mechanism of the CMM; an initial set of 10-20 factors was formed. Expert experience screening: An expert team composed of university professors, researchers from scientific research institutions, industry experts, and front-line workers was organized to eliminate factors with minor impact on reliability and weak correlation, retaining the core influencing factors. Let there be a total of m influencing factors, and define the set of influencing factors X = {x1, x2, ..., x...} m }; Attribute classification and determination: Based on the impact characteristics of each influencing factor on reliability, each influencing factor is divided into cost-type or benefit-type. For cost-type factors, the value of cost-type factors is negatively correlated with the ability to improve the reliability of the subsystem. For benefit-type factors, the value of benefit-type factors is positively correlated with the ability to improve the reliability of the subsystem. By establishing judgment rules, each factor in the evaluation set is classified into attributes to clarify the direction of each factor's impact on reliability.

5. The reliability allocation design method for a flexible transmission mechanism of a coordinate measuring machine according to claim 4, characterized in that, The steps for co-standard integration of multi-source evaluation information described in step S4 are as follows: Expert Team Building and Training: A cross-disciplinary expert team will be established, consisting of professors from universities specializing in mechanical reliability, precision measurement experts from research institutes, chief engineers from leading industry enterprises, and frontline technicians. This team will be defined as a set S = {S1, S2, ..., S...}. n Based on the technical characteristics of the flexible transmission mechanism of the coordinate measuring machine, the definition of the reliability influencing factor, and the characteristics of the interval number scaling method, the evaluation rules are determined. Experts were invited to score the reliability impact factors of each subsystem, resulting in a three-dimensional initial interval number evaluation matrix of n experts for m influencing factors and k subsystems: in This represents the scoring range of the i-th expert for the j-th factor of the k-th subsystem; Initial evaluation information preprocessing involves generating a three-dimensional initial interval number evaluation matrix A from n experts on m influencing factors and p subsystems. k n×m Preprocessing is performed to obtain the preprocessed evaluation matrix. Multi-source evaluation information is integrated using a common standard, and the C-POWA operator is applied to the preprocessed evaluation matrix. The process involves integrating and defuzzifying the fuzzy evaluation interval information from different experts, ultimately yielding a real-valued evaluation matrix.

6. The reliability allocation design method for a flexible transmission mechanism of a coordinate measuring machine according to claim 5, characterized in that, The steps for determining the weights of each influencing factor described in step S5 are as follows: Conflict and Relevance Calculation: Based on the Real-Number Evaluation Matrix After Information Co-calibration The calculation of data conflicts and correlations is performed, and the output is a reliability level score of each subsystem of the coordinate measuring machine flexible transmission mechanism, taking into account the correlation of influencing factors and the consensus of the expert group. Weighting coefficient calculation: Calculate the standard deviation S between data points. j Information entropy E j and conflict R j The real number evaluation matrix is ​​obtained. The weights of several influencing factors Q j The defuzzified evaluation matrix With weight Q j The system undergoes integrated processing, outputting a reliability level score δ for each subsystem that considers the correlation of influencing factors and the consensus of the expert panel. k ; Complete the initial allocation of reliability indicators: assign reliability level scores δ to each subsystem. k After normalization, the reliability allocation weight vector ω of each subsystem is obtained. k ={ω1,ω2,…ω p } T The reliability indicators of the flexible transmission mechanism of the coordinate measuring machine are allocated to each subsystem: Among them, MTBF s The mean time between failures (MTBF) is the overall mean time between failures for the flexible transmission mechanism. k is the average fault interval time of the k-th subsystem; T represents the "transpose" in mathematical matrix / vector operations.

7. The reliability allocation design method for a flexible transmission mechanism of a coordinate measuring machine according to claim 6, characterized in that, The economic correction and optimization steps for the reliability allocation results described in step S6 are as follows: Data Envelopment Analysis Model Construction: This involves integrating the defuzzified, factor-considered, and expert-coordinated real-valued evaluation matrix. As the input unit of the data envelopment analysis model, the vector set Cost = (Cost1, Cost2, ..., Cost) representing the economic losses caused by improper reliability allocation in each subsystem is used. p As the output unit, a data envelopment analysis model is constructed; Calculate the efficiency value of the initial reliability allocation, assess the effectiveness of the data envelopment model, and output the reliability allocation efficiency value θ of each subsystem considering economic factors. k ; The reliability allocation results for the flexible transmission mechanism of the coordinate measuring machine are corrected: in is the corrected mean time between failures for the k-th subsystem.

8. A reliability allocation design system for a flexible transmission mechanism of a coordinate measuring machine, characterized in that, include: The reliability index determination module is used to determine the overall reliability parameters of the flexible transmission mechanism of the coordinate measuring machine, including mean time between failures (MTBF), failure rate (λ), and reliability (R). The hierarchical decomposition module is used to obtain the initial design scheme of the flexible transmission mechanism of the coordinate measuring machine, perform functional modular decomposition of the initial design scheme of the flexible transmission mechanism, clarify the functional coupling relationship between the overall flexible traditional mechanism and the subsystems, and obtain the compositional relationship between different subsystems and the overall mechanism, as well as the correlation relationship between the subsystems. The set of influencing factors and attribute modules are determined to combine the usage characteristics and design experience of the target system, integrate objective indicators and expert experience, construct an evaluation set of reliability influencing factors, and use it as the evaluation index of the target system. Based on the characteristics of the influencing factors, the factors affecting the reliability level of the subsystem are determined to be cost-type or benefit-type. The common standard integration module is used to perform initial evaluations of the various subsystems of the flexible transmission mechanism of the coordinate measuring machine. An expert system composed of experts from universities, enterprises, and research institutes is organized to evaluate the factor performance of each subsystem using the evaluation set of reliability influencing factors as a reference and the interval number scaling method is used to score and evaluate the factor performance of each subsystem, thus constructing an initial interval number evaluation matrix. Then, the evaluation information is common standard integrated through the continuous interval power ordered weighted average operator C-POWA to form reliability evaluation data with unified dimensions. The module for determining the weights of influencing factors is used to process the defuzzified real-valued evaluation matrix based on the improved CRITIC objective weight calculation method for criterion-related indicators, calculate the weights of influencing factors, integrate the defuzzified evaluation matrix with the weights of influencing factors, and output the reliability influencing factor scores of each subsystem of the coordinate measuring machine's flexible transmission mechanism, taking into account the correlation of influencing factors and the joint standardization of expert groups. The reliability influencing factor scores of each subsystem are normalized to determine the reliability allocation weight coefficients of each subsystem, and the reliability index of the coordinate measuring machine's flexible transmission mechanism is initially allocated. The correction and optimization module is used as the input unit of the data envelopment model (DEA) after taking into account the correlation of influencing factors and the common standard integration of expert opinions. It takes the economic loss caused by improper reliability allocation of subsystems as the output unit, calculates the reliability allocation efficiency value of each subsystem through the BCC model, constructs a correction function with cost constraints, iteratively optimizes the initial allocation results, and finally forms a reliability allocation scheme that takes into account both technical indicators and economic rationality.

9. A reliability allocation design system for a flexible transmission mechanism of a coordinate measuring machine according to claim 8, characterized in that, The module for determining the weights of influencing factors includes: The conflict and relevance calculation unit is used to calculate the real-valued evaluation matrix based on the information after co-standardization. The calculation of data conflicts and correlations is performed, and the output is a reliability level score of each subsystem of the coordinate measuring machine flexible transmission mechanism, taking into account the correlation of influencing factors and the consensus of the expert group. The weighting coefficient calculation unit is used to calculate the standard deviation s between data. j Information entropy E j and conflict R j The real number evaluation matrix is ​​obtained. The weights of several influencing factors Q j The defuzzified evaluation matrix With weight Q j The system undergoes integrated processing, outputting a reliability level score δ for each subsystem that considers the correlation of influencing factors and the consensus of the expert panel. k ; The initial allocation unit is used to complete the initial allocation of reliability indicators: assigning the reliability level score δ of each subsystem to the initial allocation unit. k After normalization, the reliability allocation weight vector ω of each subsystem is obtained. k ={ω1, ω2, ... ω p } T The reliability index of the flexible transmission mechanism of the coordinate measuring machine is allocated to each subsystem.

10. A reliability allocation design system for a flexible transmission mechanism of a coordinate measuring machine according to claim 8, characterized in that, The correction and optimization module includes: The data envelopment analysis model building unit is used to integrate the real-valued evaluation matrix after defuzzification, consideration of the correlation of influencing factors, and common standardization of expert opinions. As the input unit of the data envelopment analysis model, the vector set Cost = (Cost1, Cost2, ..., Cost) representing the economic losses caused by improper reliability allocation in each subsystem is used. p As the output unit, a data envelopment analysis model is constructed; The efficiency value unit for calculating the initial reliability allocation is used to determine the effectiveness of the data envelopment model and output the reliability allocation efficiency value θ of each subsystem considering economic factors. k ; The correction unit is used to correct the reliability allocation results of the flexible transmission mechanism of the coordinate measuring machine.

Images