Acceptance and acceptance vibration test time calculation method considering life loss

Abstract

The invention provides an acceptance vibration test time calculation method considering life loss, which relates to the technical field of environment test, and comprises the following steps: firstly, looking up the life time of a product in a product specification and the total vibration test time (durable vibration test time and functional vibration test time) corresponding to the life of the checked product; and further determining a typical mission profile of the product, calculating the vibration test time of the typical test profile according to the typical mission profile, calibrating a life loss coefficient according to the stage of the product, and finally calculating the acceptance vibration test time through a time equivalent model according to the data. According to the method, the credibility and reasonability in the acceptance vibration test process can be ensured, and product damage caused by over-test (the acceptance vibration test time is too long) can be avoided.

Description

Technical Field

[0001] The invention relates to the technical field of environmental testing, and in particular provides a method for calculating the acceptance vibration test time taking life loss into consideration. Background Art

[0002] Vibration test is one of the most common environmental test items. It is widely used in the assessment and verification of various product development, production and maintenance processes to verify whether the product can withstand the expected vibration environment. In GJB150.16A "Environmental Test Methods for Military Equipment Part 16: Vibration Test", Chapter 6 has relatively detailed provisions on the requirements for vibration test, among which the vibration test conditions mainly include vibration test profile, vibration test time, and test axis. Different test conditions correspond to different test purposes. In engineering, according to the test purpose, it mainly includes endurance vibration test, functional vibration test and acceptance vibration test. Endurance vibration test and functional vibration test time are usually used to assess the expected life index of the product. Therefore, the accelerated method is generally used for testing, and the corresponding vibration test time is usually given according to the equivalent life principle. For acceptance vibration test, it is widely used in engineering to refer to the functional vibration test profile and axis, but there is no clear provision for the test time. Even in GJB150.16A Appendix A.2 Vibration environment, the description of the duration of vibration exposure should be based on the life cycle environmental profile of the equipment is not detailed enough, and there are certain difficulties in the actual implementation process. Due to the lack of corresponding basis, the current common practice is to set the test time "on the spur of the moment". There is no distinction between the test time for different types of products and products at different stages, which often leads to over-testing and under-testing. Summary of the invention

[0003] The purpose of this application is to propose a method for calculating the acceptance vibration test time taking into account life loss, thereby avoiding over-testing or under-testing, while shortening the test time and improving the test efficiency with maximum fault excitation efficiency while ensuring that the vibration environment resistance of different products is truly assessed.

[0004] In order to achieve the above object, the present invention adopts the following technical solution: a method for calculating the acceptance vibration test time considering life loss, the method comprising:

[0005] S1: Determine the vibration test time for calibrated endurance vibration, the vibration test time for functional vibration, the corresponding life time for assessment and the typical mission profile of the product;

[0006] S2: Equivalent typical vibration environment profile duration based on typical mission profile;

[0007] S3: Calculate life loss information according to the product's full life cycle stage or reliability life index;

[0008] S4: Substitute the vibration test time of endurance vibration, the vibration test time of functional vibration, the corresponding life time of assessment, the duration of typical vibration environment profile and the life loss information into the calculation model to solve the acceptance vibration test time.

[0009] The method for calculating the acceptance vibration test time taking into account life loss provided by the present invention also has the following technical characteristics: in S1, the vibration test time for calibrated durability vibration, the vibration test time for functional vibration, the corresponding life time for assessment and the typical mission profile of the product are determined based on the overall product development requirements, technical agreements and product specifications.

[0010] The method for calculating the acceptance vibration test time taking into account life loss provided by the present invention also has the following technical feature: the time of the vibration environment experienced in the typical mission profile in S2 within the specified mission time is the duration of the typical vibration environment profile test.

[0011] The method for calculating the acceptance vibration test time considering the life loss provided by the present invention also has the following technical features: the life loss information in S3 is expressed as a life loss coefficient l n express,

[0012]

[0013] Where y is the useful life of the product.

[0014] The method for calculating the acceptance vibration test time considering life loss provided by the present invention also has such a technical feature that the calculation model in S4 is as follows:

[0015]

[0016] Where, t1 is the acceptance vibration test time, t0 is the total vibration test time of endurance vibration and functional vibration, T0 is the total life time assessed by the vibration test, T1 is the duration of the typical vibration environment profile test, l n is the life loss factor.

[0017] Beneficial Effects

[0018] The acceptance vibration test time calculation method considering life loss provided by the present invention comprehensively considers life loss and equivalent test time model, introduces life loss coefficient into the acceptance vibration test, making it have wide applicability, and further directly calculates the vibration test time based on the equivalent time model, greatly improving the credibility and effectiveness of the test. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0020] Figure 1 The present invention is a flowchart of a method provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0021] The present application is further described in detail below in conjunction with the accompanying drawings and examples, but it should be noted that these implementation methods are not limitations of the present application, and equivalent changes or substitutions in functions, methods, or structures made by ordinary technicians in the field based on these implementation methods are all within the scope of protection of the present application.

[0022] In the description of the embodiments of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the creation of the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the creation of the present application.

[0023] In addition, the terms "first", "second", "third", etc. are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the invention of this application, unless otherwise specified, the meaning of "plurality" is two or more.

[0024] The terms "installed", "connected" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the invention of this application can be understood by specific circumstances.

[0025] like Figure 1 As shown, an embodiment of the present application provides a method for calculating the acceptance vibration test time taking into account life loss, the method comprising:

[0026] S1: Determine the vibration test time for calibrated endurance vibration, the vibration test time for functional vibration, the corresponding life time for assessment and the typical mission profile of the product;

[0027] S2: Equivalent typical vibration environment profile duration based on typical mission profile;

[0028] S3: Calculate life loss information according to the product's full life cycle stage or reliability life index;

[0029] S4: Substitute the vibration test time of endurance vibration, the vibration test time of functional vibration, the corresponding life time of assessment, the duration of typical vibration environment profile and the life loss information into the calculation model to solve the acceptance vibration test time.

[0030] In the above embodiment, the typical task (use) profile refers to the time sequence description of the events and environment experienced by the product during the period of time when completing the specified task. The purpose of determining the typical task (use) profile is to obtain the duration of the product in the vibration environment profile. If the duration of the vibration environment under the typical task can be obtained through other files or methods, it can be directly adopted.

[0031] In some embodiments, S1 determines the vibration test time for calibrated endurance vibration, the vibration test time for functional vibration, the corresponding life time for assessment and the typical mission profile of the product based on the general requirements for product development, technical agreements and product specifications.

[0032] The product specifications will clearly state the environmental technical requirements for a given product or equipment. The environmental technical requirements will specify the test profiles and standards. By referring to the environmental technical requirements for vibration tests in the product specifications, you can obtain the vibration test profiles, vibration axis, and endurance / functional vibration test time. By referring to the reliability and life requirements in the product specifications, you can obtain the life time assessed by the test.

[0033] For system-level products, a development task book and general development requirements will be prepared during the development phase. The above documents will clearly state the intended use of the product and provide a typical mission profile. For subsystem-level products, the typical mission (use) profile given in the technical agreement signed between the overall unit and the subsystem will be adopted. For those not clearly stated in the technical agreement, reference can be made to the typical mission (use) profile in the development task book and general development requirements of the system-level products.

[0034] In some embodiments, the time of the vibration environment experienced in the typical mission profile in S2 within the specified mission time is the duration of the typical vibration environment profile test.

[0035] In some embodiments, the position of the product in S3 in the whole life cycle mainly includes the research and development trial production stage, the batch production delivery stage, and the repair or overhaul stage. "Reliability and life indicators" usually include but are not limited to total life and mean time between failures (MTBF). The measurement units of total life are divided into working hours (h) and calendar time (y), and MTBF is divided into the minimum acceptable value and the target value of maturity, and the measurement unit is working hours (h).

[0036] For products at different stages, the acceptance vibration test time should take into account their life loss, otherwise there will be risks of over-testing and under-testing. Taking into account the stage of the product and the reliability and life indicators, the life loss information in S3 is calculated by the life loss coefficient l n express,

[0037]

[0038] Where y is the useful life of the product.

[0039] In some embodiments, the calculation model in S4 is as follows:

[0040]

[0041] Where, t1 is the acceptance vibration test time, t0 is the total vibration test time of endurance vibration and functional vibration, T0 is the total life time assessed by the vibration test, T1 is the duration of the typical vibration environment profile test, l n is the life loss factor.

[0042] In some embodiments, a certain type of subsystem-level product is used as an example for calculation, and the specific operations are as follows:

[0043] Step 1: Check the total vibration test time and the corresponding life time of the endurance vibration and functional vibration specified in the product specifications. The endurance vibration test time is 19h, the functional vibration test time is 6h, and the MTBF is 1200h, that is, the total vibration test time and the corresponding life time are t0=19+6=25h, T0=1200h respectively.

[0044] Step 2: Determine the typical mission (use) profile of the product based on the development task book, technical agreement or general development requirements. The construction method is:

[0045] The typical mission (use) profile refers to the time-series description of the events and environment that the product experiences during the period of completing the specified mission (use). For system-level products, a development task book and general development requirements will be prepared during the development stage. The above documents will clearly state the expected use of the product and provide a typical mission profile; for subsystem-level products, the typical mission (use) profile given in the technical agreement signed between the overall unit and the product will be used. For those that are not clear in the technical agreement, the typical mission (use) profile in the development task book and general development requirements of the system-level product can be referred to. Taking a certain type of subsystem-level product as an example, according to the documents described in step 2, its typical mission profile can be determined by consulting its general development requirements.

[0046] Step 3: Equivalent the typical mission (use) profile to the duration of the typical vibration environment profile. The construction method is:

[0047] Usually, the mission (use) profile can be converted into an environmental profile, and the environmental profile can be converted into a test profile. In engineering practice, the development task book, technical agreement or general development requirements often directly give the typical mission profile and typical environmental profile. In this case, the vibration environment duration in the typical environmental profile can be directly extracted and calibrated as the vibration environment profile test duration. For the case where only the typical mission (use) profile is given, the time of the vibration environment experienced during the specified mission period in the typical mission (use) profile obtained in step 2 is intercepted and calibrated as the typical vibration environment profile test duration. Taking this type of subsystem-level product as an example, the time of the vibration environment experienced during the specified mission period in its typical mission (use) profile is 7h, that is, T1 is 7h.

[0048] Step 4: Calculate life loss information according to the product stage and reliability and life indicators. The construction method is:

[0049] From the perspective of the product's full life cycle, the acceptance vibration test time for products at different stages should take into account their life loss, otherwise there will be risks of over-testing and under-testing. For example, if a product that has been used for 10 years is assessed according to the vibration test time of a new product, it will often lead to over-testing, because part of the product's life has been consumed as the product is used. The full life cycle is divided into stages: research and development trial production stage, batch production and delivery stage, and repair or overhaul stage. Still taking this type of subsystem-level product as an example, the life loss information can be calculated using the following formula by comprehensively considering the product's stage and reliability and life indicators, that is, the life loss coefficient l n :

[0050]

[0051] Where, t1 is the acceptance vibration test time, t0 is the total vibration test time of endurance vibration and functional vibration, T0 is the total life time assessed by the vibration test, T1 is the duration of the typical vibration environment profile test, l n is the life loss coefficient. If the product is a new product in the batch production delivery stage, that is, y = 0, then l n is 1; if the product is in the repair stage and has been delivered for 1 year, that is, y = 1, then l n It is 0.8. It should be noted that the method for determining the life loss coefficient in the present invention is based on the bathtub curve calibration of the entire life cycle. This method is a recommended method. For other situations, when the quantitative life information corresponding to each stage of the product can be captured more accurately, the life loss coefficient can be calculated according to the actual situation to improve the final calculation accuracy.

[0052] Step 5: Substitute the total vibration test time, life time, typical environmental profile duration, and life loss information of endurance vibration and functional vibration into the calculation model to solve the acceptance vibration test time. The construction method is:

[0053] Substitute the total vibration test time, life time, typical environmental profile duration, and life loss coefficient of the endurance vibration and functional vibration obtained in the above steps into the calculation model to calculate the acceptance vibration test time t1:

[0054]

[0055] Where, t1 is the acceptance vibration test time, t0 is the total vibration test time of endurance vibration and functional vibration, T0 is the total life time assessed by the vibration test, T1 is the duration of the typical vibration environment profile test, l n is the life loss coefficient. Taking this type of subsystem-level product as an example,

[0056]

[0057] That is, if the product is a new product in the batch production delivery stage, that is, y=0, then the acceptance vibration test time t1 is 8.75min; if the product is a product in the repair stage and has been delivered for use for 1 year, that is, y=1, then the acceptance vibration test time t2 is 7min.

[0058] Through the above steps, the construction of the calculation method of the acceptance vibration test time based on life loss can be completed. In this technology, first, the product life time and the total vibration test time (durability vibration test time and functional vibration test time) corresponding to the product life are checked in the product specification, and then the typical task profile of the product is determined according to the top-level documents such as the development task book or the general development requirements, and then the typical test profile vibration test time is calculated according to the typical task profile, and then the life loss coefficient is calibrated according to the stage of the product, and finally the acceptance vibration test time is calculated through the time equivalent model based on the above data.

[0059] The above is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present application shall be included in the protection scope of the present application. The above is only a preferred implementation of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and variations can be made without departing from the technical principles of the present application, and these improvements and variations should also be regarded as the protection scope of the present application.

Claims

1. A method for calculating the acceptance vibration test time considering life loss, characterized in that: The method comprises: S1: Determine the vibration test time for calibrated endurance vibration, the vibration test time for functional vibration, the corresponding life time for assessment and the typical mission profile of the product; S2: Equivalent typical vibration environment profile duration based on typical mission profile; S3: Calculate life loss information according to the product's full life cycle stage or reliability life index; S4: Substitute the vibration test time of endurance vibration, the vibration test time of functional vibration, the corresponding life time of assessment, the duration of typical vibration environment profile and the life loss information into the calculation model to solve the acceptance vibration test time.

2. The method for calculating the acceptance vibration test time considering life loss according to claim 1, characterized in that: In S1, the vibration test time for calibrated endurance vibration, the vibration test time for functional vibration, the corresponding assessment life time and the typical mission profile of the product are determined based on the general requirements for product development, technical agreements and product specifications.

3. The method for calculating the acceptance vibration test time considering life loss according to claim 1, characterized in that: The time of the vibration environment experienced in the typical mission profile in S2 within the specified mission time is the duration of the typical vibration environment profile test.

4. The method for calculating the acceptance vibration test time considering life loss according to claim 1, characterized in that: The life loss information in S3 is expressed as the life loss coefficient l n express, Where y is the useful life of the product.

5. The method for calculating the acceptance vibration test time considering life loss according to claim 1, characterized in that: The calculation model in S4 is as follows: Where, t1 is the acceptance vibration test time, t0 is the total vibration test time of endurance vibration and functional vibration, T0 is the total life time assessed by the vibration test, T1 is the duration of the typical vibration environment profile test, l n is the life loss factor.

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