CN108021946B

CN108021946B - Agricultural machinery component similarity evaluation method based on system coding

Info

Publication number: CN108021946B
Application number: CN201711287252.7A
Authority: CN
Inventors: 何苗; 罗石林; 李建尧; 张成杰; 戴姚辉; 杜豪; 胡俊磊; 税云秀; 胡琳; 王伦维
Original assignee: Chongqing University of Technology
Current assignee: Chongqing University of Technology
Priority date: 2017-12-07
Filing date: 2017-12-07
Publication date: 2020-09-15
Anticipated expiration: 2037-12-07
Also published as: CN108021946A

Abstract

The invention provides an agricultural machinery component similarity evaluation method based on system coding, which is characterized in that a part coding mode aiming at the characteristics of an agricultural machinery product is formulated, and the part similarity is calculated according to the shape similarity, the part assembly similarity and the part size similarity of parts according to the topological relation of corresponding parts, so that the similarity calculation of the parts is realized, and a threshold value is set for similarity evaluation. The effectiveness and the reliability of the agricultural machine part similarity evaluation method are verified through calculation of a plurality of example models. By evaluating the similarity of the components, the components of the module library can be integrated, so that the components with more reasonable design and higher reuse degree are left, redundancy or the components with unreasonable relative design are eliminated, and the management of the components in a product platform is facilitated; more and more optimal alternatives can be provided for the configuration of the product, and the innovative design of the product is enhanced.

Description

Agricultural machinery component similarity evaluation method based on system coding

Technical Field

The invention relates to the technical field of similarity evaluation of mechanical parts, in particular to a similarity evaluation method of agricultural machinery parts based on system coding.

Background

A product family refers to a collection of similar products, each individual product in the product family having the same or similar elements or functional modules. The modular product platform is shared by a product family, and is a collection of generic, reusable modules and associated objects. In practical application, newly designed components are often added into a product platform, more and better alternatives are provided for configuration of products, innovative design of the products is enhanced, or in order to enhance universality of components in the product platform, two components with high similarity in a module library need to be compared and selected, so that more practical and reliable components are left, reuse degree of the components in the module library is improved, and redundant components are reduced.

For agricultural machinery products, the agricultural machinery products have the characteristics of multiple types, multiple shapes and multiple functions, the difference of different types of agricultural machinery is large, and most of component parts are non-standard parts. The agricultural machine parts have the characteristics of multiple types, different parts are assembled in different modes, and the similar parts also have different overall dimensions. In order to achieve better management of components of a product family in an agricultural modular product platform, similarity evaluation needs to be performed on the components of the agricultural product.

Currently, research on a product platform mainly relates to module division of a product and configuration design of the product, but research and documents for similarity evaluation of parts are relatively few.

Therefore, an agricultural machinery component similarity evaluation method which is easy to implement, high in efficiency and capable of carrying out effective comparative analysis on agricultural machinery components is needed.

Disclosure of Invention

In view of the above-mentioned shortcomings in the prior art, the present invention aims to provide a method for evaluating similarity of agricultural machinery components based on systematic codes, which can effectively evaluate similarity contrast of agricultural machinery components, and is efficient and easy to implement.

In order to achieve the purpose, the invention adopts the following technical scheme:

a method for evaluating similarity of agricultural machinery components based on system coding comprises the following steps:

A) classifying and coding different parts in different components of different agricultural products in advance, and respectively determining the classification code number of each part in each agricultural product; the classification code number of each part comprises a shape information code segment for indicating the shape characteristics of the part, an assembly information code segment for indicating the assembly mode of the part and a specification information code segment for indicating the shape specification of the part, wherein the shape information code segment, the assembly information code segment and the specification information code segment are respectively positioned at fixed code segment positions in the classification code number;

B) establishing corresponding part connection topological relation graphs aiming at different parts of different agricultural products in advance, wherein the part connection topological relation graph of each part is used for indicating the position connection relation among the parts contained in the corresponding part;

C) for two parts to be evaluated, determining topology associated part pairs contained in the two parts to be evaluated by comparing part connection topological relation graphs of the two parts to be evaluated, wherein two parts contained in each topology associated part pair respectively belong to the two parts to be evaluated, and the two parts in the topology associated part pairs have the same position connection relation in the part connection topological relation graphs of the parts to be evaluated, which the parts respectively belong to;

D) and evaluating the similarity of the two parts to be evaluated by respectively comparing the number of parts respectively contained in the two parts to be evaluated, the number of the topological related part pairs contained in the two parts to be evaluated and the similarity of the classification code numbers of the two parts in each topological related part pair.

In the method for evaluating similarity of agricultural machinery components based on system coding, as a preferred scheme, the step D) is specifically as follows:

d1) recording the two parts to be evaluated as a part A and a part B respectively, and counting the number N of parts contained in the two parts to be evaluated respectively_AAnd N_BAnd the number N of topologically related part pairs contained in the two parts to be evaluated₁And further determining the number N of parts which cannot be found in the same position connection relationship in the part A and the part B₂＝N_A-N₁And the number N of parts in the part B which cannot be found in the part A with the same positional connection relation₃＝N_B-N₁；

d2) Comparing the similarity of the classification code numbers of any ith topological related part pair contained in the part A and the part BTo determine the part similarity PS of the two parts_i；

d3) Step d2) is performed separately for each pair of topologically related parts comprised by component a and component B), determining the part similarity PS of the two parts in each pair of topologically related parts_i，i∈{1,2,…,N₁}；

d4) The similarity value US of the two parts to be evaluated is calculated as follows:

the greater the value of the resulting similarity value US, the greater the similarity of the two parts to be evaluated.

In the agricultural machinery component similarity evaluation method based on system coding, as a preferred scheme, in the classification coding number of the part, the shape information code segment for indicating the shape characteristics of the part includes shape category information code bits for indicating the shape category of the part and shape characteristic information code bits for indicating the shape differentiation characteristics of the part.

In the method for evaluating similarity of agricultural machinery components based on system coding, as a preferred scheme, the step d2) of comparing the similarity of the classification code numbers of the two parts in the pair of topology related parts includes:

determining the shape similarity TS of the two parts according to the shape information code segments in the classification code numbers of the two parts_i(ii) a If the shape type information code bit and the shape characteristic information code bit in the shape information code segment of the two parts are the same, the shape similarity TS of the two parts is judged_i1 is ═ 1; if the shape type information code bits in the shape information code segments of the two parts are the same, but the shape characteristic information code bits are different, the shape similarity TS of the two parts is judged_i0.5; if the shape type information code bit and the shape characteristic information code bit in the shape information code segment of the two parts are different, the shape similarity TS of the two parts is judged_i＝0。

In the method for evaluating the similarity of agricultural machinery components based on system coding, as a preferred scheme, in the classification coding number of the part, the assembly information code segment for indicating the assembly mode of the part includes one or more assembly mode indication code bits, and each assembly mode indication code bit is used for indicating one assembly mode of the part.

calculating the assembly similarity AS of the two parts according to the assembly information code segments in the classification code numbers of the two parts_i：

Wherein n is₁Indicating the number of the indication code bits with the same assembly mode in the assembly information code segments of the two parts in the topology associated part pair; n is₂Indicating the number of indication code bits of different assembly modes in the assembly information code segment of the first part relative to the assembly information code segment of the second part in the two parts of the topology associated part pair; n is₃And indicating the number of indication code bits of different assembly modes in the assembly information code segment of the second part relative to the assembly information code segment of the first part in two parts representing the topology associated part pair.

In the agricultural machinery component similarity evaluation method based on system coding, as a preferred scheme, in the classification coding number of the part, a specification information code segment for indicating the shape and specification of the part comprises specification model code bits for indicating the shape and specification model of the part; the parts of each shape specification model are corresponding to different size parameters, and the size parameters of the parts of each shape specification model comprise size data information of each size dimension contained in the corresponding shape specification model;

still include the size information code segment that is used for instructing part size parameter in the categorised coded number of part, size information code segment includes one or more size data code bit, and the size dimension quantity that the size data code bit number that size information code segment contained and the shape specification model of corresponding part contained is the same in the categorised coded number of part, and every size data code bit is used for recording the size data information of a size dimension that the shape specification model of its corresponding part contained.

determining the size similarity SS of the two parts according to the specification information code segment, the assembly information code segment and the size information code segment in the classification code numbers of the two parts_i；

If the specification information code segments of the two parts are the same, the assembly information code segments of the two parts are also completely the same, and the size data information of the corresponding size dimension in the size information codes of the two parts is also the same, the size similarity SS of the two parts is judged_i＝1；

If the specification information code segments of the two parts are the same, the assembly information code segments of the two parts are also completely the same, but the size data information of the corresponding size dimensions in the size information codes of the two parts is not completely the same or different, and the difference of the different size data values of the size dimensions is less than or equal to 10%, then the size similarity SS of the two parts is judged_i＝0.8；

If the specification information code segments of the two parts are the same, the assembly information code segments of the two parts are also completely the same, but the size data information of corresponding size dimensions in the size information codes of the two parts is not completely the same or different, the difference of different size data values of at least one size dimension is more than 10%, but the difference of different size data values of each size dimension is less than or equal to 20%, then the size similarity SS of the two parts is judged_i＝0.7；

If the specification information code segments of the two are the same, but the assembly information code segments of the two are the same, all the assembly information code segments of one part are the same as part of the assembly information code segments of the other part, and the size data information of corresponding size dimensions in the size information codes of the two are not completely the same or are all the sameDifferent, and the difference of different size data values of all size dimensions is less than or equal to 10%, then the size similarity SS of the two parts is judged_i＝0.6；

If the specification information code segments of the two parts are the same, but in the assembly information code segments of the two parts, all the assembly information code segments of one part are the same as part of the assembly information code segments of the other part, the size data information of corresponding size dimensions in the size information codes of the two parts are not completely the same or different, the difference of different size data values of at least one size dimension is more than 10%, but the difference of different size data values of each size dimension is less than or equal to 20%, then the size similarity SS of the two parts is judged_i＝0.5；

If the specification information code segments of the two parts are the same, but the assembly information code segments of the two parts are different from each other, the size data information of corresponding size dimensions in the size information codes of the two parts are also different from each other or different from each other, and the difference of different size data values of the size dimensions is less than or equal to 10%, the size similarity SS of the two parts is judged_i＝0.3；

If the specification information code segments of the two parts are the same, but the assembly information code segments of the two parts are different from each other, the size data information of corresponding size dimensions in the size information codes of the two parts are also different from each other or different from each other, the difference of different size data values of at least one size dimension is more than 10%, but the difference of different size data values of all size dimensions is less than or equal to 20%, then the size similarity SS of the two parts is judged_i＝0.2；

If the specification information code segments of the two parts are the same, but the assembly information code segments of the two parts are completely different, or the difference of different size data values of at least one size dimension in the size information codes of the two parts is more than 20%, judging the size similarity SS of the two parts_i＝0.1；

If the specification information code segments of the two parts are different, the size similarity SS of the two parts is judged_i＝0。

In the method for evaluating the similarity of agricultural machinery components based on system coding, the method is taken as a preferred methodIn step d2), the similarity of the classification code numbers of the two parts in the topological correlation part pair is compared, and the part similarity PS of the two parts is determined_iThe specific mode is as follows: according to the classification code numbers of the two parts, the shape similarity TS of the two parts is respectively determined_iAssembly similarity AS_iAnd the size similarity SS_i(ii) a Then, the part similarity PS of the two parts is calculated_i：

PS_i＝0.2TS_i+0.5AS_i+0.3SS_i。

Compared with the prior art, the invention has the following beneficial effects:

1. the agricultural machine component similarity evaluation method based on the system coding comprises the steps of making a part coding mode aiming at the characteristics of an agricultural machine product, judging the shape similarity, the part assembly similarity and the part size similarity of parts according to the topological relation of corresponding parts, calculating the part similarity, further realizing the similarity calculation of the parts, and setting a threshold value for evaluating the similarity.

2. In the agricultural machinery component similarity evaluation method based on the system coding, the multi-dimensional component similarity calculation is carried out on the basis of the aspect that the quantity, the shape, the assembly mode, the specification size and the like of the components have influence on the similarity of the components, so that the evaluation on the similarity of the components is realized, and the objectivity and the accuracy of the evaluation on the similarity of the components are better ensured.

3. The coding mode of the part classification coding number formulated in the method can also provide a basis for the classification management of the part drawing in the system and the regular and ordered management of the whole system, and is more favorable for the classification management of the parts and the parts formed by the parts.

Drawings

FIG. 1 is a flow chart of the method for evaluating similarity of agricultural machinery components based on system coding according to the present invention.

FIG. 2 is an exemplary illustration of part classification code numbers of an agricultural product according to an embodiment.

FIG. 3 is a comparative illustration of the part connection topology of two components in the embodiment.

FIG. 4 is a diagram illustrating the shape classification and the set relationship of shape differentiation features of a part.

Fig. 5 is a three-dimensional simulation diagram of the structure of the first armrest frame member in the calculation example.

Fig. 6 is an exploded view of the structure of a first type of armrest frame member in the calculation example.

Fig. 7 is a structural three-dimensional simulation diagram of a second armrest frame member in the calculation example.

Fig. 8 is an exploded view of the structure of a second armrest frame member in the calculation example.

Fig. 9 is a three-dimensional simulation diagram of the structure of a third handrail frame member in the calculation example.

Fig. 10 is an exploded view of the structure of a third armrest frame member in the calculation example.

Fig. 11 is a three-dimensional simulation diagram of the structure of a fourth handrail frame member in the calculation example.

Fig. 12 is an exploded view of the structure of a fourth armrest frame member in the calculation example.

Detailed Description

The invention provides an agricultural machinery component similarity evaluation method based on system coding, the specific flow of the evaluation method is shown in figure 1, and the method comprises the following steps:

A) classifying and coding different parts in different components of different agricultural products in advance, and respectively determining the classification code number of each part in each agricultural product; the classification code number of each part comprises a shape information code segment for indicating the shape characteristics of the part, an assembly information code segment for indicating the assembly mode of the part and a specification information code segment for indicating the shape specification of the part, wherein the shape information code segment, the assembly information code segment and the specification information code segment are respectively at the positions of fixed code segments in the classification code number.

In agricultural products, the similarity of components is considered, and the problem of part similarity of component components is considered firstly. Considering the problem of similarity of parts, a coding mode for the part characteristics of agricultural machinery products needs to be established, and classification coding is carried out on the agricultural machinery parts through a corresponding coding table so as to determine the classification coding numbers of the parts. And then, analyzing the position connection relation of the parts of the two agricultural machinery components needing similarity calculation, and judging the similarity of the parts according to the classification code numbers of the parts of the two components with the corresponding position connection relation. And finally, according to the similarity result of the parts, performing similarity calculation and similarity evaluation on the parts. Based on the idea, classification and coding are required to be performed on different parts in different components of different agricultural products in advance, and the classification and coding number of each part in each agricultural product is determined respectively.

Agricultural machinery products have multiple types, multiple shapes and multiple functions, different types of agricultural machinery are greatly different, and most of component parts are non-standard parts. The agricultural machine parts have the characteristics of multiple types and different part assembling modes, even the same type of parts can have different shape specifications, therefore, the similarity of the parts is judged based on the classification code number of the parts, the classification code number of each part at least comprises a shape information code segment for indicating the shape characteristics of the parts, an assembling information code segment for indicating the part assembling mode and a specification information code segment for indicating the part shape specification, so that the part similarity can be accurately distinguished, and the shape information code segment, the assembling information code segment and the specification information code segment are respectively positioned at fixed code segment positions in the classification code number, so as to facilitate code segment identification and similarity analysis processing. In addition, considering that the agricultural machinery product has the characteristics of multiple types and multiple functions, if the difference of the similarity of the parts is more abundant through the classification code number of the parts, the classification code number of the parts can also be designed to comprise other part characteristic information code segments such as an agricultural machinery category code segment for indicating the style of the agricultural machinery product, a function information code segment for indicating the function type of the part to which the part belongs and the like.

B) And establishing corresponding part connection topological relation graphs aiming at different parts of different agricultural products in advance, wherein the part connection topological relation graph of each part is used for indicating the position connection relation among the parts contained in the corresponding part.

In agricultural machinery products, for the similarity of components, the problem of part similarity of the components needs to be considered, and for the part similarity, a part connection topological relation needs to be established according to the position connection relation among the parts in the components, so that parts (parts with the same position connection relation) with the topological relation corresponding to each other are found in two comparison components, similarity comparison is carried out, and for parts with the topological relation not corresponding to the parts, calculation of the part similarity is not needed. Therefore, a corresponding part connection topological relation diagram needs to be established in advance for each different component of each different agricultural machine product, so as to perform comparative analysis on the part position connection relation of the two agricultural machine components.

C) For two parts to be evaluated, determining topology related part pairs contained in the two parts to be evaluated by comparing part connection topological relation graphs of the two parts to be evaluated, wherein two parts contained in each topology related part pair respectively belong to the two parts to be evaluated, and the two parts in the topology related part pairs have the same position connection relation in the part connection topological relation graphs of the parts to be evaluated, which the parts respectively belong to.

In the method of the present invention, two parts having the same position connection relationship in two parts to be evaluated have the corresponding connection topology relationship, and thus have the significance of considering the similarity of the parts, so that a topology related part pair included in the two parts to be evaluated needs to be found.

D) And evaluating the similarity of the two parts to be evaluated by respectively comparing the number of parts respectively contained in the two parts to be evaluated, the number of the topological related part pairs contained in the two parts to be evaluated and the similarity of the classification code numbers of the two parts in each topological related part pair. The specific evaluation mode of the step is as follows:

d1) recording the two parts to be evaluated as a part A and a part B respectively, and counting the number N of parts contained in the two parts to be evaluated respectively_AAnd N_BAnd the topological relations contained in the two parts to be evaluatedNumber of coupled part pairs N₁And further determining the number N of parts which cannot be found in the same position connection relationship in the part A and the part B₂＝N_A-N₁And the number N of parts in the part B which cannot be found in the part A with the same positional connection relation₃＝N_B-N₁。

d2) Aiming at two parts in any ith topological correlation part pair contained in the part A and the part B, comparing the similarity of the classification code numbers of the two parts, and determining the part similarity PS of the two parts_i。

In the idea of the method, the similarity of the parts is judged by means of the classification code numbers of the parts. Because the classification code number of each part comprises a shape information code segment for indicating the shape characteristics of the part, an assembly information code segment for indicating the assembly mode of the part and a specification information code segment for indicating the shape specification of the part, and the shape information code segment, the assembly information code segment and the specification information code segment are respectively at the fixed code segment positions in the classification code number, when the similarity of the parts is judged, the shape information code segment, the assembly information code segment and the specification information code segment which are respectively extracted from the fixed code segment positions in the classification code numbers of the two parts to be compared can be compared with each other in similarity to determine the part similarity of the two parts.

d3) Step d2) is performed separately for each pair of topologically related parts comprised by component a and component B), determining the part similarity PS of the two parts in each pair of topologically related parts_i，i∈{1,2,…,N₁}。

The present invention will be further illustrated by the following examples.

Example (b):

in this embodiment, the method for evaluating the similarity of agricultural machinery components based on system coding of the present invention is used for evaluating the similarity of agricultural machinery components, and specifically includes the following steps:

Agricultural machinery products have multiple types, multiple shapes and multiple functions, different types of agricultural machinery are greatly different, and most of component parts are non-standard parts. The agricultural machine parts have the characteristics of multiple types and different part assembling modes, the similar parts also have different external dimensions, and therefore the parts of the agricultural machine are coded and distinguished by adopting a combined coding mode of 'part type coding + variable length part assembling mode coding + specification code'. In addition, considering that the agricultural machinery product has multiple types and multiple functions, if the difference of the similarity of the parts is further embodied by the classification code number of the parts, the classification code number of the parts can also be designed to include an agricultural machinery category code segment for indicating the style of the agricultural machinery product, a function information code segment for indicating the function type of the part to which the part belongs, and other part characteristic information code segments, of course, other information code segments such as the agricultural machinery category code segment and the function information code segment can also be designed to be at the position of the fixed code segment in the classification code number, so as to be convenient for identification and extraction.

Specifically, in the classification coding number of the part, the shape information code segment for indicating the shape characteristics of the part can be designed to comprise shape class information code bits for indicating the shape class of the part and shape characteristic information code bits for indicating the shape differentiation characteristics of the part so as to better reflect the difference between the shape class and the detail of the part. The assembly information code segment for indicating the assembly modes of the parts can be designed to comprise one or more assembly mode indication code bits, and each assembly mode indication code bit is used for indicating one assembly mode of the parts, so that all the assembly modes of the parts are embodied by the assembly information code segment, and the number of the code bits of the assembly information code segment is variable. The specification information code section for indicating the shape and specification of the part comprises specification and model code bits for indicating the shape and specification model of the part and is used for reflecting the difference of the shape and specification types of the part; the part of each shape specification model can be designed to correspond to different size parameters, the size parameters of the part of each shape specification model comprise size data information of each size dimension contained in the corresponding shape specification model, on the design concept, a size information code segment used for indicating the size parameters of the part can be designed and contained in the classification coding number of the part, the size information code segment comprises one or more size data code bits, the number of the size data code bits contained in the size information code segment in the classification coding number of the part is the same as the number of the size dimensions contained in the shape specification model of the corresponding part, and each size data code bit is used for recording the size data information of one size dimension contained in the shape specification model of the corresponding part so as to reflect the size data difference of the part on different size dimensions. Of course, other information code segments can be designed in the classification code number of the part to contain other different code bit information.

Based on the above design concept, in the classification code number of the programmed part, six code segments should be designed altogether, each code segment includes one or more code bits, and the number of basic data bits of each code bit is 2 bits. The first code segment is an agricultural machinery type code segment used for indicating the type of an agricultural machinery product, and only one code bit can be designed for indicating different types of agricultural machinery product types, such as a mini-tiller represented by 01 and a harvester represented by 02. The second code segment is a function information code segment used for indicating the function type of the part to which the part belongs, and only one code bit can be designed for indicating different function types, such as 01 for a power module, 02 for a transmission module and the like. The third code segment is a shape information code segment for indicating the shape characteristics of the part, wherein shape category information code bits for indicating the shape categories of the part are designed, for example, 01 represents a pipe, 02 represents a ring, etc., and shape characteristic information code bits for indicating the shape differentiated characteristics of the part are also designed, and the shape differentiated characteristics corresponding to each shape category are different, for example, the shape characteristic information code bit corresponding to the pipe part (the shape category information code bit is 01) can be designed to represent a hollow special-shaped pipe, 02 represents a hollow straight pipe, 03 represents a hollow bent pipe, 04 represents a solid special-shaped pipe, 05 represents a solid straight pipe, 06 represents a solid bent pipe, 07 represents a flexible pipe, and for example, the shape characteristic information code bit corresponding to the pipe part (the shape category information code bit is 02) can be designed to represent a circular ring, 02 represents a semicircular ring, 03 represents a hoop, etc, 04 for a sleeve, 05 for a washer, 06 for a full core sleeve, 07 for a half full core sleeve, 08 for a profile sleeve, etc. The fourth code segment is an assembly information code segment for indicating an assembly mode of a part, the assembly information code segment can be designed to comprise one or more assembly mode indication code bits, and each assembly mode indication code bit is used for indicating one assembly mode of the part, such as 01 for welding, 02 for bolt connection, 03 for screw connection, 04 for thread connection, 05 for pin connection, 06 for card slot connection and the like; in the design of the classified coded signal of this embodiment, it is desirable to embody all the assembly manners of the component by the assembly information code segments, so that the number of the assembly manner indication code bits included in the assembly information code segments of different components is different, which also causes the number of the code bits of the assembly information code segments in the classified coded signal to be variable. The fifth code segment is a specification information code segment for indicating the shape specification of the part, and only one code bit can be designed to reflect the difference in the shape specification types of the part, for example, 01 represents a cubic specification, 02 represents a cylindrical specification, 03 represents a spherical specification, 04 represents a bent pipe specification, 05 represents a bent sheet specification, 06 represents a regular polygon specification, and the like; meanwhile, the part of each shape specification model can be designed to correspond to different size parameters, the size parameter of the part of each shape specification model comprises size data information of each size dimension contained in the corresponding shape specification model, therefore, the sixth code segment for indicating the size parameter of the part can be designed to comprise one or more size data code bits, the number of the size data code bits specifically contained is the same as the number of the size dimensions contained in the shape specification model of the corresponding part, each size data code bit is used for recording the size data information of one size dimension contained in the shape specification model of the corresponding part, for example, the size information code segment corresponding to the cubic specification part (specification information code segment is 01) can be designed to comprise three size data code bits of length dimension, width dimension and height dimension, and the size information code segment corresponding to the cylindrical specification part (specification information code segment is 02) can be designed to comprise a diameter dimension, Size data code bits of two dimension dimensions of height dimension, size data code bits of only one dimension of diameter dimension can be designed in the size information code segment corresponding to the spherical specification part (the specification information code segment is 03), size data code bits of two dimension dimensions of diameter dimension and length dimension can be designed in the size information code segment corresponding to the elbow specification part (the specification information code segment is 04), and length dimension can be designed in the size information code segment corresponding to the elbow specification part (the specification information code segment is 05), size data code bits of three size dimensions of width dimension and thickness dimension, and size data code bits of n +1 size dimensions including height dimension and n side length dimensions can be designed in a size information code segment corresponding to the specification of the regular polygon (the specification information code segment is 06), wherein n represents the number of multi-deformation edges of the cross section of the regular polygon. In the present embodiment, since the size data code bits in the size information code segment are code bits for recording as data, the number of data bits of the size data code bits is not limited to the 2-bit number, and can be recorded in a default data unit (for example, mm) in accordance with the number of bits of an actual data value.

Thus, in the present embodiment, the table of the sorted part classification code numbers for agricultural products is shown in table 1, and the table of the part classification code numbers for agricultural products is shown in fig. 2, for example.

TABLE 1

Fig. 2 shows a code of a series of mini-tiller handrail frame decoration covers, the code is '01040302030303030603320604', the part is a part of a mini-tiller control module, the part belongs to a cover part in a box cover box, 4 screw assembling modes and a clamping groove assembling mode exist between the part and other parts, the part is of a 01 cube specification, and the length, the width and the height of the part are 32mm, 6mm and 4mm respectively.

By the aid of the coding mode, each part can have an independent classification code number, and similarity comparison judgment of parts is facilitated through the classification code numbers of the parts.

In the corresponding process of the topological relation, the common connection parts of the two parts to be evaluated, that is, parts with more connection relations with other parts in the parts to be evaluated, are determined first; the determination of the common connection parts is helpful for finding the position connection corresponding relation of the rest parts better, so that the topology related part pairs with the same position connection relation in the part connection topology relation graphs of the two parts to be evaluated are determined.

For example, in the part connection topological relation diagram of two components shown in fig. 3, the gray circles in the components represent that the two components can find parts with topological relations corresponding to each other, and the parts with the topological relations corresponding to each other are numbered identically. The parts 1 are public connecting pieces in the parts, the parts with the numbers of 2-10 are common connecting pieces, and the parts with the numbers of 11, 12 and 13 are parts which cannot find the topological relations and correspond to each other.

d1) recording the two parts to be evaluated as a part A and a part B respectively, and counting the number N of parts contained in the two parts to be evaluated respectively_AAnd N_BAnd the number N of topologically related part pairs contained in the two parts to be evaluated₁And further determining the number N of parts which cannot be found in the same position connection relationship in the part A and the part B₂＝N_A-N₁And the number N of parts in the part B which cannot be found in the part A with the same positional connection relation₃＝N_B-N₁。

Based on the classification code numbers of the parts determined in step a) of this embodiment, the processing procedure for comparing the similarity between the classification code numbers of two parts in the pair of topology-related parts in this step specifically includes: calculating the shape similarity TS of the two parts according to the shape information code segments in the classification code numbers of the two parts_i(ii) a Calculating the assembly similarity AS of the two parts according to the assembly information code segments in the classification code numbers of the two parts_i(ii) a Determining the size similarity SS of the two parts according to the specification information code segment, the assembly information code segment and the size information code segment in the classification code numbers of the two parts_i。

In the embodiment, as the agricultural machine part is based on a universal product platform, different productsThe components of the family of agricultural machines can be universal and thus have a shape similarity TS_iThe similarity between the agricultural machinery category code segment and the functional information code segment does not need to be calculated in the calculation, and the similarity of the codes of the part shape information code segments is mainly compared, namely the third code segment. For parts with the same shape class and shape-differentiated features, there is a set relationship as shown in fig. 4 that their shape class information code bits are necessarily the same (i.e., the same shape class) when they are contained and contained, i.e., the same shape feature information code bits (i.e., the same shape-differentiated features), and their shape feature information code bits are not necessarily the same (i.e., the same shape-differentiated features) for parts with the same shape class information code bits (i.e., the same shape class). Therefore, in this embodiment, the shape similarity TS of the two parts is calculated according to the shape information code segments in the classification code numbers of the two parts in the topology related part pair_iThe specific determination method is as follows: if the shape type information code bit and the shape characteristic information code bit in the shape information code segment of the two parts are the same, the shape similarity TS of the two parts is judged_i1 is ═ 1; if the shape type information code bits in the shape information code segments of the two parts are the same, but the shape characteristic information code bits are different, the shape similarity TS of the two parts is judged_i0.5; if the shape type information code bit and the shape characteristic information code bit in the shape information code segment of the two parts are different, the shape similarity TS of the two parts is judged_i0. I.e. as shown in table 2.

TABLE 2

Because there may be one or more assembly methods between parts of an agricultural machine, different assembly methods often result in differences in the similarity of two components. After parts corresponding to each other in topological relation are determined, it is necessary to determine which respective assembly modes exist in the corresponding parts, and corresponding assembly mode indication code bits of corresponding numbers in the assembly information code segments to the assembly modes, where each assembly mode indication code bit is used for indicating one assembly mode possessed by the part. Assembling phaseSimilarity AS_iThe calculation of (3) is to count the number of the same assembly modes, and finally, the ratio of the number of the same assembly modes to the number of all the assembly modes contained in the two parts is calculated to obtain the size of the assembly similarity. Therefore, in this embodiment, the assembly similarity AS of the two parts is calculated according to the assembly information code segments in the classification code numbers of the two parts in the topology-related part pair_iThe specific calculation form is as follows:

For mechanical parts, there are cases of different external dimensions, appearances, even assembly modes, etc., and thus, the similarity determination of the parts is influenced to a certain extent, and the shape similarity determination is also required. According to the definition of size, shape and assembly mode, the parts with unique assembly mode have different external dimensions and appearance, and the parts with different appearances have different sizes.

In this embodiment, the criterion of linear distribution that scores the size of the shape similarity is used, and therefore the size similarity SS of the two parts is determined according to the specification information code segment, the assembly information code segment, and the size information code segment in the classification code numbers of the two parts in the pair of topologically-related parts_iThe specific calculation form is as follows:

if the specification information code segments of the two are the same, the assembly information code segments of the two are also completely the same, which indicates that the assembly modes are the sameAnd if the size data information of the corresponding size dimension in the size information codes of the two parts is the same, judging the size similarity SS of the two parts_i＝1；

If the specification information code segments of the two parts are the same, the assembly information code segments of the two parts are also completely the same, the assembly mode is the same, but the size data information of the corresponding size dimensions in the size information codes of the two parts is not completely the same or different, and the difference of the different size data values of the size dimensions is less than or equal to 10%, the size similarity SS of the two parts is judged_i＝0.8；

If the specification information code segments of the two parts are the same, the assembly information code segments of the two parts are also completely the same, the assembly mode is the same, but the size data information of the corresponding size dimensions in the size information codes of the two parts is not completely the same or different, the different size data value difference of at least one size dimension is more than 10%, but the different size data value difference of each size dimension is less than or equal to 20%, then the size similarity SS of the two parts is judged_i＝0.7；

If the specification information code segments of the two parts are the same, but in the assembly information code segments of the two parts, all the assembly information code segments of one part are the same as part of the assembly information code segments of the other part, which indicates that one part has a unique assembly mode, the size data information of corresponding size dimensions in the size information codes of the two parts are not completely same or different, and the difference of different size data values of the size dimensions is less than or equal to 10%, the size similarity SS of the two parts is judged_i＝0.6；

If the specification information code segments of the two are the same, but the assembly information code segments of the two are the same, wherein all the assembly information code segments of one part are the same as part of the assembly information code segments of the other part, which indicates that one part has a unique assembly mode, the size data information of corresponding size dimensions in the size information codes of the two are not completely the same or different, the difference of different size data values of at least one size dimension is more than 10%, but the difference of different size data values of each size dimension is less than or equal to 20%, then the two parts are judged to be identicalDimensional similarity SS of parts_i＝0.5；

If the specification information code segments of the two parts are the same, but the assembly information code segments of the two parts are different from each other, the two parts are both provided with unique assembly modes, the size data information of corresponding size dimensions in the size information codes of the two parts is also different from each other or different from each other, and the difference of different size data values of the size dimensions is smaller than or equal to 10%, the size similarity SS of the two parts is judged_i＝0.3；

If the specification information code segments of the two parts are the same, but the assembly information code segments of the two parts are different from each other, the two parts are both provided with unique assembly modes, the size data information of corresponding size dimensions in the size information codes of the two parts is also different from each other or different from each other, the different size data value difference of at least one size dimension is more than 10%, but the different size data value difference of each size dimension is less than or equal to 20%, the size similarity SS of the two parts is judged_i＝0.2；

If the specification information code segments of the two parts are the same, but the assembly information code segments of the two parts are completely different, the two parts are shown to have no similarity completely, or the different size data values of at least one size dimension in the size information codes of the two parts have a difference of more than 20 percent, the two parts have a larger size difference, and the size similarity SS of the two parts is judged_i＝0.1；

If the specification information code segments of the two parts are different, the specification of the two parts is completely different, and the size similarity SS of the two parts is judged_i＝0。

Size similarity SS_iThe value relationship of (A) is shown in Table 3.

TABLE 3

Shape similarity TS through product real object comparison parts_iAssembly similarity AS_iAnd the size similarity SS_iOf the parts of higher similarity, the assembly connection contained between the partsThe more similar the relationship, and thus the assembly similarity AS_iThe method is particularly important for calculating the similarity of parts; size similarity SS_iAlso in a sense that the determination of (2) also includes the determination of the part type, and thus the size similarity SS_iIs determined as the ratio of similarity of shape TS_iThe decision of (a) is important. For this purpose, the part similarity PS of the two parts is determined_iGiving the shape similarity TS of the parts_iAssembly similarity AS_iAnd the size similarity SS_iRespectively given a weight of 0.2, 0.5 and 0.3, thus determining the shape similarity TS of the two parts in the pair of topologically related parts_iAssembly similarity AS_iAnd the size similarity SS_iThen, the part similarity PS of the two parts is calculated according to the following formula_i：

PS_i＝0.2TS_i+0.5AS_i+0.3SS_i。

the greater the value of the resulting similarity value US, the greater the similarity of the two parts to be evaluated. For example, a similarity evaluation index of two parts to be evaluated may be formulated in the manner of table 4.

TABLE 4

When the similarity of the two parts to be evaluated is less than 0.6, the similarity is not high, and the two parts to be evaluated are reserved to provide a choice for the configuration of the whole machine without considering the mutual universality; when the similarity of two parts to be evaluated is 0.6-0.8, the parts to be evaluated have certain similarity, but the universality is not strong enough, and whether one redundant part is reserved or eliminated needs to be considered; when the similarity of the two parts to be evaluated is 0.8-0.9, the similarity of the parts is high, the universality is strong, the part which is relatively not suitable for practical application can be eliminated, and the reuse degree of the part is improved; when the similarity of two parts to be evaluated is 0.9-1, the similarity of the two parts is extremely high, and the parts should be generalized to leave the better part.

Calculation example:

based on the embodiment, the reasonability of the method is verified by utilizing a model calculation example according to the agricultural machinery component similarity evaluation method based on the system coding provided by the invention. This calculation example lists 3 comparative typical and representative component similarity calculation examples.

The agricultural machinery is divided into a plurality of product families, such as mini-tillers, harvesters, conveyers and the like, each family is subdivided into a plurality of series, different series have differences in structural composition and design concept, and the agricultural machinery of the same series can have different styles, so that the agricultural machinery of the same series have more or less differences in appearance, local design and the like.

Fig. 5 and 6 are a three-dimensional simulation diagram and an explosion diagram of a handrail frame mechanism of a micro-cultivator respectively, and the parts are composed of 22 parts in total. In order to more clearly embody the calculation flow, the calculation results and the evaluation, the series of handrail mechanisms shown in fig. 5 and 6 are taken as reference, and the similarity calculation is respectively carried out on the series of handrail mechanisms and the mini-tiller handrail mechanisms which are the same in series but different in part number, the same in series and the same in part number and different in series.

In the design of product parts in the same series, structural improvement is often encountered to form parts of different models, resulting in different part numbers of products.

Fig. 7 and 8 are a three-dimensional simulation diagram and an explosion diagram of a series of mini-tiller handrail frame mechanisms respectively, and the mini-tiller handrail frame mechanisms are composed of 23 non-standard parts in total, and compared with the mini-tiller handrail frame mechanisms in fig. 5 and 6, the mini-tiller handrail frame mechanisms are respectively different in the aspects of appearance size, assembly mode and the like of partial parts.

Taking the armrest frame decorative cover with the part number of 10 in fig. 6 and 8 as an example, the 10 th topological-related part pair of the two parts is recorded as belonging to the two parts, and the part similarity calculation of the two parts is performed.

The armrest frame decorative cover belongs to a cover part in a box cover and box part in a coding table by observation and table lookup, the shape information code segments are all 0302, and the shape similarity TS of the two parts at the moment₁₀Is 1.

For the assembly similarity of the two parts, the handrail frame decorative cover of fig. 8 is connected with the handrail support arm (number 20) through 3 screws, connected with the pull rod fixing seat (number 9) through 1 screw, and connected with the handrail support arm through a clamping groove, so that the handrail frame decorative cover of fig. 8 is arranged from small to large according to the assembly mode codes, and the assembly information code segment of the handrail frame decorative cover of fig. 8 is '0303030306'; the armrest cover decorative frame of fig. 6 has 1 screw connection with the armrest support arm (number 20), 1 screw connection with the pull rod fixing base (number 9), and a card slot connection with the armrest support arm, and is arranged from small to large according to the assembly mode code, and the assembly information code segment of the armrest cover decorative frame of fig. 6 is obtained as '030306'. According to the method for calculating the assembling similarity of parts, the assembling mode indicating code bits of the same assembling mode of the two handrail frame decorative covers are 3 and are 03, 03 and 06 respectively, the handrail frame decorative cover of figure 8 also has 2 assembling mode indicating code bits, namely 03 and 03, which can not find the corresponding group in figure 6, and the handrail frame decorative cover code group of figure 6 corresponds to the group of the handrail frame decorative cover of figure 8, so the assembling similarity AS is large₁₀Comprises the following steps:

AS₁₀＝3/(3+2+0)＝0.6；

for the shape similarity judgment, the specification information code segments of the two handrail decoration covers are the same, but the handrail frame decoration cover in figure 8 has 2 more assembly modes compared with the handrail frame decoration cover in figure 6, and the assembly information code segments of the two handrail decoration covers are different from each other, and the size data information of corresponding size dimensions in the size information codes of the two handrail decoration covers are also different from each other, but the different size data values of the size dimensions are different from each otherAre all less than 10 percent, and the size similarity SS of the two handrail decorative cover parts is determined according to the part size similarity determination standard determined in the previous embodiment₁₀The size is 0.3.

Thus, the part similarity PS of the two armrest frame decorative covers of the fig. 6 and the fig. 8 is obtained₁₀Comprises the following steps:

PS₁₀＝0.2×1+0.5×0.6+0.3×0.3＝0.59；

according to the calculation method of the part similarity, the part similarity calculation of the flow shown above is carried out on all corresponding parts of the two components, at this time, the topological relations of 22 parts are corresponding, the part numbers and the part similarity conditions in the topological related part pairs with the part similarity different from 1 are listed in the table 5, the part similarity of two parts of the topological related part pairs which are not listed is 1, and the part similarity of the parts which are not found out of the corresponding relations does not naturally exist or is not listed.

TABLE 5

In fig. 6 all parts find corresponding parts in fig. 8, while the part with number 23 in fig. 8 does not find parts corresponding to the topological relationship in fig. 6. According to the calculation method of the similarity of the components, the sum of the similarity of 22 parts corresponding to the topological relation is performed, and then the sum of the number of the parts corresponding to the topological relation and the number of the parts not corresponding to the topological relation is divided to obtain the similarity value US of the components shown in fig. 5 and 6 and the components shown in fig. 7 and 8, namely:

US＝(19×1+0.59+0.83+0.73)/(22+0+1)＝0.919；

from the similarity calculation result, it is known that the similarity between these two components is extremely high, and the two components should be merged into one component so as to leave the component which is more reasonable.

In the design of the same series of product components, optimization of the size may be encountered, which results in different external dimensions of the product, but the total number of parts is still the same.

The three-dimensional simulation drawing and the explosion drawing of the mini-tiller handrail frame mechanism of a certain enterprise model with the same number of parts are shown in fig. 9 and 10, the number of the parts is 22, but the three-dimensional simulation drawing and the explosion drawing have individual differences from the three-dimensional simulation drawing and the explosion drawing of the mini-tiller handrail frame mechanism of fig. 5 and 6 in appearance and size, namely, the parts numbered as 1, 2, 3, 16, 20, 21 and 22 in the drawing.

And calculating the similarity of the parts corresponding to all the topological relations according to a similarity calculation method, wherein the parts corresponding to the topological relations and having the similarity different from 1 are listed in a table 6.

TABLE 6

Therefore, after calculating the part similarity corresponding to all 22 topological relations of the two components, the similarity values US between the components shown in fig. 5 and 6 and the components shown in fig. 9 and 10 can be calculated, namely:

US＝(15×1+6×0.88+0.82)/22＝0.959；

according to the similarity calculation result, the similarity of the two components is extremely high, the two components have strong universality, and the two components should be combined into one component or only the more reasonable component is left.

It is possible that different series of parts of the agricultural machine have a certain similar function, but they differ greatly in terms of appearance, assembly, etc. The mini-tiller handrail frame mechanism shown in fig. 11 and 12 is composed of 19 non-standard parts, and the mini-tiller handrail frame mechanism shown in fig. 5 and 6 belongs to the same mini-tiller handrail frame mechanism, but the mini-tiller handrail frame mechanism and the mini-tiller handrail frame mechanism belong to different series, so that the mini-tiller handrail frame mechanism has great difference in appearance. After the corresponding topological relations are found, the topological relations of the handrail rubber sleeves numbered 2 and 3 are corresponding, and the topological relations of other parts cannot be corresponding. The results are listed in table 7 for parts in which the topological relationships correspond but the part similarity is not 1.

TABLE 7

According to the similarity calculation method of the components, the similarity values US of the components shown in FIGS. 5 and 6 and the components shown in FIGS. 11 and 12 are obtained as follows:

US＝2×0.88/(2+20+17)＝0.045；

because the two parts have too large difference in the topological relation of the parts, the difference of appearance and structure is caused, and finally, the difference and the similarity of the parts are large. Therefore, the two parts can be judged to be stored, and more configuration options can be provided for the subsequent whole machine design of the mini-tiller.

In summary, the invention provides an agricultural machine component similarity evaluation method based on system coding, which performs component similarity calculation on the shape similarity, the part assembly similarity and the part size similarity of a part according to a part coding mode aiming at the characteristics of an agricultural machine product and the proposed topological relation of corresponding components, thereby realizing the similarity calculation of the component and setting a threshold value to perform similarity evaluation. The effectiveness and the reliability of the agricultural machinery component similarity evaluation method based on the system coding are verified through a plurality of model calculations in the calculation example. By evaluating the similarity of the components, the components of the module library can be integrated, so that the components with more reasonable design and higher reuse degree are left, redundancy or the components with unreasonable relative design are eliminated, and the management of the components in a product platform is facilitated; more and more optimal alternatives can be provided for the configuration of the product, and the innovative design of the product is enhanced.

Finally, the above embodiments are only for illustrating the technical solutions of the present invention and not for limiting, although the present invention has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that modifications or equivalent substitutions may be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all of them should be covered in the claims of the present invention.

Claims

1. A method for evaluating similarity of agricultural machinery components based on system coding is characterized by comprising the following steps:

D) evaluating the similarity of the two parts to be evaluated by respectively comparing the number of parts respectively contained in the two parts to be evaluated, the number of topological associated part pairs contained in the two parts to be evaluated, and the similarity of the classification code numbers of the two parts in each topological associated part pair; the method comprises the following steps:

d1) recording the two parts to be evaluated as a part A and a part B respectively, and counting the number N of parts contained in the two parts to be evaluated respectively_AAnd N_BAnd the number N of topologically related part pairs contained in the two parts to be evaluated₁And further determining the number N of parts which cannot be found in the same position connection relationship in the part A and the part B₂＝N_A-N₁And in component B cannotFinding the number N of parts with the same position connection relation in the component A₃＝N_B-N₁；

d2) Aiming at two parts in any ith topological correlation part pair contained in the part A and the part B, comparing the similarity of the classification code numbers of the two parts, and determining the part similarity PS of the two parts_i(ii) a Wherein, the similarity of the classification code numbers of the two parts in the topological correlation part pair is compared, and the part similarity PS of the two parts is determined_iThe specific mode is as follows: according to the classification code numbers of the two parts, the shape similarity TS of the two parts is respectively determined_iAssembly similarity AS_iAnd the size similarity SS_i(ii) a Then, the part similarity PS of the two parts is calculated_i：

PS_i＝0.2TS_i+0.5AS_i+0.3SS_i；

2. The agricultural machinery component similarity assessment method based on system coding according to claim 1, wherein in the classification coding number of the part, the shape information code segment for indicating the shape feature of the part comprises shape class information code bits for indicating the shape class of the part and shape feature information code bits for indicating the shape differentiated feature of the part.

3. The method for assessing the similarity of agricultural machinery components based on system codes according to claim 2, wherein the step d2) of comparing the similarity of the classification code numbers of the two parts in the topology-related part pair comprises:

4. The agricultural machinery component similarity assessment method based on system coding according to claim 1, wherein in the classification coding number of the part, the assembly information code segment for indicating the assembly mode of the part comprises one or more assembly mode indication code bits, and each assembly mode indication code bit is used for indicating one assembly mode of the part.

5. The method for assessing the similarity of agricultural machinery components based on system codes according to claim 4, wherein the step d2) of comparing the similarity of the classification code numbers of the two parts in the topology-related part pair comprises:

Wherein n is₁Indicating the number of the indication code bits with the same assembly mode in the assembly information code segments of the two parts in the topology associated part pair; n is₂Of two parts representing the topologically-related part pairThe number of the indication code bits of different assembly modes exists in the assembly information code segment of the first part relative to the assembly information code segment of the second part; n is₃And indicating the number of indication code bits of different assembly modes in the assembly information code segment of the second part relative to the assembly information code segment of the first part in two parts representing the topology associated part pair.

6. The agricultural machinery component similarity evaluation method based on the system code according to claim 1, wherein in the classification code number of the part, a specification information code segment for indicating the shape specification of the part comprises specification model code bits for indicating the shape specification model of the part; the parts of each shape specification model are corresponding to different size parameters, and the size parameters of the parts of each shape specification model comprise size data information of each size dimension contained in the corresponding shape specification model;

7. The method for assessing the similarity of agricultural machinery components based on system codes according to claim 6, wherein the step d2) of comparing the similarity of the classification code numbers of the two parts in the topology-related part pair comprises:

If the specification information code segments of the two are the same, the assembly information code segments of the two are also completely the same, and the size data information of each corresponding size dimension in the size information codes of the two are also the sameAnd judging the size similarity SS of the two parts_i＝1；

If the specification information code segments of the two parts are the same, but in the assembly information code segments of the two parts, all the assembly information code segments of one part are the same as part of the assembly information code segments of the other part, the size data information of corresponding size dimensions in the size information codes of the two parts are not completely the same or different, and the difference of different size data values of the size dimensions is less than or equal to 10%, the size similarity SS of the two parts is judged_i＝0.6；

If the specification information code segments of the two are the same, but the assembly information code segments of the two are different from each other, the size data information of each corresponding size dimension in the size information codes of the twoAre not completely or differently different, and the difference of the different size data values of all the size dimensions is less than or equal to 10%, then the size similarity SS of the two parts is judged_i＝0.3；