Application of Parametric Variant Technology for Semi-trailer Parts

2023-05-09

Semi-trailer parts are the key parts of the vehicle body, which must meet the performance requirements of many aspects and comply with some regulations and recognized standards. In the past, Chinese semi-trailer parts in the domestic aspect, often only pay attention to the product's own geometric shape, dimensional tolerance, lack of product concept, running reality, processing environment, material status and other aspects of integrated consideration, resulting in some mistakes in the process of localization trial production.

Taking axle series products of a semi-trailer parts limited company of an enterprise as an example, at present, in the process of rapid development, the enterprise has many orders in the product market, different users have different demands for products, and various models and specifications, so the product research and development ability can not keep up. In product development, due to the lack of application of advanced technical means, drawing design work is heavy, repetitive labor, long research and development cycle, design mainly relies on the experience of designers, the lack of scientific analysis, calculation and optimization, design errors often lead to the modification of drawings in the manufacturing process, resulting in unnecessary losses such as waste products and rework.

The research and development level in this field compared with the developed countries, need to carry out scientific research and technical development in the design and manufacture of key parts of semi-trailer (such as sleeves, support, suspension, traction seat and traction pin, etc.), improve our technical level in the design and manufacture of semi-trailer parts.

At present, the design method of the axle series of the enterprise still stays on the manual calculation, so the accuracy and efficiency of the design are greatly reduced. Axle design is a highly experiential industry, and the experience and knowledge accumulated by the designers in the long-term work plays a very important role in the process of axle design. Although CAX technology is applied more and more widely, CAX technology is still mostly at the computer-aided level at present, and it is difficult to upgrade CAX technology for product development to the level of intelligent design. This leap can be realized through artificial intelligence and engineering knowledge. Construct automatic design (Knowledge Based Engineering) system to achieve. In this paper, through the development of computer aided axle design software, the parameter variation design technology is integrated into the process of automatic design modeling, and an automatic assembly system framework is established based on the model. Based on the description and analysis of the framework, a prototype system is presented and its implementation process is described.

1. Basic principle of parametric variant design

Variation design is to select similar examples and modify and improve them on the basis of not destroying the basic principles and structural features of the original design. When the variation design is carried out, the user requirements or design tasks are first decomposed to obtain the basic functional principles and basic performance parameters of the product. According to the -definite algorithm, these basic performance parameters are matched with the parameters in the transaction property table, and the most similar instances are searched from the instance library. Extract the similar instance, refer to the result of optimization calculation, and modify the instance according to the requirements of users on this basis.

In the process of modification, it may be a simple part of the size modification, and the structure is exactly the same, which belongs to the change of product specifications, can be realized through the parametric part model may also be the change of product model, at this time the local change of the product structure, at the same time the size may also change, this is to be realized by the stable mutual combination of parts on the real side. When the structural form or geometric size of a part is changed, the whole assembly also changes with the change of parts, because there is not only dimension connection relation between parts, but also hidden assembly constraint relation (including position relation, connection relation, movement relation, etc.), and the assembly model is not destroyed at this time.

In the process of variation, the basic assembly relations and assembly constraints of the assembly model should be taken into account first, and the assembly performance of the modified assembly should be analyzed at the same time. Based on the reminding rules and knowledge, the assembly performance should be judged and decided. Human-machine interaction is carried out when necessary, and the rules and knowledge are constantly improved through the self-learning function of the assembly model, and finally the variant results are obtained. In the process of assembly performance analysis, some new rules and knowledge may be generated, which should be stored in the assembly rule base and knowledge base. Because there may be some New Testament assembly relationship secret assembly constraints in the process of variation, the assembly mold curse will be constantly updated, and the next variation will refer to the new assembly model. The result of the variation should also be entered into the instance library as a new instance character.

Parametric variation design system of semi-trailer parts is a kind of software to realize parametric variation design of assembly drawing specially developed for semi-trailer parts. Software through language programming to establish the assembly constraints between parts of semi-trailer, enterprises only need to input the necessary parameters according to customer needs, can be driven by the software graphics, the final modified assembly drawing output to the CAD interface, through the printing equipment can be out of the engineering drawing to guide the actual work. Of course, before software is developed, it should be cost-effectiveness, market demand, production scale and cost estimates, and feasibility analysis. The whole product model in the process of variation is also a dynamic model.

Semi-trailer parts are the key parts of the vehicle body, which must meet the performance requirements of many aspects and comply with some regulations and recognized standards. In the past, Chinese semi-trailer parts in the domestic aspect, often only pay attention to the product's own geometric shape, dimensional tolerance, lack of product concept, running reality, processing environment, material status and other aspects of integrated consideration, resulting in some mistakes in the process of localization trial production.

Taking axle series products of a semi-trailer parts limited company of an enterprise as an example, at present, in the process of rapid development, the enterprise has many orders in the product market, different users have different demands for products, and various models and specifications, so the product research and development ability can not keep up. In product development, due to the lack of application of advanced technical means, drawing design work is heavy, repetitive labor, long research and development cycle, design mainly relies on the experience of designers, the lack of scientific analysis, calculation and optimization, design errors often lead to the modification of drawings in the manufacturing process, resulting in unnecessary losses such as waste products and rework.

The research and development level in this field compared with the developed countries, need to carry out scientific research and technical development in the design and manufacture of key parts of semi-trailer (such as sleeves, support, suspension, traction seat and traction pin, etc.), improve our technical level in the design and manufacture of semi-trailer parts.

At present, the design method of the axle series of the enterprise still stays on the manual calculation, so the accuracy and efficiency of the design are greatly reduced. Axle design is a highly experiential industry, and the experience and knowledge accumulated by the designers in the long-term work plays a very important role in the process of axle design. Although CAX technology is applied more and more widely, CAX technology is still mostly at the computer-aided level at present, and it is difficult to upgrade CAX technology for product development to the level of intelligent design. This leap can be realized through artificial intelligence and engineering knowledge. Construct automatic design (Knowledge Based Engineering) system to achieve. In this paper, through the development of computer aided axle design software, the parameter variation design technology is integrated into the process of automatic design modeling, and an automatic assembly system framework is established based on the model. Based on the description and analysis of the framework, a prototype system is presented and its implementation process is described.

1. Basic principle of parametric variant design

Variation design is to select similar examples and modify and improve them on the basis of not destroying the basic principles and structural features of the original design. When the variation design is carried out, the user requirements or design tasks are first decomposed to obtain the basic functional principles and basic performance parameters of the product. According to the -definite algorithm, these basic performance parameters are matched with the parameters in the transaction property table, and the most similar instances are searched from the instance library. Extract the similar instance, refer to the result of optimization calculation, and modify the instance according to the requirements of users on this basis.

In the process of modification, it may be a simple part of the size modification, and the structure is exactly the same, which belongs to the change of product specifications, can be realized through the parametric part model may also be the change of product model, at this time the local change of the product structure, at the same time the size may also change, this is to be realized by the stable mutual combination of parts on the real side. When the structural form or geometric size of a part is changed, the whole assembly also changes with the change of parts, because there is not only dimension connection relation between parts, but also hidden assembly constraint relation (including position relation, connection relation, movement relation, etc.), and the assembly model is not destroyed at this time.

In the process of variation, the basic assembly relations and assembly constraints of the assembly model should be taken into account first, and the assembly performance of the modified assembly should be analyzed at the same time. Based on the reminding rules and knowledge, the assembly performance should be judged and decided. Human-machine interaction is carried out when necessary, and the rules and knowledge are constantly improved through the self-learning function of the assembly model, and finally the variant results are obtained. In the process of assembly performance analysis, some new rules and knowledge may be generated, which should be stored in the assembly rule base and knowledge base. Because there may be some New Testament assembly relationship secret assembly constraints in the process of variation, the assembly mold curse will be constantly updated, and the next variation will refer to the new assembly model. The result of the variation should also be entered into the instance library as a new instance character.

Parametric variation design system of semi-trailer parts is a kind of software to realize parametric variation design of assembly drawing specially developed for semi-trailer parts. Software through language programming to establish the assembly constraints between parts of semi-trailer, enterprises only need to input the necessary parameters according to customer needs, can be driven by the software graphics, the final modified assembly drawing output to the CAD interface, through the printing equipment can be out of the engineering drawing to guide the actual work. Of course, before software is developed, it should be cost-effectiveness, market demand, production scale and cost estimates, and feasibility analysis. The whole product model in the process of variation is also a dynamic model