Research And Development Of Semi-trailer Rapid Design System

Semi-trailer, the important part of truck especially heavy vehicles, is a kind of broad-spectrum special vehicle. Because of its quick, motor, flexible, and secure advantage which other modes of transportation cannot replace, semi-trailer has gradually become the main way of road transportation in China. In order to save energy, reduce the transportation cost and improve logistics efficiency, The Ministry of Transport and the National Development and Reform Commission has vigorously promoted the standard-setting and pilot work of the semi-trailer meeting the demand of drop and pull transport since2009, so the semi-trailer meeting the demand of drop and pull transport has become the focus of the current research. However, the overall design level of semi-trailer in China is not high, the design methods are out of date, and it is difficult to meet the user individualized requirements in different service conditions. As a result, the service life of the semi-trailer in some challenging conditions is not long, while the quality of most semi-trailer in China is bigger than the same products abroad, which lead to low load ratio and big oil consumption. In order to meet the user individual requirements and design a lightweight semi-trailer with high quality and high efficiency, a semi-trailer rapid design software system based on the fusion techniques is built by studying rapid design theories, methods and key technologies suitable for semi-trailer. The establishment of this system makes a great significance for semi-trailer enterprise which can enhance their ability of fast response to market demand and help them dominate an advantageous position in market competition. The main work in this paper is as follows:1)It is shown that majority existing design for semi-trailer is superfluous while local of the design is insufficient by summarizing the research of the numerical analysis of the stiffness and strength, fatigue analysis and experimental results on several categories of semi-trailer frame assembly and suspension assembly. Then the optimization structure of major semi-trailer components in different service condition is concluded in line with the principle of reducing redundancy filling inadequacy. As a result, the rapid design model of lightweight semi-trailer which can meet user personalized requirements is established.2) The selection of rapid design methods which is suitable for semi-trailer is made by doing a systematic study of the rapid design theoried, methods and characteristics of semi-trailer structure. For the concept design, the case-based reasoning fusion with rule-based reasoning technology is used to reason overall design scheme of the semi-trailer; For assembly parts design, modular technology is used to make modular, standard disassemble of semi-trailer, and semi-trailer design is disassembled as many modules such as frame assembly, connection device, suspension assembly, axle assembly and bearing assembly. Then make parametric, variational design for each child module; For detail design, such as weight reducing hole, the frame strengthen board, UG user defined features and reusable libraries methods are used to improve the design efficiency.3) According to the research results, related national standards and manuals, semi-trailer core parameter database, including rule library, expression library, size parameters database and template library, is established to provide data support for semi-trailers rapid design.4) The whole design process and realization method of semi-trailer rapid design system are put forward. Then the development process and key technology of the concept design system, parts rapid design system, reusable libraries and user role management system are done. Finally, it is verified that the system is effective through the design case for a certain type of semi-trailer.