Research On CAD/CAM Integrated System Of Reticulated Structures

Reticulated structures are widely used all over the world. Theory study, which benefit from the success of engineering construction, has developed rapidly. By now, reticulated structures already have a perfect theoretical basis and practical experience. The domestic reticulated structure industry still pursues an extensive production that has resulted in a low level of mechanization and processing errors, which are unable to meet the standard's requirements. The quality of projects cannot be well guaranteed. In addition, Bolt-ball Joints is a typical semi-rigid joint and has capacity of bearing partial bending moments. Its structure calculation model is a member system with semi-rigid connections. To a certain extent, an imperfect structure calculation model will affect the correctness of the internal force analysis of structure. Therefore, researching on the bending stiffness of bolt-ball joint is very important for the design of reticulated structures. And it is particularly important for the study of the influence of processing errors in the internal force analysis.The reticulated structure shows a new trend. It's not only requires a high demand of manufacturing precision but also improving the non-standard production capacity is rather important. It is reasonable to say that the traditional manufacturing process has hindered the rapid development and applications of reticulated structures. Besides, the contradiction between the collaboration requirement of the modern design process and the traditional operation model has become increasingly prominent. The traditional design and production of reticulated structures are usually carried out separately, which will be very difficult for information transmission, causing misunderstanding. However, a highly integrated platform for engineering design and automatic machining will effectively ease the contradiction.At present, CAD / CAM technology has made considerable progress in the manufacturing and CNC machine tools have been widely used. Promoting its application in the reticulated structures manufacturing industry will be able to completely reform and upgrade traditional industry. A reticulated structure CAD/CAM system for CNC machining can provide a highly integrated platform for engineering design and automatic machining. CAD / CAM technology and other advanced manufacturing technologies can be used to improve the accuracy and non-standard production capacity. Not only will it save a lot of time but it will also increase the considerable economic benefits.Based on the development status of the reticulated structures manufacturing industry at home and abroad and the successful application experience of advanced manufacturing technology in other industries, a bolt-ball joints CAD/CAM system for CNC machining is proposed in reticulated structures design softwares. It aims to build an integrated platform for engineering design and automatic machining. This paper is based on effects on behavior of reticulated structures from processing errors and the integration solution of CAD/CAM system as research objects. Main contents of this thesis are provided below:(1)This study launches investigations of real domestic manufacturing of bolt-ball frame to make a preliminary research on processing technology and manufacturing deviation of bolt-ball frame after investigating processing equipment, work processes and management. In addition, relevant error dates are collected and analyzed.(2)The bolt-ball joint is a typical semi-rigid joint. According to its geometric construction features, simplified calculating formula for bending stiffness of bolt-ball joints is obtained, which based on the assumption of plane section and under pure bending condition. It aims to build a perfect structure theoretical analysis model, which laid the theoretical foundation for the research of effects on behavior of reticulated structures from processing errors.(3)Combined the perfect structure theoretical analysis model and the actual distribution law of processing errors, the main structure which adopts bolt-ball joints is analyzed by STCAD software in the conditions of different processing errors. In this way,the law of the influence on different forces in reticulated structures due to processing errors is obtained.(4)Combined with characteristics of reticulated structures and parametric design principles, this article carried out a detailed analysis on the overall design scheme of parameterized systems. However, this paper gives a comprehensive study on the problems of parameterized systems combined with based-constraint parametric design, and also discusses the parameter model and parameter-driven mechanism in detail,laying foundation for the System Development.(5)A reticulated structure CAD/CAM system for CNC machining is proposed in reticulated structures design softwares.This paper gives a comprehensive study on the design principles and methods of integrated system. In addition, a full data-related engineering information management system is established by access software. Finally, an integration solution of the reticulated structure CAD/CAM system has been realized on SolidWorks platform.