Research And Application Of Parametric Drawing Design Based On Secondary Development Of AutoCAD

With the continuous change of demand,the function of CAD drawing industry is constantly renovated.The goal of enterprise is to speed up and work efficiently and intelligently.The drawing of the diverse drawings attracts more and more people.In order to expand the field of science and technology conform to the function and user needs change,enterprises adopt CAD technology to develop its own productivity is more and more widely,the CAD category of technical requirements also more and more high,the design of the single drawing function more and more people can't meet the demand of two.Research and development trends of AutoCAD development,namely the parametric drawing method is an important development direction of the two research fields.The technical requirements of production industry is sometimes AutoCAD own function to complete a product of the different size of the mass production of the drawing operation,the workload of the drawing for this situation will be very large.Also put forward two development of parameterized application system on the AutoCAD demand.The relationship between the product and the demand is not clear there is still lack of the software:(1)the need to repeat the design drawing parts drawing,artificial workload is huge;(2)human resources demand increase;(3)the software function has high characteristic of error rate;(4)the parametric design system for draw a single device need to repeat the products.According to the above requirements,developed hot-rolled I-beam drawing system--Taking AutoCAD as the development platform,using VBA two development tool,combined with Access database,realized a parametric drawing system based on AutoCAD environment.The development tools of the system through VBA programming using ActiveX Automation technology to implement AutoCAD.Connect the application to control program and external database through ADO(Active Data Objects)data access technology,realize a type parameter details access storage of product data in the database.By adding and modifying data of control functions to achieve data consistency in Access database modifications in the user interface;otherwise,also can change the data in the Access database,which makes the the user interface will modify the data,finally formed in the AutoCAD interactive parametric drawing system of the system.The whole system is divided into three modules: program login module,parameterized drawing module and data management module.In this paper,three examples are given for the application of parametric drawing design system to verify the validity and practicability of the parametric design drawing method.The system program design will shorten the drawing cycle,drawing process complex as simple,reduce human resources investment and improve work efficiency,AutoCAD intelligent drawing graphics.On the basis of automatically drawing two-dimensional graphics,functions can be expanded: creating menu bar,automatic dimensioning,dynamic parameterization and building of three-dimensional model to achieve more intuitive and intelligent effects.The key technology in the development process,such as the secondary development technology of AutoCAD,ActiveX Automation technology,parametric thinking,intelligent interactive interface design and database connection technology,respectively introduced their functions in this system.The system has an open system structure and the function of each module is clear,guarantee system application of system stability.Through drawing parameters,product design parameters required by the user in the input,in accordance with the interface,the system can be drawn according to the demand of product design.On the one hand,greatly improve work efficiency,simplify the design project,improve the degree of automation design and cost saving,which has the characteristics of simple and quick drawing on the other hand.On the other hand,the practical effect of the system is very strong,and the parametric design concept is rapidly promoted,Which laid a solid foundation for the future development of the application of parametric drawing to the development of three-dimensional product library of ancient building components.