Computer engineering

PhD, technical sciences Virchenko G.A.

Gryaznova G.P.

National Technical University of Ukraine «KPI», Ukraine

 

PERSPECTIVES OF USING OF STRUCTURAL PARAMETRICAL METHODOLOGY FOR MODELLING IN MODERN COMPUTER AIDED DESIGN SYSTEMS

 

Nowadays most of the manufactures have a possibility to choose convenient CAD/CAM/CAE (Computer-Aided Design /Computer-Aided Manufacturing /Computer-Aided Engineering)-products [1] from the wide range of domestic and foreign Computer-Aided Design Systems (CADS) depending on posed problem, scale of production output and economic feasibility.

Along with technical parameters and characteristics selection process of certain CADS software package based on many other factors:

-  current company “standards” at the specific industry;

-  computer systems used by key partners;

-  possibility of software supplier to realize of effective support of CADS and its future development;

- and so on.

Large engineering enterprises, for instance, of shipbuilding, aviation and other industries, as a rule, focus on utilization of various (heterogeneous) CADS for design of every separate group of mechanisms, blocks or devices etc.

As high-level software such multimodular software packages as CATIA, CADDS, Pro/ENGINEER and the others are often used for modeling of complicated cabinet surfaces, engineering communications, pipelines and cable systems.

 Separate blocks design could be held by middle and low-level-software such as SolidWorks, Autodesk Inventor, ÊÎÌÏÀÑ, AutoCAD and others. 

Besides 3D-modelling systems like Autodesk Inventor Professional and SolidWorks are used also for comprehensive analyzes of projected constructions. In particular, it refers to consideration of strength, kinematic and dynamic calculations and other aspects.

Support of data exchange format STEP allows combination of objects designed by different CADS software.

 Despite the fact that up to 90% details and spare parts of the new assembly unit could be completed from existing design libraries of standard and unified products, computer-aided design still remains a time-consuming task.

Applying of various CADS could also complicate design process of complex product consisting of blocks of different purpose and topology.

In connection with this the problem of finding of optimal methods of geometrical modelling of products with CAD/CAM/CAE-systems remains an urgent task for the most industries.

Overwhelming number of up-to-date CADS has  an option of parametric representation of a product in design. In particular, the latest version of CATIA offers so called “soft parameterization”. It allows work with “hard” as well as flexible parametric models. SolidWorks, ÊÎÌÏÀÑ-3D and the other packages support the similar options.

Since shape and dimensions of details are linked into the unified system, it is obviously appropriate to use structural parametric geometrical modelling methodology as the one of scientific directions of applied geometry and engineering graphics [2] for the complex optimization of constructions.

Computer geometrical model building means creation of object’s mathematical description for its (object) definition and subsequent modification.

At that every geometrical component is considered as defined ordered set of separate elements. Thus, investigated object could be the potential part of a more complicated system.

The mentioned approach of a structural parametric modelling is applicable to the multivariate hierarchical structure of any difficulty that may include not only combination of objects, but also combination of processes.

 Since design documentation creation always precedes a development of the production cycle for manufacturing an article, the way of creation of optimal model can be extended and supplemented with facts that take into consideration indicators of subsequent technological processing, resolving by that of existing problem of fragmentation of design and technological tasks.

Despite the fact that the complexity of parametric system increases after the entering of new elements, as a result, in accordance with its abilities and goals manufacturer obtains full optimized cycle of unit construction and manufacturing.

Thus, the search and introduction of new methods of geometric modelling in modern computer systems is actual task for improving quality and reducing the cost of production processes on modern enterprises.

 

Literature:

1. Lee, K., 2004, “CAD system foundation (CAD/CAM/CAE)”, S-Pb.: Peter, 560p.

2. Vanin, V. V., Virchenko, G. A., “Definition and main regulations of structural parametrical geometrical modelling”, Geometrical and computer modelling, 2009, Issue 23, Kharkiv: KHDUKHT, pp. 42-48.