VIRTUAL PARAMETRIC MECHANICAL DESIGN ASSOCIATED WITH CAD ENVIRONMENT AND DATABASE

Abstract

The paper aims to approach a methodology of virtual parametric design in the mechanical field. The method proposes the transition from the manual calculation of the design stages, usually indicated by the design guides, followed by a CAD representation, to a new method that involves parametric virtual modeling in a CAD environment and the correlation of the CAD model with an external database. All design parameters and calculation steps are integrated into an Excel file. In the list of the parameters of the general CAD model, besides the parameters of the model, user parameters that can be found in all the design stages (initial or calculated variables) are entered. The spreadsheet also contains lists with different values of catalog quantities (dimensional or technological). The user selects in the spreadsheet different values of the user parameters that lead through the calculated fields to some geometrical named parameters of the model. In the list of parameters of the CAD model it is made the connection with the spreadsheet whose parameters are attached. The user assigns to each parameter of the CAD model the corresponding parameter named and calculated from the Excel database. One can choose to automatically update the CAD model in relation to the values associated with the parameters. The update leads to a CAD representation consistent with the user-selected initial design data of database. The work demonstrates the concept by applying it to the design of a cutting tools for processing the teeth of spur and helical gears. Students can witness by means of an applied virtual concept short-term results associated with several project versions and can quickly understand the influence of different design parameters on the CAD model making comparisons or different analyses. Thus, the virtual project eliminates the high realization time and the computational effort in the classical method, as well as the physical models in the laboratory for demonstrating the different technical aspects.