Implementation of VDI Guidelines in Parametric 3D CAD Systems and Their Functional Extension to Dynamically Associative Optimization Tools

Design guidelines, such as the VDI guidelines, help the designer in the synthesis of gears and mechanisms for standard recurring tasks. The guidelines provide graphical and computational methods, leading the designer systematically to solve the task. In addition to the actual synthesis process, they often contain diagrams and formulas to support identification of a “good” mechanism. This paper shows how the synthesis method derived from such guidelines can be integrated into modern 3D parametric CAD systems. In addition, design criteria can be used in the search for “good” mechanisms which are specifically tailored to the particular application and thus cannot be covered in general guidelines. In order to take into account such criteria in the individual optimization, the editor should work dynamically, interactively and associatively. Simultaneously with the modification of the mechanism via the graphical input device of his of her CAD system, the editor has to identify and manage the new mechanism dimensions, space requirement and the quality of its criteria. The paper clearly shows also that by using design guidelines in conjunction with parametric CAD systems, synergies are realized. The design engineer is offered a good guide to the solution of the task in his or her usual working environment. The use of features and parameters in CAD systems is explained and solutions are shown to design the mechanism according to requirements. Typical applications are shown using the 3D CAD systems CATIA V5 and Pro/Engineer Wildfire 5.0.