Application of Heuristic Modeling in the Development of an Algorithm for Generating a Binary Tree of an Object According to a Technical Drawing

This article presents the problem of developing an algorithm for automated reading of a drawing of an object, consisting of three types with the necessary cuts. According to the drawing, a partition of the object into nonderivative figures should be obtained and boolean operations should be identified, with the help of which the final composite figure will be constructed from non-derivative figures. Thus, in the process of solving this problem, a socalled binary tree of the modeled composite figure will be generated. Moreover, it is necessary to take into account the multiplicativity of the solution to this problem and the possibility of choosing optimal solutions. This paper poses a specific problem, in which non-derivative figures can be got using four formbuilding operations available in the arsenal of tools for getting three-dimensional elements in the Compass 3D geometric modeling system, namely, such operations as "extrusion", "rotation", "along the trajectory" and "cross-sections".

Hardware and Software Implementation of Constructive Geometric Models

The article is devoted to the consideration of a number of issues of hardware and software implementation of constructive geometric models. A rich arsenal of theoretical research in the field of constructive geometry has not been properly used for a long time due to the lack of tools for translating such models using computer technology. The development and improvement of the Simplex geometric modeling system, in which any geometric design is considered as a converter of information represented by signals of a geometric nature, has opened the possibility of applying the achievements of geometric science in computing applications, as well as the development of hardware that implements geometric calculation methods and provides a new graphical interface. The concept developed by the authors is aimed at creating specialized accelerators of geometric transformations.

Towards Dynamic Tolerance Analysis Using Bond Graphs

A generic method is proposed by which the effect of tolerances in combination with physical effects such as wear can be analysed on the dynamic behavior of mechanisms. The method uses bond graphs in order to simulate the dynamic behavior under the influence of tolerances and other physical effects. The method has the potential to offer enhanced computer support in tolerance value specification as well as in robust design and model based maintenance. The method has partly been implemented using a combination of a geometric modeling system (FROOM) and a bond graph based physical modeling and simulation system (20-Sim).

Design for Assembly Evaluation of Orientation Difficulty Features

In support of the effort to bring downstream issues to the attention of the designer as parts take shape, an analysis system is being built to extract certain features relevant to the assembly process, such as the dimension, shape, and symmetry of an object. These features can be applied to a model during the downstream process to evaluate handling and assemblability. In this paper, we will focus on the acquisition phase of the assembly process and employ a Design for Assembly (DFA) evaluation to quantify factors in this process. The capabilities of a non-homogeneous, non-manifold boundary representation geometric modeling system are used with an Index of Difficulty (ID) that represents the dexterity and time required to assemble a product. A series of algorithms based on the high-level abstractions of loop and link are developed to extract features that are difficult to orient, which is one of the DFA criteria. Examples for testing the robustness of the algorithms are given. Problems related to nearly symmetric outlines are also discussed.

A Knowledge Based Geometric Modeling System for Preliminary Design Using Object-Oriented Approach

A knowledge-based geometric modeling system for preliminary design was developed using object-oriented approach. Three types of knowledge for design, i.e. the model representing a design product including the geometric model, the procedures manipulating the design product and the knowledge managing the design process were integrated in the system. The model built up with object-oriented programming provides an effective and flexible design environment. Finally, the system was applied to the preliminary design of a ship’s hull arrangement to ascertain its validity and effectiveness.