Identification of functional components in mechanical assemblies

Manufactured products with different purposes often include similar mechanisms to realize movements required to satisfy specific functionalities. An automatic identification of common mechanisms in assembly models would be a valuable support for analysing or reusing exiting solutions during the design process. In this paper, we present a first step towards the identification of mechanism for motion transformation, focusing on those containing non-linear bearings. In particular, we describe methods for non-linear bearing identification within assemblies, which allow axial rotation, as a shaft rotation. The main novelty concerns the capability of detecting bearings independently on their design level of details, i.e. represented as assemblies of their constituent components or idealized by their external 3D shape outline. The proposed method is based on a set of rules defined according to a priori knowledge and exploits implicit information automatically extracted from the assembly description and can be extended to other types of mechanism

Feature Cluster Algebra and Its Application for Geometric Tolerancing

abstract: The goal of this research project is to develop a DOF (degree of freedom) algebra for entity clusters to support tolerance specification, validation, and tolerance automation. This representation is required to capture the relation between geometric entities, metric constraints and tolerance specification. This research project is a part of an on-going project on creating a bi-level model of GD&T; (Geometric Dimensioning and Tolerancing). This thesis presents the systematic derivation of degree of freedoms of entity clusters corresponding to tolerance classes. The clusters can be datum reference frames (DRFs) or targets. A binary vector representation of degree of freedom and operations for combining them are proposed. An algebraic method is developed by using DOF representation. The ASME Y14.5.1 companion to the Geometric Dimensioning and Tolerancing (GD&T;) standard gives an exhaustive tabulation of active and invariant degrees of freedom (DOF) for Datum Reference Frames (DRF). This algebra is validated by checking it against all cases in the Y14.5.1 tabulation. This algebra allows the derivation of the general rules for tolerance specification and validation. A computer tool is implemented to support GD&T; specification and validation. The computer implementation outputs the geometric and tolerance information in the form of a CTF (Constraint-Tolerance-Feature) file which can be used for tolerance stack analysis.Dissertation/ThesisM.S. Mechanical Engineering 201

PROJECTIVE CONVEXITY IN COMPUTATIONAL KINEMATIC GEOMETRY

ABSTRACT In recent years, there is an increasing interest in developing geometric algorithms for kinematic computations. The aim of this paper is to present the notion of projective convexity as a key element for a new framework for kinematic geometry, that allows for the development of more elegant and efficient algorithms for geometric computations with kinematic applications. The resulting framework, called computational kinematic geometry, is developed by combining the oriented projective geometry with the kinematic geometry of rigid body motions

3D analysis of tooth surfaces to aid accurate brace placement

Master'sMASTER OF ENGINEERIN

Proceedings of the International Workshop "Innovation Information Technologies: Theory and Practice": Dresden, Germany, September 06-10.2010

This International Workshop is a high quality seminar providing a forum for the exchange of scientific achievements between research communities of different universities and research institutes in the area of innovation information technologies. It is a continuation of the Russian-German Workshops that have been organized by the universities in Dresden, Karlsruhe and Ufa before. The workshop was arranged in 9 sessions covering the major topics: Modern Trends in Information Technology, Knowledge Based Systems and Semantic Modelling, Software Technology and High Performance Computing, Geo-Information Systems and Virtual Reality, System and Process Engineering, Process Control and Management and Corporate Information Systems