Etude preliminaire de l'utilisation de la realite virtuelle pour l'analyse de tolerance

In today's trend towards globalization, companies are subcontracting an increasing amount of their workload. It is of primary importance to ensure that the components manufactured in different places will assemble. The geometrical and dimensional tolerances on the detail drawing indicate the quality standards of a part. However, the cost of manufacturing is proportional to the requested precision level. A high degree of accuracy for machining makes it possible to minimize the rejections of parts that would result from non-assemblability and other quality problems, but the manufacturing costs are higher. Large tolerances can reduce the manufacturing costs, but will decrease the overall quality. Tools to carry out the analysis of the tolerances make it possible to optimize the tolerances.;The first objective of this research was to define a new graphical method of resolution and demonstrate its concept in a virtual reality environment. The second objective was to ensure that any type of tolerance could be included in the analysis.;The first objective is met through the development of a prototype application which uses a 3D graphical method to perform tolerance analysis in a virtual reality environment. This demonstrates the feasibility of the approach and recommendations are proposed to enhance the application. The use of virtual reality is justified because it makes it possible to better seize the impact of the tolerances. For the second objective, a C++ library has been developed to do the interpretation of the tolerances. This tool makes it possible to generate the kinematic loops of a control function and identify the tolerances that affect any topological element in the loop.;The aim of this research is to solve the problem of tolerance analysis which is difficult to conceptualize. The analysis of the geometrical and dimensional tolerances is divided into two main tasks: (1) the interpretation of the tolerances to capture the meaning of the tolerances and obtain the kinematics loops of the control function and; (2) a method of resolution in order to quantify the size of the gaps or interference.