Propositions of numerical solution techniques for the tolerance analysis problem in manufacturing: 3D approach
This research contributes to developing the solution techniques associated with the MMP (Model of manufactured part) simulation method developed by F.Villeneuve and F.Vignat for modeling the different geometrical deviation impacts on the part produced (error stack-up) in a multi-stage machining process. The model cumulates the impacts of various sources of manufacturing errors hence enabling tolerance analysis. The MMP simulation method beside the developed solution techniques allows the manufacturing engineers to evaluate a candidate process plan from a geometrical point of view. The developed solution techniques are classified into two categories: Search for finding the worst case (worst part produced) and stochastic method. The first approach of the first category uses the optimization algorithms to search for the worst case. A multi-layer optimization algorithm is developed in order to search for the worst case. The performance of two current optimization methods for worst case identification using this algorithm (genetic algorithm and sequential quadratic programming) has been studied. The second approach of the first category uses a combined solution technique which is built on the Canadian Jacobian torsor model and the French MMP model for tolerance analysis. This method uses the interval arithmetic. The second category consists in stochastic method which allows simulating a very large sample of production and analyzing the results from a statistical point of view. This method uses Monte Carlo simulation with a constrained random generator. The performance of the developed solution techniques is compared through 3D examples.
PhD Student: Mojtaba KAMALINEJAB Grenoble University, 2006 Director: François VILLENEUVE