Non-traditional tolerance design techniques for low machining cost

In order to have a competitive edge, manufacturing companies have to develop superior quality products at minimum cost. Tolerance design is the most critical part of concurrent engineering in which optimal values of tolerances have to be determined for all components of an assembly, with due consideration towards the cost as well as quality. In this paper, tolerance design optimization of two products namely piston - cylinder & punch die assembly are considered. To solve the constraint-based optimization problems which are nonlinear and multi-objective in nature, novel techniques like Particle Swarm Optimization (PSO), and the Non Dominated Sorting Genetic algorithm II (NSGA II) have been used. The results of the piston-cylinder assembly have been compared to those of complicated and evolutionary techniques like Simulated (SA) and Genetic Algorithms (GA). In addition, their performances have been examined.