Selective assembly method for mechanical product with multi-objective assembly function

Aiming at the selective assembly problem for mechanical product with multi-objective assembly function, a method based on strong-weak Pareto and genetic algorithm was proposed. An unified selective assembly information model oriented to 3D space was established based on the analysis of mechanical product's assembly characteristics, with which a comprehensive optimization model taking the assembly precision and assembly yield into consideration was constructed. A coding method taking tolerance item as unit was used and a comprehensive evaluation rule describing important relationship between assembly functions by concepts of strong-weak Pareto and crowed degree based on weighting coefficient was put forward. By considering the order of measured data from different tolerance items, a multi-objective genetic algorithm under the rule of comprehensive evaluation was used to achieve the high efficiency and best match solution in the process of selective assembly. A prototype system was developed and an example was tested to verify the feasibility of proposed approach.