Concurrent fixture design for automated manufacturing process planning

摘要

In computer-aided manufacturing process planning, the determination of fixtures is often completed after a process plan is generated. This strategy does not consider the manufacturing dependency between the process planning and the fixture design, which in fact needs to be thoroughly assessed before any conclusion regarding the optimality of a plan or the quality of a proposed fixture can be made. In this paper, a concurrent approach is presented in which the fixture design and machine planning are combined in an automated search process that starts with simply a CAD model. First, a rule-based algorithm is used to define all feasible manufacturing operations for the given CAD model. Then, a hierarchical search technique is developed to discern which operations are best in terms of manufacturing time, cost, and fixture quality. The fixture quality is a quantitative measure derived based on a collection of fixture design guidelines from manufacturing experiences and engineering handbooks and is intended to give a consistent and complete assessment of a fixture design. Cases studies and discussion are provided to showcase distinct characteristics of our algorithm. A real implementation of one suggested plan is also presented in order to validate the effectiveness and practicality of our approach.