Localization variation stream propagation modeling of multi-operation machining in IL&SM fixturing

The Initiative Locating and State Memory fixturing (IL&SM) adopts the technique of freezing workpiece in space, to realize the encapsulation, fastening and clamping in the IL&SM box. IL&SM technique is designed to “free-up” the design space and greatly expand the possible range of the parts that can be machined. It is clear that locating error is one of the factors that significantly contribute to workpiece quality in the early stage of machining. Source errors are categorized into IL&SM box and locators geometric default are systematically investigated to reveal their effects upon the workpiece machining error. Variation propagation modeling has been proved to be an effective way for variation reduction and design synthesis in multi-operational processes. A state space modeling approach is developed for the localization variation synthesis and control. It provides the basis for variation control through tolerance design analysis, synthesis, and diagnosis in manufacturing systems.