Process planning automation based on the dynamic manipulation of form features.

The importance of the process planning automation is well understood, and many CAPP systems using expert system techniques have been constructed. For this process planning automation, form features, which are technological characteristics of the shape, have the most important meanings. Most of the current CAPP systems lack the ability of manipulating this form feature, it is difficult for them to consider the effect of machining operation in process planning. To solve this problem, a form feature modeling system is developed and incorporated in our process planning system XMAPP. XMAPP represents and uses process planning methods and constraints in the form of production rules. Those rules not only refer to the form feature information, but also dynamically manipulate them as needed in the process of problem solving. By using this form feature modeling function, a blank material product model is automatically generated based on a given machine part model. A machining operation plan is also obtained by recording this modeling process properly.