سیستم برنامه ریزی عملیات بازرسی مبتنی بر ویژگی برای هماهنگ دستگاه اندازه گیری (CMM)

This paper outlined a feature-based inspection process planning system for co-ordinate measuring machines (CMMs). The inspection process planning system is designed to produce an inspection process planning directly from CAD model. The prototype inspection process planning system includes five functional modules: the tolerance feature analysis, accessibility analysis, clustering algorithm, path generation and inspection process simulation. The tolerance feature analysis module is used to input tolerance information and establish the relationship between the tolerance information and surface feature. The accessibility analysis module evaluate all the accessible probe orientations for every surface feature. The clustering algorithm module groups the inspection probe and surface features into inspection group so that time for inspection probe exchange and calibration can be reduced to minimum. The path generation module determines the number of measurement points, their distribution and their inspection sequences. The inspection process simulation module animated display the inspection probe path and check whether a collision occurs between the part and the inspection probe. The methodology and theory for corresponding five functional modules are outlined. An example demonstrate the general process for the application of the inspection process planning system. The prototype inspection process planing system shown that the proposed theory and methods can be used in industry to generate an inspection process planning for a CMM.

Recently, researches in inspection process planning have been increased [1]. Some prototypes inspection process planning systems have been developed. These systems include the task-decomposition inspection process planning system [2], [3], [4], [5] and [11], the knowledge-based inspection process planning system [6] and [10] and some hybrid inspection process planning systems [7], [8] and [9]. However, these systems are not satisfied by the industry. This paper outlined a prototype inspection process planning system. The inspection process planning system can be used to generate an inspection process planning for a CMM. It can be used as an integrated system starting from solid model and finishing at production of inspection process planning file. However, it can also be used as five stand alone function modules for the tolerance feature decomposition, accessibility analysis, clustering algorithm, path generation and the inspection process simulation, respectively. The inspection process planning system can be linked to a CAD system so that an inspection process planning can be produced directly once a part design has been finished. It is expected that the laborious and error-prone manual programming currently used for a CMM can be replaced with the developed inspection process planning system. The lead-time for the CMM programming can be reduced significantly.

The methodologies developed in the research project for the tolerance feature analysis, accessibility analysis, clustering algorithm, path generation and inspection process simulation are tested and a prototype of inspection process planning system that includes corresponding five functional modules about these techniques have been built up. The time for evaluating a probe orientation is thus reduced significantly due to the application of the developed accessibility analysis module. Two methods of adjacent matrix representations are used to represent the relationships between the probe orientations and the surface features. The knowledge-based clustering algorithm provides a methodology to produce a partial separated block diagonal matrix when a block diagonal matrix does not exist. A comprehensive example about the application of the developed system for a test component is provided and it is confirmed that all the functional modules work properly and the prototype of inspection process planning system can be used as an aid for the inspection process planning.