Diagnosis of multiple fixture faults in machining processes using designated component analysis

Fixture imperfections influence dimensional variation on machining processes. Therefore, a systematic method to isolate fixture faults will allow improvement in product quality. This paper presents a diagnosis methodology to identify root causes of fixture-induced workpiece variation in machining. The methodology is based on designated component analysis, which extracts predefined variation patterns from the production data. The methodology integrates online measurement data, part geometry, fixture layout, and sensor layout in detecting multiple fixture faults occurring simultaneously. An application of the proposed method is presented through a computer simulation.