Based on the rapid advancement of IoT technology, it has become pervasive in various industries for promoting effective production, including the plastic injection molding industry. In this study, a fundamental investigation of mold deformation was conducted to develop a monitoring system. Mahalanobis distance (MD), which is calculated from mold strain data, was adopted in this monitoring system. We determined that the simple MD index is helpful for judging between normal and abnormal mold states. This index is expected to be a key component of future IoT applications.

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