Among a plurality of sensors that detect a state of a control subject, a relationship fluctuation level between a magnitude of a signal output by a subject sensor and a magnitude of a signal output by another related sensor is calculated for each subject sensor and related sensor combination. Moreover, the subject sensor and related sensor combinations for which a value of the relationship fluctuation level is a predetermined value or more are identified, and a respective number of appearances of the subject sensor and the related sensor included in the identified combinations thereof is calculated.

A method to ascertain a quality of a product formed by a subtractive manufacturing device from a workpiece includes: determining a deflection/test force relation for a deflection of the device; measuring an actually exerted machining force applied by the device to the workpiece; automatically determining a machining force reference for the actually exerted machining force; automatically evaluating whether the actually exerted machining force deviates from the machining force reference. If an actually exerted machining force deviates from the machining force reference, then the method uses the deflection/test force relation to automatically determine for the actually exerted machining force, at least one correction deflection of the device and automatically creating at least one corrected drive control signal to fully or partially reduce the correction deflection.

A system and method can identify manufactured parts. A user can select a particular manufactured part, which can be out-of-specification. The system can retrieve test data for the selected part and for other manufactured parts. The system can normalize the retrieved test data against historical means and historical standard deviations to form normalized test data. The system can correlate the normalized test data for the selected part against normalized test data for each of the other manufactured parts to form correlation values. The system can display the correlation values with identifiers corresponding to the manufactured parts. Each correlation value can represent a degree of similarity between the selected part and a respective manufactured part. The manufactured parts with the highest correlation values can have the same failure mechanism as the selected part, which can help diagnose why the selected part can be out-of-specification.

To visually display the manufacturing statuses of products manufactured through a plurality of manufacturing processes in order and changes of process characteristic factors caused in the manufacturing processes, a visualization system according to an embodiment stores manufacturing log information including start times and end times of manufacturing processes of products grouped in manufacturing units and manufactured through a plurality of manufacturing processes in order, and chronological history information of process characteristic factors corresponding to factors affecting quality characteristics in the manufacturing processes. A time axis for the process characteristic factors in synchronization with the time course of the manufacturing log information is created, and a display object representing a state or a change of each of the process characteristic factors is created based on the chronological history information and placed on the time axis to create a timeline object of each of the process characteristic factors. A process characteristic factor timeline screen including the timeline objects of the respective process characteristic factors arranged in parallel is displayed on a display apparatus.