Sensor Based Monitoring for Real-Time Quality Control in Manufacturing

This paper describes sensor-based methodologies for novel real-time quality control strategy in manufacturing. Feasibility of the methodology is demonstrated in two manufacturing processes: turning and powder injection molding. In case of turning, the process is monitored using force and vibration sensors. The level of tool wear on the cut-ting tool is estimated using the information from these sensors. The quality of workpiece is main-tained by adjusting the operating conditions and cutting tool position to compensate for the undesir-able effects of the progressive tool wear. In case of powder injection molding, the product quality fac-tors are obtained by visual inspection and process states are abstracted from the sensor data. The diagnostic knowledge is represented by a causality network and solved by network conversion method and abductive reasoning. The diagnostic solution provides a set of alternative hypothesis of disorders which explains the manifested quality factors and process states. 1