電容式感測器是一種將待測物理量變化轉換成電容變化量的器件，具有 體積小，功耗低，靈敏度高等優點，常用的形式是由兩個平行電極組成。本論文利用電容特性開發一液體汙濁度感測器，用於放電加工機加工液體量測。本研究成功開發一感測器，量測加工液體中介電物質如氧化鋁與矽粉末之濃度，量測濃度範圍由 5 g/100 ml 至 50 g/100 ml，且成功量測鐵粉、碳粉等導電粒子在加工液中之濃度，最低鐵粉量測濃度為 1.2 g/100 ml，而碳粉最低量測濃度為 0.25 g/100 ml。除了感測液體濃度，本論文亦開發智慧型感測藍芽傳輸功能，將感測數據傳輸雲端進行大數據儲存進而提升感測器價值。;Capacitive sensor is a device that convert the physical variation into capacitance variation, which has the advantages of small volume, low power consumption and high sensitivity. The common structure is composed of two parallel conductive plane. In this paper, we utilized the characteristics of capacitance to develop a liquid pollution sensor for electrical discharge machining liquid measurement. In conclusion, we successfully measured dielectric materials such as alumina and silicon powder, and the measured concentration range is 5 g/100 ml to 50 g/100 ml. Also, we successfully measure iron powder and carbon powder, and the minimum of iron powder concentration is 1.2 g/100 ml, while the minimum of carbon powder concentration is 0.25 g / 100 ml. In addition to the concentration sensor of liquid, this paper also developed intelligent Bluetooth transmission function. The sensing data will be transmitted to the clouds for the storage of big data and enhance the value of the sensor.
