Publications Details

A high resolution capacitive imaging sensor for manufacturing applications

Novak, J.L.; Wiczer, J.J.

A high-resolution capacitive image sensing technique for measuring edge and surface profiles during manufacturing processes has been invented. A prototype device utilizing this technique consists of two 500-μm-diameter electrodes fabricated on a printed circuit board with a 250-μm gap between them. As the device is mechanically scanned over the workpiece, the spatial variations in the edge or surface to be measured interfere with an electric field imposed between the electrodes, altering the mutual capacitance. The sensor functions as a near-field proximity sensor producing range images of surface imperfections. This sensor has been used in applications requiring a preview image of burns on the edge of a machined part and other processes requiring an inspection image after automated deburring operations.