THE APPLICATION OF THE CAPACITORS PHYSICS TO OPTIMIZE CAPACITIVE ANGULAR-POSITION SENSORS

The distributions of the potential and charge density in a capacitive angular-position sensor with three electrode disks in an axis-symmetri cal configuration have been found by creating a suitable physical mode l and solving Laplace's equation, The influences of geometrical parame ters on the nonlinearity, which originates from the electric-field-ben ding effect, are discussed in detail for a capacitive angular-position sensor, The approximately analytical results are verified by a numeri cal analysis and are found to be very useful to predict the influences of geometrical nonidealities, The calculations are experimentally ver ified by using a novel, absolute angular-position sensor with a nonlin earity of less than +/- 17'' and +/- 50'' over measurement ranges of 1 5 degrees and 90 degrees, respectively.