A self-calibration technique for a smart capacitive angular-position sensor

A novel piecewise calibration technique for capacitive position sensors, based on the use of a microcontroller is presented. This technique offers a good trade-off between the memory size of the microcontroller and the algorithmic complexity. The application of this technique for self-calibration of the inaccuracy caused by the mechanical errors and pattern errors in a capacitive angular-position sensor is discussed. This self-calibration technique doesn't need any accurate reference. Experimental results show that the piecewise self-calibration is relatively effective in reducing the influences of the mechanical errors and pattern errors of the sensor. The reduction of the inaccuracy of the sensor amounts to more than a factor of two.