Automatic calibration of sinusoidal encoder signals
Abstract
Precision positioning and manipulation systems often rely on data fromsensors delivering a sinusoidal signal pair. These signals can be interpolatedto provide a high resolution measurement. The paper presentsa novel method for removing signal differences and drifts byautomatic self-calibrating the sinusoidal signal pair.Then, manual calibration is avoided and slow varying effects,like thermal drifts or unprecise sensor mounting, can be effectivelycompensated.The proposed method can be implemented on a DSP.It uses an on-line gradient search to minimize a givenperformance index.
