State estimation from incremental sensor data corrupted by track miscounts and a detection delay

Abstract

This paper presents a pragmatic algorithm for accurate velocity and position estimation from incremental position signal in the presence of track miscounts and a detection dead time. One specific application of this algorithm is accurate velocity estimation and position correction in an optical disk drive. This paper, however, is written to suit other systems using an incremental sensor where a miscount and/or a detection dead time cause severe problems in position and/or velocity control. This estimator consists of a conventional Kalman filter and a function block to correct a miscount and a detection delay. Both the structure and the algorithm of this function block are relatively simple. Two simulation examples based on a simplified model of a commercial optical disk drive are given to show the effectiveness of the present estimator in correcting track miscounts and a detection delay.