METHOD AND DEVICE FOR CORRECTING SYSTEMATIC TRACK SIGNAL ERRORS OF INCREMENTAL POSITION OR ANGLE OF ROTATION SENSORS

摘要

The invention relates to a method for correcting systematic track signal errors of incremental position or angle of rotation sensors which generate at least two, approximately sinusoidal track signals which have the same period and which are off-set by a phase angle. Said method comprises the following steps: a) detecting the track signal values (xk, yk) in the current measuring cycle (k); b) correcting the detected track signal values (xk, yk) using a stored error correction value (GPP-1), thereby obtaining corrected track signal values (xk', yk'); c) transforming the corrected track signal values (xk', yk') to give polar coordinate values (rk; ϕk); d) producing an error radius (rek); e) weighting said error radius (rek) with an evaluation variable (wk), thereby obtaining a weighted error variable (uk); f) producing an angular difference (Δϕk) from the angle (ϕk) obtained by transformation and an angle (ϕk-1) obtained and stored in the preceding measuring cycle (k-1); g) multiplying the weighted error variable (uk) by the angular difference (Δϕk), thereby obtaining an area value (Fk); h) adding up the determined area value (Fk) and a cumulative area value (FSk-1) stored in a proceeding measuring cycle (k-1), thereby producing a new cumulative area value (FS k); i) storing the new cumulative area value (FS k) and the angle (ϕk); k) repeating steps a) to i) until a correction interval (P) comprising one ore more periods of the track signals has passed; l) storing the cumulative area value (FS k) at the end of the correction interval (P) as the new error correction value (Gp).