METHOD FOR SELF-CALIBRATING A TORSION ANGLE DETECTED BY A TORQUE/ANGLE SENSOR

The invention relates to method for self-calibrating a torsion angle detected by a torque/angle sensor, according to which two code wheels (1a, 1b) with an interposed torsion element (9) are mounted on a shaft (3). The two code wheels (1a, 1b) are associated with sensor elements (5) that detect the codes (2) of the code wheels (1a, 1b) according to a angle of rotation of the shaft (3) and that transmit electrical signals to an evaluation unit (10). In a calibration step, a predetermined number of angle measurements is carried out, every code wheel measuring the angle of rotation during every measurement as precisely as possible. The individual pairs of angles are averaged and stored in the evaluation unit (10) with their differential value (the angle-dependent torsion angle error). This process is carried out when no torque (M) is applied to the shaft (3). During later operation, when a torque (M) acts on the shaft (3), such as is the case in a steering shaft of a motor vehicle, the respective new torsion angle is measured by both code wheels (1a or 1b) and corrected with the pertaining stored torsion angle error.