Method for correcting a characteristic curve derived from a magnetoresistive sensor signal

US7295941B2 · kind B2 · utility

Assignee

• Leopold KOSTAL GmbH & Co. KG · DE

Inventors

• Oliver Maier · Worms, DE
• Christian Schirp · Bochum, DE
• Frank Blasing · Werl, DE

Key dates

• Filing date: Dec 30, 2005
• Grant date: Nov 13, 2007
• Expiry date: Jul 15, 2026

Classification

• Technology area (CPC G): Physics
• CPC primary: G01D18/001
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A method for correcting a characteristic curve having values corresponding to displacement between a magnetic sensor element and a magnetic ruler of a sensor within a displacement range includes determining whether the characteristic curve has a jump discontinuity by comparing a first value at a first range end to a second value at a second range end and by comparing values between the range ends. Upon determining that the characteristic curve has a jump discontinuity, the method further includes determining the magnitude of the jump discontinuity, defining a decision threshold lying between the first and second values, identifying the values within the range which are lower than the decision threshold, and offsetting the identified values by the magnitude of the jump discontinuity such that the characteristic curve is corrected to eliminate the jump discontinuity, whereby subsequent measurements made by the MR sensor take into account the jump discontinuity magnitude offset.