Method and device for determining a recognition threshold

US9500465B2 · kind B2 · utility

Assignee

• Robert Bosch GmbH · DE

Inventors

• Eduard Rolew · Leonberg, DE
• Verena Schmidt · Erbendorf, DE
• Bernhard Opitz · Leonberg, DE

Key dates

• Filing date: Oct 31, 2011
• Grant date: Nov 22, 2016
• Expiry date: Jun 14, 2033

Classification

• Technology area (CPC G): Physics
• CPC primary: G01D5/145
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A method for determining a recognition threshold for recognizing the presence of a tooth or a tooth gap of a position sensor in front of a sensor is presented. The method includes a step of reading in a sensor signal which represents a variation over time of a measured magnetic field when the teeth and the tooth gaps of the position sensor are passed by the sensor. In addition, the method includes a step of ascertaining from the sensor signal a first value based on a minimum value of the sensor signal and a first value based on a maximum value of the sensor signal within a predefined time interval. The method also includes a step of computing a differential absolute value which represents a predetermined percentage of a difference between the value based on the at least one maximum value and a value based on the at least one minimum value of the sensor signal. Lastly, the method includes a step of determining the recognition threshold, so that the recognition threshold represents a value that corresponds to a result of adding the differential absolute value to the first value based on the minimum value of the sensor signal.