Method of automatic continuous calibration for an electronic compass

摘要

An autocalibration method for use within an electronic compass in a vehicle is disclosed. The method includes steps of initializing variables and then retrieving sensor readings from at least two axis. The method then compares the compass tilt to a predetermined threshold. Next the method will determine if the sensor reading is a minimum or maximum for the current calibration cycle. Next the method will determine if the maximum value of the sensor readings is greater than the predetermined minimum spread. Then the method will calculate an offset value for each axis and calculate a sensor value for each axis. Then the method will calculate an azimuth value with the new sensor values and determine the heading using the azimuth.