초록 ▼

A vehicle compass includes a magnetic field sensor for mounting within a vehicle and providing two output channels of information representing orthogonal direction sensing of the earth\s magnetic field within the vehicle. The sensor is coupled to an electrical circuit including a microprocessor for

A vehicle compass includes a magnetic field sensor for mounting within a vehicle and providing two output channels of information representing orthogonal direction sensing of the earth\s magnetic field within the vehicle. The sensor is coupled to an electrical circuit including a microprocessor for sampling the data from each of the two channels and providing a plurality of tests to determine if the rate of change of data is within a prescribed limit thereby indicating valid data is being received. Further, the data is tested to determine the maximum and minimum signal levels during movement of the vehicle through a completed 360°path of travel and for calculating therefrom the compass compensation information used to provide a corrected heading display.

대표청구항 ▼

In an electronic compass system for use in a vehicle such as an automobile comprising: sensing means for detecting the earth\s magnetic field and for providing electrical signals representative of the direction of movement of the vehicle with respect to the earth\s magnetic field; circuit means coup

In an electronic compass system for use in a vehicle such as an automobile comprising: sensing means for detecting the earth\s magnetic field and for providing electrical signals representative of the direction of movement of the vehicle with respect to the earth\s magnetic field; circuit means coupled to said sensing means for providing display output signals representing heading information corresponding to the detected direction; display means coupled to said circuit means for displaying the vehicle heading in response to said display output signals, wherein the improvement comprises: said circuit means including means responsive to the direction representative signals for detecting the rate of change of said direction representative signals, and for determining if the rate of change exceeds a predetermined level thereby indicating the existence of invalid detected direction information; and means for providing an error output signal for display in response to said determining means determining that said rate of change exceeds said predetermined level.