Method and device for determining absolute angular position of a rotating body

摘要

A method and device for determining the absolute angular position of a rotating body includes an input gear attached to a rotating body and meshed with a single output gear. The gear ratio between the input gear and the output gear is a non-integer, so that the output gear will be out of phase with the input gear as the input gear completes successive revolutions. A sensor is placed in close proximity to the output gear and provides a signal to a microprocessor representing the angular position of the output gear. This signal is used by the microprocessor to calculate the absolute angular position of the input gear and thus, the absolute position of the attached rotating body.