Patent ID: 7319303
Filing Date: 2008-01-15
Classification: G01B,G01D

Abstract:
1. A method for estimating the position of a moving part of a linear actuator, comprising: (a) moving the moving part of the linear actuator towards a target position; (b) receiving magnetic signals of an MR sensor of the linear actuator, the magnetic signals including a sine signal and a cosine signal; (c) generating a first square wave, a second square wave, and a regional square wave based on the sine signal and the cosine signal; (d) generating a saw-tooth wave based on the sine signal, the cosine signal, the second square wave, and the regional square wave; (e) calculating a distance between the moving part and an origin point of a sliding track based on the first square wave, the second square wave, and the regional square wave, wherein the moving part is mounted on the sliding track and the distance is measured in a number of regions of the saw-tooth wave; and (f) estimating a current position of the moving part based on the saw-tooth wave and the number of regions.