Patent ID: 10876864

Abstract:
A high resolution encoder device using a number of static sensors distributed on a circumference, and a rotating disc, having several sections of two different properties on an annular track according to a predefined pattern, placed so that the sensors can sense the properties of the sections of track in proximity. An auxiliary unit is also provided and by itself or in combination with the sensor signal values, provides a first low resolution position value. In a first processing step, the signals of each sensor are compared to a threshold, and bit values zero or one for each sensor are set according to the comparison result. All bits are then set in a digital word, in order to create a code number, which in combination with the output of the auxiliary unit, is characteristic of a first low resolution position value. For each low resolution position value, a mathematical combination of signals values is defined. The values of the result of said mathematical combination of the signals value is then used as an entry variable to pre-recorded tables to output high resolution position value.