Patent ID: 8892396

Claim:
A method of determining a distance measure between a beginning and an end of a material strip wound onto a body in a tangential direction by a winding operation, comprising: creating, by a sensor device, a height profile of a surface of the material strip, which covers the beginning and the end of the wound material strip in the tangential direction; determining, by an evaluator, a position value of the beginning of the material strip in the created height profile; and determining, by a determiner, the distance measured by using the position value of the beginning and the height profile covering the end of the material strip, wherein the height profile is created during the winding operation, wherein height information associated with respective position values is determined and stored for a plurality of position values known or being equidistant in a tangential direction, wherein determining comprises extrapolating the position value of the beginning of the material strip to an extrapolated position value by adding a complete revolution of the body to the position value, performing an analysis of the position values only in a range surrounding the extrapolated position value in order to find a position value of the end of the material strip, so that the end of the material strip is logically distinguished from artifacts occurring outside of the range surrounding the extrapolated position value, and determining, as the distance measure, a tangential distance between the position value of the beginning of the material strip and the position value of the end of the material strip, wherein determining a position value of a starting or end edge comprises forming a derivative of the height profile, or, wherein a position value for a starting or end edge is determined if the value of the derivative of the height profile satisfies a threshold value criterion or lies within a predetermined interval, or wherein determining the position value of the beginning and/or the end comprises: determining a provisional position value of the beginning and/or the end for each of the measurement tracks of the 2-dimensional height profile; and determining the position value of the beginning and/or the end by combination of the provisional position value with the provisional position value of at least one of the measurement tracks immediately adjacent in the width direction; and wherein at least one of the sensor device, the evaluator, and the determiner comprises a hardware implementation.