Decoupling of Scan Period and Control Period for Sheet Process Control Systems Employing a Scanning Gauge

This paper is concerned with the development of a simple technique for decoupling the measurements of machine direction (MD) and cross machine direction (CD) variations in sheet process production systems employing a single scanning gauge. An important consequence of the method is that machine direction control can be exercised at a much higher rate than is possible with current methods of separating MD from CD. This, in turn, can mean a significant improvement in MD control performance since the range of MD disturbances a given control system is capable of suppressing is increased.