Techniques for robust endless belt tracking control

摘要

A belt tracking system for an endless belt having left and right opposed edges, the belt driven in a first direction by a belt drive system. The tracking system includes a set of periodic belt indicia formed on the belt along one or more axes aligned with the first direction. A sensor system tracks movement of the belt in a lateral direction transverse to the first direction and senses the set of belt indicia to provide sensor system signals. An actuator system effects movement of the belt in the lateral direction, the actuator system responsive to the sensor system signals for nominally maintaining a position of the belt relative to the transverse direction. A controller is responsive to the sensor system signals for detecting that the belt has tracked outside an allowable belt movement range and taking protective actions to prevent the belt from damage due to undesired lateral tracking movement. A belt indicia sensor can optionally be employed to calibrate a belt drive system.