Abstract: Methods and control systems are provided for controlling stage position errors based, in some embodiments, on a selection of frequency components in a stage position error signal. An error frequency representation of a position error signal may be generated in the frequency domain and filtered by selecting one or more desired frequency components. The filtered error frequency representation can then be manipulated according to a control law and transformed back into the time domain to generate a current control signal. The current control signal can then be used to adjust the position of the stage to reduce positioning error.

Abstract: Methods and control systems are provided for controlling stage position errors based, in some embodiments, on a selection of frequency components in a stage position error signal. An error frequency representation of a position error signal may be generated in the frequency domain and filtered by selecting one or more desired frequency components. The filtered error frequency representation can then be manipulated according to a control law and transformed back into the time domain to generate a current control signal. The current control signal can then be used to adjust the position of the stage to reduce positioning error.

Abstract: A system and method for tracking belts disposed on rollers in a photoreceptor apparatus. The system includes a movable, belt edge guide that operates in combination with an encoder, a belt edge sensor, a belt hole sensor for detecting a hole in the belt surface, wherein the profile of the edge of the belt is learned as a function of the belt position on the rollers. The encoder and belt hole sensor are used to actuate the edge guide system to compensate for the contours of the belt edge and to maintain a constant lateral position of the belt at any given point on the belt.

Abstract: A system and method for tracking belts disposed on rollers in a photoreceptor apparatus. The system includes a movable, belt edge guide that operates in combination with an encoder, a belt edge sensor, a belt hole sensor for detecting a hole in the belt surface, wherein the profile of the edge of the belt is learned as a function of the belt position on the rollers. The encoder and belt hole sensor are used to actuate the edge guide system to compensate for the contours of the belt edge and to maintain a constant lateral position of the belt at any given point on the belt.

Abstract: An apparatus for controlling velocity variations in a belt wrapped about at least a first driven roller and a support structure, including a drive for driving the first driven roller so as to provide torque to the belt; and a dampener, in contact with the belt, for minimizing variations of the velocity of the belt, the dampener including a power supply for applying an electrical bias to generate a drag force on the belt.

Abstract: A closed loop control system precisely sets and monitors tension in a photoreceptor belt. A stepper motor is actuated by a controller to apply pressure to a yoke connected to the photoreceptor belt through a steering roll. A strain gauge positioned on the yoke senses the pressure of the yoke against the photoreceptor belt and signals the controller which in turn actuates the stepper motor to bring the tension on the belt to a predetermined set amount. The closed loop control system also increases tension on the photoreceptor belt to improve drive capacity if friction between the photoreceptor belt and a drive roll decreases during operation as sensed by a decrease in driver motor torque.