Abstract: An imaging system includes an imaging station, an actuator for driving a medium roller for controllably displacing the medium along a media transport path, and a controller assembly. The controller assembly includes a sensor device for generating a position signal and a processor for processing the position signal. The actuator is actuated in response to an actuation command from the controller assembly, which actuation command is derivable from a feedback component and a feedforward component. The feedback component is based on a position error. The processor is further arranged for determining a time dependent status parameter, which status parameter represents a status of the medium on the medium roller. The processor is further arranged for deriving an actuation command estimate based on the status parameter, and wherein the feedforward component includes the actuation command estimate.

Abstract: An imaging system includes an imaging station, an actuator for driving a medium roller for controllably displacing the medium along a media transport path, and a controller assembly. The controller assembly includes a sensor device for generating a position signal and a processor for processing the position signal. The actuator is actuated in response to an actuation command from the controller assembly, which actuation command is derivable from a feedback component and a feedforward component. The feedback component is based on a position error. The processor is further arranged for determining a time dependent status parameter, which status parameter represents a status of the medium on the medium roller. The processor is further arranged for deriving an actuation command estimate based on the status parameter, and wherein the feedforward component includes the actuation command estimate.

Abstract: In a printer having a print head moveable relative to a recording medium, the recording medium and print head may touch each other, thereby possibly damaging the print head and/or the recording medium. In order to prevent further damage, it is advantageous to detect a medium touch as soon as possible. An available feedback signal relating to the print head, e.g. originating from a carriage on which the print head is mounted, is employed to determine whether a medium touch has occurred such that a dedicated medium touch or crash sensor may be omitted. A malfunctioning nozzle signal is used to determine a change in a number of malfunctioning nozzles to detect a medium touch. Alternatively, a print head position signal is used to determine a position error and derive from the position error whether or not a medium touch has occurred.

Abstract: An imaging system for processing a media includes a media transport path, an imaging station, a displacement device that controllably displaces the media along the media transport path relative to the imaging station, and a controller assembly. The controller assembly includes a feedback filter, a feedforward filter, a low-pass filter and a memory that stores and time delayed releases control data. During operation, the displacement device is actuated in response to an actuation command generated by the controller assembly. The actuation command has a feedback component based on a filtering by the feedback filter of an error signal including information about the position error between a desired and an actual position of the media and a feedforward component based on a time delayed, low-pass filtered, frequency dependent filtering of the error signal by the feedforward filter. The feedforward filter is configured such that the closed-loop controlled characteristics of the displacement device are compensated.

Abstract: An imaging system for processing a media includes a media transport path, an imaging station, a displacement device that controllably displaces the media along the media transport path relative to the imaging station, and a controller assembly. The controller assembly includes a feedback filter, a feedforward filter, a low-pass filter and a memory that stores and time delayed releases control data. During operation, the displacement device is actuated in response to an actuation command generated by the controller assembly. The actuation command has a feedback component based on a filtering by the feedback filter of an error signal including information about the position error between a desired and an actual position of the media and a feedforward component based on a time delayed, low-pass filtered, frequency dependent filtering of the error signal by the feedforward filter. The feedforward filter is configured such that the closed-loop controlled characteristics of the displacement device are compensated.

Abstract: In a printer having a print head moveable relative to a recording medium, the recording medium and print head may touch each other, thereby possibly damaging the print head and/or the recording medium. In order to prevent further damage, it is advantageous to detect a medium touch as soon as possible. An available feedback signal relating to the print head, e.g. originating from a carriage on which the print head is mounted, is employed to determine whether a medium touch has occurred such that a dedicated medium touch or crash sensor may be omitted. A malfunctioning nozzle signal is used to determine a change in a number of malfunctioning nozzles to detect a medium touch. Alternatively, a print head position signal is used to determine a position error and derive from the position error whether or not a medium touch has occurred.