Flyer determination and elimination for side edge electronic registration

A printing apparatus, comprising:

• a marking device, the marking device being capable of placing an image on a sheet fed therein, and outputting the sheet;
• a feed path, by which sheets are fed from a sheet supply to the marking device;
• a duplex path, by which sheets output from the marking device are re-fed to the marking device;
• a first sensor, outputting a first position signal relating to a location of a side edge as each sheet passes through the feed path;
• a second sensor, outputting a second position signal relating to a location of a side edge as each sheet passes through the duplex path;
• and
• an image placement controller associated with the marking device, the image placement controller retaining first position signals for a plurality of sheets passing through the feed path and second position signals for a plurality of sheets passing through the duplex path, and calculating new average paper positions for each sheet in response to at least one of the first position signals and the second position signals.

A method for determining and eliminating flyers in a printing apparatus, comprising:

• measuring each sheet position at a first sensor, wherein the first sensor outputs first position signal to a controller;
• determining sheet position and sheet variance based on first position signal;
• comparing sheet variance to a running average sheet variance to determine whether the sheet is a flyer;
• and
• calculating new average sheet position based on said comparison for marking images on sheets.