Variable speed signature collating apparatus

An apparatus (20) for forming sheet material assemblages comprises a conveyor assembly (22) having a plurality of locations (60) for receiving sheet material articles. A sheet material article feeder (54) feeds sheet material articles to the receiving locations (60) in the conveyor assembly (22). Each of the sheet material article feeders has an associated individual drive motor (86) for driving a sheet material feeder element, such as drum (93). A feeder sensor assembly (103) provides a signal indicative of the operative position of the feeder element or drum (93). A receiving location sensor assembly (59) provides a signal indicative of the position of a sheet material receiving location (60) approaching a sheet material article feeder. A sheet material feed controller (80) controls the sheet material feed element (93) in response to signals from the feeder sensor assembly (103), the receiving location sensor assembly (59), and a main controller (40).