Karl Mayer's computer aided design (CAD) pattern development system designs pile fabrics for office chairs, automobile upholstery, and seat components. The pattern development system comprises a computer, a video display unit, a keyboard, a mouse, and a printer. The CAD system is used in conjunction with the double bar RD 7 DPLM-EL raschel machine. The seven bar raschel machine has four ground and three pile bars, which are electronically controlled.