Abstract: A mass production system for the manufacture of garments comprises a number of gantry robots which move shaped pieces of fabric over a work table between sewing and manipulating positions. In the sewing of scalloped lace to a garment, the sewing direction must always be parallel to the tangent to the undulating edge of the lace. The piece of lace is viewed by a camera, and the position of a notional datum line, such as a line passing through the minima of the undulations, is specified. Displacements of points along the edge of the lace are then determined relative to the datum line. Displacement and orientation values for guiding that particular piece of lace through a sewing position to produce a row of stitches at a constant distance inside the edge are calculated, and the piece of lace is subsequently guided through the sewing position in accordance with those values.