An apparatus for depositing a radius filler, made of a homogeneous material, into a groove, formed in a workpiece comprises a chassis, first means for extruding the radius filler along an extrusion axis, second means for providing the homogeneous material to the first means, and third means for compacting the radius filler in the groove. The apparatus also comprises a first sensor configured to provide first-sensor output. The apparatus further comprises a controller, operatively coupled to the first means, the second means, and the first sensor. Based on the first-sensor output, the controller is configured to determine the first geometric characteristics of the groove. In addition, based on the first geometric characteristics, the controller is configured to control second geometric characteristics of the radius filler, extruded by the first means, as the tool center point is moved relative to the groove.