A first characteristic portion of a first workpiece and a second characteristic portion of a second workpiece are previously determined. A characteristic amount detection unit detects a first characteristic amount related to the position of the first characteristic portion and a second characteristic amount related to the position of the second characteristic portion in an image captured by a camera. A calculation unit calculates, as a relative position amount, the difference between the first characteristic amount and the second characteristic amount. A command generation unit generates a movement command for operating a robot based on a relative position amount in the image captured by the camera and a relative position amount in a predetermined reference image.

Manufacturing of a shoe is enhanced by creating 3-D models of shoe parts. For example, a laser beam may be projected onto a shoe-part surface, such that a projected laser line appears on the shoe part. An image of the projected laser line may be analyzed to determine coordinate information, which may be converted into geometric coordinate values usable to create a 3-D model of the shoe part. Once a 3-D model is known and is converted to a coordinate system recognized by shoe-manufacturing tools, certain manufacturing steps may be automated.