Components of a design object are graphically displayed on a display device of an apparatus for making a design reference. A designated interference check element graphically displayed on the display device imitates an article or human being moving in an area in which an actual design object is arranged....http://www.google.com.au/patents/US5006991?utm_source=gb-gplus-sharePatent US5006991 - Method for making of design reference and apparatus therefor
