The paper presents a new approach to the problem of nesting of plane parts. The system developed is tailored for nesting of production parts for shipyards, more specifically those prepared by the AUTOKON 71/74 system. However, the general design is believed to be independent of any particular part-coding system or application. Geometrically, the problem of nesting is a two-dimensional one, and it is basically similar to any jigsaw puzzle or two-dimensional cutting-stock problem if one disregards all the application considerations that constrain the solution. The programs developed do not attempt any automatic optimization. The philosophy in designing the system has been that the user is capable of optimizing whatever his objective is, if only the computer is able to supply the appropriate information. Defining and applying the constraints required to do automatic nesting not only becomes difficult, it becomes impossible as constraints on the parts layout change dynamically. The system was developed and is, so far, implemented minicomputers NORD-10 and SM-4. The graphics display on the Norwegian used is a Tektronix 4014-1 storage tube. The system is designed to ease conversion to other computers and graphic displays and to interface to other part generation systems with or without databases.

The ADAGE Interactive Nesting and Drawing System is based on the ADAGE GS/300 Interactive Graphics System and a main host computer. The main computer contains the ship design routines, such as AUTOKON, and the Graphics Display System is used to display individual parts calculated by AUTOKON or to draw new parts as may be required, to visually nest these parts on a sheet meal plate, then to display the tool path required to cut the nested parts layout. This Nesting and Drawing package was first developed two years ago as a feasibility study by ADAGE in Italy for a major Italian shipyard, Italcantieri. Since that time Italcantieri has completed the development to the point that it is scheduled to go into production in July, 1976.

Proceedings of the REAPS Technical Symposium held in San Diego, CA on 11-13 Sep 1979.

There are two general subjects that will be covered in this paper - justification of a computerized mould loft for the small shipyard and implementation. The justification will be brief and figures represented in this portion are not actual figures obtained from Port Weller records, but are superficial numbers used only to give the basic ideas of how the eventual purchase of the Autokon system was justified at Port Weller Dry Docks. The implementation portion will be an actual account of our use of numerical control programming starting from December 1973, when the part and nest programs were first obtained from Shipping Research Services.

REAPS AUTOKON has emerged over the last three years as a valuable production tool in shipbuilding. Having its roots in the AUTOKON-71 System developed by Shipping Research Services (SRS) of Norway, REAPS AUTOKON consists of twelve independent computer programs communicating with a common database.

The objective of the Autokon system may shortly be said to be to enable the user to describe in large detail the entire steel structure of a ship or other structure in the database, and extract a variety of design and production data. It should in other words be a "drawing generator" (including information for NC-cutting) but also produce material lists, weight calculations, etc. To fulfill these tasks the present system of routines called norms play an important role. The basis of the present system of norms rests with ALKON, a problem oriented computer language. ALKON maintains a dialog with the Autokon database. It has very extensive features for describing plane geometry. . It is general in nature and may be used to store various types of information on the database. Various data structures may be defined by the user. An ALKON manuscript may be stored temporarily (REP) or permanently (NORM) on the database. This User's Guide will try to explain the philosophy and also give some practical examples in the use of the system. It also gives some basic information which the user needs in order to understand the tool he is using.

Proceedings of the REAPS Technical Symposium. Paper No 3: Navy Manufacturing Technology Program.