When the decision was made to proceed with the development of the Interactive Graphics version of the SPADES System, a list of requirements and goals was made. One of the major considerations was to have total interchangeability between the graphic and the batch mode of the System such that rework could be processed easily, whether the original work had been done through the 'CRT' or in batch. As much as we would like to think otherwise, experience has taught us that changes and revisions are an ever present way of life during the ship design and construction process. The requirement was also set that none of the SPADES management and control features would be compromised because of the graphic. In order for the graphic version to be a useful production tool, the user would have the capability of totally checking parts and/or burning tapes generated through the CRT without having to wait for a drafting machine drawing and/or computer printout. It was also decided that the user would have the capability of switching from one program to another directly from the tube without re-initializing any program at the central computer. The plans called for four CRTs to be on simultaneously, and for at least one batch SPADES program to be also running at the same time. This requirement caused the only major modification of the then existing SPADES System in order to allow different programs to read and write records from the same data base at the same time. By combining the use of virtual memory capability of the computer and judicious use of overlay, all the applicable programs have been linked together in one executable module.

The major shipyards that utilize SPADES and Call and Associates have organized a user group. Annual two-day SPADES user meetings are held in danuary of each year to discuss problems and improvements to the system. The SPADES steering committee meets just after the user meeting and again in dune (in conjunction with the REAPS meeting) to make official decisions on problems improvements or changes. At these sessions, priorities for Call and Associates to work toward are established. A problem identification form and a suggestion and improvement form were designed and adopted with a procedure for informing Call and Associates and all SPADES users about changes or problems within the system. Call and Associates assigns a unique identification number to these forms and submits comments. The Steering Committee serves as a catalyst to Call and Associates for constant improvement of the SPADES System.

The use of computers has made a tremendous impact on the ship design and the ship building processes in recent years. Designers utilize special programs to optimize their design according to economic and performance requirements. for a certain type of vessel in a certain type of service. From this iterative process, the optimum parameters are obtained and the preliminary design carried out.

There are numerous ways to define steel parts and each yard favors some subset of these. Interactive graphics is just one of these and not necessarily the obvious best choice right now. Those I know of are: Optical negatives, Digitizing, Part Coding, Part Splitting, Direct ESSI, APT Interactive Graphics. The philosophy differences come in on whether interactive coding should be the best approach toward speeding the process or perhaps using AUTOKON NORMS in a digitizing system or even letting the Design office put the parts in numerical form rather than the Mold Loft. We've also heard philosophy differences on whether the source code or the part geometry itself should be kept as the true record of the part. In other words Parts Definition is different things to different people.

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

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