RUCAPS

RUCAPS (Really Universal Computer Aided Production System) was a computer aided design (CAD) system for architects. It ran on minicomputers from Prime Computer and Digital Equipment Corporation (DEC).

Development

It was developed by two graduates of Liverpool University, Dr John Davison, and Dr John Watts. They took their work to architects Gollins Melvin Ward (GMW) in London in the late 1970s, and developed it whilst working on a project for Riyadh University. It became the the Really Universal Computer Aided Production System (RUCAPS). RUCAPS was later sold through GMW Computers in several countries around the world. It was amongst the leading systems of its time, selling many hundreds of copies at a time when CAD was rare and expensive. RUCAPS was superseded by Sonata and then REFLEX.

The system

In common with many systems at the time, RUCAPS was a building modelling system. To ensure simplicity, it straddled the divide between two dimensions (2D, i.e. flat) and three (3D), by offering what was known as 2.5D. Here, all the elements of the design were placed in space in three dimensions, but each element, such as a window, door, chair or wall, was modelled in a series of 2D views. Usually these views were of the plan and two elevations, each of which were drawn conventionally, as though on the side of a glass box. The "box" was then moved about the design and placed. By looking down on the model the plan view of the whole model was visible, and from the side just the elevation was seen. Because moving the component, or "box", moved both the plan view and the elevations for it, the plans and elevations remained in harmony, and designer's time was saved.

RUCAPS was expensive, as was all CAD at the time, so its use was confined to large building projects. It was then necessary to have several people working on the same model. An early multi-user system was developed, allowing single building models to be worked on simultaneously by many people. It was a system that employed layers, where components were allocated categories allowing groups of them to be switched off or on when the drawings were produced. Layering allowed, for example, drainage to be printed separately from electrical components, but still maintained on the single model.

No clash-detection or calculations were undertaken on the model, but some hiding of one component by another was possible so that external walls showed on elevations while the internal elements were concealled. A perspective drawing system was available as an add-on.