Digigraphics
| Company type | Subsidiary |
|---|---|
| Industry | Computer-aided design software |
| Predecessor | EDM (Electronic Drafting Machine) |
| Founded | 1961 |
| Founder | Adams Associates (Jack Gilmore and Charles Adams), Norm Taylor (Itek) |
| Fate | Division shut down by Control Data Corporation |
| Successor | None |
| Headquarters | Not specified , United States |
Area served | Aerospace industry, US Navy |
Key people | Richard Leghorn, Franklin Lindsay, Jack Gilmore, Charles Adams, Norm Taylor |
| Products | Digigraphics CAD system |
| Parent | Control Data Corporation |
Digigraphics ranks as one of the pioneering commercially available graphical computer aided design platforms. Its origins trace back to Itek, where it was initially created on the PDP-1 under the name EDM (Electronic Drafting Machine). Later, Control Data Corporation acquired this technology and adapted it to their own hardware, introducing a new graphics terminal as part of the package. With a price tag approaching $500,000 and limited support for simultaneous users, the system struggled to compete economically against traditional manual drafting methods, which led to minimal sales.
Origins at Itek
The US Air Force's SAGE initiative was supported by MIT's Lincoln Laboratory, which developed the high-speed Whirlwind computer. This system integrated graphical displays and light pen input devices to enable real-time interaction. Following the conclusion of SAGE, its technological advancements inspired various industry leaders: Ken Olsen established Digital Equipment Corporation (DEC) with former SAGE programmers; Jack Gilmore and Charles Adams founded Charles W. Adams Associates; and Norm Taylor joined Itek, which pursued a computerized photo retrieval system.
In 1959, Gilmore and Taylor proposed a collaborative effort to create a computer system tailored for engineering design. By August 1960, Itek approved funding and contracted Adams Associates to develop the software. The DEC PDP-1, characterized by an 18-bit word length, 4,000-word core memory, optional vector display capabilities, and light pen compatibility, was selected as the host machine.
By June 1961, hardware assembly was finalized at Digital's Maynard plant and subsequently at Itek. The PDP-1 supplied to Itek was only the second commercially delivered unit after one sent to MIT's Project MAC. A 25-inch display tube replaced the standard 16-inch Type 30 model but maintained a similar hexagonal enclosure. User interaction combined light pen pointing with front panel switches that were enhanced by overlays denoting special functions.
To address performance degradation caused by software-driven displays on the PDP-1 as drawing complexity increased, Itek engineered a dedicated "display processor" responsible for screen refreshes. Vector data was stored on the outer tracks of a 36-inch hard disk from Telex to optimize linear access speed, permitting up to 30 frames per second. Vectors were encoded using 4-bit points for greater efficiency. The disk system could accommodate roughly 500,000 18-bit words, with approximately 20,000 bytes allocated specifically for vector information.
Commercial introduction
By early 1962, the core system was operational and marketed by Itek under the name EDM. It attracted considerable attention and was highlighted in a Time feature:
The operator's designs pass through the console into an inexpensive computer, which solves the problems and stores the answers in its memory banks in both digitalized form and on microfilm. By simply pressing buttons and sketching with the light pen, the engineer may enter into a running dialogue with an EDM, recall any of his earlier drawings to the screen in a millisecond and alter its lines and curves at will.
The US Air Force acquired one unit for use at Lincoln Labs, employing the PDP-1 to control their Experimental Dynamic Processor (DX-1). This variant substituted the hard disk with a magnetic drum, improving both performance and storage capacity. It utilized 6-bit words instead of 4-bit points, enhancing resolution and enabling documents up to 2,000 inches in size rather than just 800.
EDM was among several CAD systems under development during that period; for example, General Motors initiated a comparable project in 1959, followed by IBM entering the field in 1960. Although these efforts began around the same time, Digigraphics reached commercial availability approximately one year before IBM's DAC-1.
Acquisition by Control Data
During a period of aggressive acquisitions led by president Richard Leghorn, EDM was offered to Itek. Although Itek was commonly associated with computing ("information technology"), its principal product focused on cameras used in the CIA's CORONA reconnaissance satellites. After a series of unsuccessful acquisitions, Leghorn was succeeded by Franklin Lindsay in May 1962, who proceeded to divest most of Leghorn’s acquisitions, including EDM.
As part of its efforts to broaden its computer product range, Control Data Corporation (CDC) purchased EDM. Adams Associates obtained a contract to adapt EDM for the CDC 3200, while CDC created the CDC 274 terminal operated by the CDC 1700 computer. Subsequent models were compatible with other CDC systems such as the 6000 family, enabling support for multiple terminals per machine.
CDC marketed a limited number of Digigraphics units primarily to aerospace companies like Lockheed and Martin Marietta, and later supplied systems to the US Navy for submarine design projects. After several years of operation, CDC concluded that the venture was not financially viable and subsequently shut down the division.
See also
Bibliography
- "274 Interactive Graphics System Reference Manual"
- David Weisberg, "The First Commercial CAD System", 2006
- David Weisberg, "The electronic push", Mechanical Engineering, 2000