DAC-1
DAC-1 (Design Augmented by Computer) was an early CAD ( computer-aided design ) system introduced by General Motors in 1964 .
The DAC-1 project, initially called Digital Design , was started in 1959 by a group of five. The goal was to develop a computer system for describing the geometry of vehicle bodies. The computer used was an IBM 704 , which was programmed to output graphics on an IBM 780 screen. A chain printer to which five counting disks were wired was used for interactive operation . The current position of the counting disks was read out and controlled the program execution.
The graphical input was made using a photomultiplier tube. Drawings were first applied to a plastic sheet placed over the IBM 780. By identifying the points where the light from a light spot displayed on the screen was obscured, the drawings could be digitized. The digitized curves were smoothed by the computer program and approximated with cubic splines . By interpolating several curves, a surface could be modeled, similar to the Coons patch presented later . In 1960, the cooperation with IBM as part of the project was contractually regulated, whereby the system was supplemented with new hardware.
literature
- Fred Krull: The Origin of Computer Graphics Within General Motors. IEEE Annals of the History of Computing 16, 3 (Fall 1994): 40-56, ISSN 1058-6180
