CARDIAC cardboard computer simulator

I have been meaning to post this for a while.

In the sixties bell labs made a cardboard “computer simulator” which was designed to explain how computers work.

There are quite a few resources for recreating this device and I think it should be used a lot more widely than it is now, and I wonder if something like this would still be used after our industrial civilisation has inevitably kicked the bucket.

ClareBroommaker's picture

No way did I have any computer instruction in school, but, wow does that look familiar-- something from way back in the recesses of my mind.

Blueberry's picture

Clare kinda like the punched card. That goes backed to my youth writing programs in Fortan an Cobol. Some info on punched cards. The good old days locked in a secure room with a IBM 360/370 system.

Justin Patrick Moore's picture

My wife is reading the Difference Engine just now by William Gibson & Bruce Sterling. Maybe things like the CARDIAC and Charles Babbage's machine will be a going concern in declining society, a deindustrialized world.

lathechuck's picture

I recently acquired an intriguing vintage book: "Graphical and Mechanical Computation", by Lipka (MIT), Wiley, 1918. It starts with something as simple as a pair of linear scales, degrees C on one side, degrees F on the other. You "compute" the conversion by find the value you have on the appropriate scale, then reading across to the other. (This could be done with a printed table, but it's easier to interpolate between the marked numbers when it's in graphical form.) With non-linear scales, you can do the same thing for any function: sin(x), tan(x), log(x), and their inverses, depending on which scale you find the value that you know. Then, it's on to scales that slide, the famous log-log slide rule for multiplication and division, and even finding solutions to quadratic and cubic equations. (I haven't seen that in any introductory slide-rule instructions.) It goes on to describe the construction of various warped-grid (my term) plots for solving chemistry and engineering problems. Eventually, we end up with mechanical devices for plotting a curve which is the integral (or derivative) of some other curve. These plots can then be read to solve particular problems regard the integrated (or differentiated) functions.

Computing Mechanisms and Linkages (Svoboda, McGraw-Hill, 1948) describes the design of machines which perform "calculations" in which an output movement is a required function of one or more input movements. For example, adjust the elevation and azimuth of a large gun, based on a setting of the projectile weight, desired range, wind speed, powder charge, visual bearing to target, etc. (Don't forget to take the Coriolis Effect into account.) Perhaps this sort of thing could also be used to set the pitch of a wind-turbine blade, given the current wind speed and the desire to pump the maximum amount of water.

None of the computing devices described in these books will perpetuate the provision of cat pictures through the population, however.