Hydraulic Analog Computer From 1949

mbone writes "In the New York Times, there is an interesting story about a hydraulic analog computer from 1949 used to model the feedback loops in the economy. According to the article, 'copies of the 'Moniac,' as it became known in the United States, were built and sold to Harvard, Cambridge, Oxford, Ford Motor Company and the Central Bank of Guatemala, among others.' There is a cool video of the computer in operation at Cambridge University. I remember that the Instrumentation Lab at MIT still had an analog computer in its computer center in the mid-1970s. Even then, it seemed archaic, and now this form of computation is largely forgotten. With 14 machines built, it must have been one of the more successful analog computers — a supercomputer of its day. Of course, you have to wonder if it could have been used to predict our current economic difficulties."

Comments

Computers can't model macroeconomics

[MSTCrow5429]

There is a serious flaw in thinking that computers can accurately model macroeconomics, or predict systematic collapses, any better than commonsense and basic logic can. It is a given that if you massively inflate the monetary supply, you will create a false sense of wealth and a false understanding of risk, and people will malinvest in sectors that they otherwise would have spent far less resources on, or none at all. This is an unsustainable artificially created bubble, and all bubbles burst. Many people saw this coming years, even decades ago, and didn't have supercomputers. People understood this scenario centuries ago, before computers even existed. Using computers as a crutch to make up for a lack of understanding of basic economics is an aggravating factor in the current scenario, not the solution.

Re:Computers can't model macroeconomics

[Trepidity]

I think it's not so much that it can't in theory be modeled, as that in practice it's extremely hard---much harder than modeling the weather, which we can barely do accurately out to 5 days. There's somewhat of a gap in expectations when you go from high-level qualitative descriptions of phenomena, like hurricane experts discussing trends in intensity and formation basins, to an implemented, detailed computational model that purports to simulate what "really" happens. The 2nd one usually diverges extremely quickly from what actually does happen, because these sorts of nonlinear systems are very sensitive to slight errors in the model or its initial conditions.

That's fine, as long as people understand its use and limitations; but there's a tendency, especially among the only-sort-of-technical folks who are involved in a lot of areas of business and economic policy, to trust these computer models as more than they are, as if the fact that a "computer simulation" told you it makes it some sort of neutral third-party truth that represents the state-of-the-art in guessing what will happen.

Re:Computers can't model macroeconomics

[zindorsky]

What they don't realise is that motorists are more intelligent than water particles.

Says you.

Re:Explosives factories

[Thanshin]

Some explosives factories still use hydraulics, steam or vacuum for process control. Although it tends to be digital now, with valves used as flip-flops.

Furthermore, the factory itself can be considered as a digital information storage system.

The problem is returning to the current state after it flips to the other one.

Used in fighter planes

[Maximum Prophet]

Hydraulic computers are used in some military aircraft because they are very reliable and can withstand EMP.

Memory Leak

[SubjectiveObjection]

"Johnny, there's another damn memory leak! Bring the bucket!"

If we would have stayed with this technology...

[sootman]

... the Internet truly would be a series of tubes.

Also, little known fact: Gordon Moore's father was a mechanical engineer who predicted that the size of hydraulic valves would shrink 50% every 18 months.