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IEEE Spectrum has an article about the causes of the recent ISS computer malfunctions...

Quote:

The critical computer systems, it turned out, had been designed, built, and operated incorrectly—and the failure was inevitable. Only being so relatively close to Earth, in range of resupply and support missions, saved the spacecraft from catastrophe.

Wikipedia's page explains that: "Scanimate is the name for an analog computer animation system developed from the late 1960s to the early 1980s."

The Scanimate systems were used to produce much of the video-based animation seen on television between the late 1970s and early 1980s in commercials, promotions, and show openings. One of the major advantage the Scanimate system had over film-based animation and computer animation was the ability to create animations in real time.

"The basic idea...had the simplicity of genius: video has always been constrained to make a rectangular array, identical for both the camera that generates the signal, and the monitor that receives it. Why not play with the voltages that direct the electron beam that paints that image? What could you get with that? How could you steer the beam for a nonrectangular effect?"

"...Scanimate was basically a video synthesizer, set up and adjusted 'on the fly'...used multiple oscillators to drive the video controls to warp and twist the 945-line "high-res" video (hey, in those days, that WAS high-res video). The distorted video was then scanned by a 525-line camera to convert it to standard NTSC video...

YouTube has a trailer for a documentary these guys did about Scanimate called "The Dream Machine".

[url=http://www.fastcompany.com/online/06/writestuff.html]The right stuff kicks in at T-minus 31 seconds.
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As the 120-ton space shuttle sits surrounded by almost 4 million pounds of rocket fuel, exhaling noxious fumes, visibly impatient to defy gravity, its on-board computers take command.

...

But how much work the software does is not what makes it remarkable. What makes it remarkable is how well the software works. This software never crashes. It never needs to be re-booted. This software is bug-free. It is perfect, as perfect as human beings have achieved. Consider these stats : the last three versions of the program -- each 420,000 lines long-had just one error each. The last 11 versions of this software had a total of 17 errors. Commercial programs of equivalent complexity would have 5,000 errors.

...

The group writes software this good because that's how good it has to be. Every time it fires up the shuttle, their software is controlling a $4 billion piece of equipment, the lives of a half-dozen astronauts, and the dreams of the nation. Even the smallest error in space can have enormous consequences: the orbiting space shuttle travels at 17,500 miles per hour; a bug that causes a timing problem of just two-thirds of a second puts the space shuttle three miles off course.

NASA knows how good the software has to be. Before every flight, Ted Keller, the senior technical manager of the on-board shuttle group, flies to Florida where he signs a document certifying that the software will not endanger the shuttle. If Keller can't go, a formal line of succession dictates who can sign in his place.

Bill Pate, who's worked on the space flight software over the last 22 years, says the group understands the stakes: "If the software isn't perfect, some of the people we go to meetings with might die.

Frederick P. Brooks wrote a while ago:

Of all the monsters that fill the nightmares of our folklore, none terrify more than werewolves, because they transform unexpectedly from the familiar into horrors. For these, one seeks bullets of silver that can magically lay them to rest.

The familiar software project, at least as seen by the nontechnical manager, has something of this character; it is usually innocent and straightforward, but is capable of becoming a monster of missed schedules, blown budgets, and flawed products. So we hear desperate cries for a silver bullet--something to make software costs drop as rapidly as computer hardware costs do.

But, as we look to the horizon of a decade hence, we see no silver bullet. There is no single development, in either technology or in management technique, that by itself promises even one order-of-magnitude improvement in productivity, in reliability, in simplicity. In this article, I shall try to show why, by examining both the nature of the software problem and the properties of the bullets proposed.