Saturday, May 05, 2018

Half Čapek, half Rabbi Leow, part Shelley, and a smidgen of Stoker

kw: book reviews, science fiction, fantasy, robots, golems, automata

Since history began people have dreamed of creating beings like ourselves but from inanimate materials. Equally, myths such as Atlantis, drawn upon by Plato among others, belong to a genre of "The First Men", godlike beings that preceded humanity, or were perhaps our ancestors. Putting all these strains together in one well-written narrative is no mean feat, but in The Clockwork Dynasty, Daniel H. Wilson has pulled it off. The slipcover of the book indicates a Steampunk fantasy, but this is much more.

Peter, or Pyotr, is not a man; his sister Elena is no woman. They are Avtomat, automatons, built long ago and restored by a Russian mechanician. Much of the book follows them in chapters alternating between the 1900's and the 1700's, when they were (re)activated. Later in the book, the flashback chapters land us in about 3,000 BC, when an Avtomat was sheathed in articulated porcelain, much like a golem. Also like a golem, their motivating core, called an anima, embodies a Word; Peter's is pravda (justice), though it eventually turns out to be a much older word of the same meaning. Since that early period, they have taken advantage of improved technology to house their machinery in better "shells".

An Avtomat is faster and stronger than a human—otherwise, what's the use of their production?—and roughly equally intelligent, though perhaps not any wiser. The word "anima" is Latin for "soul", also "breath" or "breeze", and "animal" is derived from Latin for "that which breathes". In The Clockwork Dynasty, though, the anima is much more. It contains the Word and is also the power source of the entire mechanism.

So I'll leave the plot of the story—including wars between rival Avtomat factions over a 5,000-year time span—for the reader to enjoy. In fact, I suggest you read the book first, before reading further in this, because the rest isn't really about the book at all. It's a wonderful book, but it prompted a riff on my part about the energy that is needed by a self-contained robot or Avtomat.

The power needed to run a human body

The "standard" dietary requirement found on most food packaging refers to a 2,000 calorie-per-day diet. Digging around in various resources about basal metabolism, we find that people in the ordinary range of weights need from 1,700 to 2,400 cal/day. At any weight, men need a little more than women. These "calories" are, to a physicist, kilocalories (kCal). The key conversion factor needed is that 1 watt = 860 cal/hr = 0.86 kCal/hr. Over a day this comes to 20,640 cal or 20.64 kCal. Thus 2,000 kCal/day = 97 watts. The day's energy expenditure is thus above 2,300 watt-hours.

This is the standby energy we use because we are warm-blooded. This heat is generated by subtle twitching of all our skeletal muscles all the time, something termed "muscle tone". Animals that aren't warm-blooded, such as reptiles, have much lower energy needs, about 1/5 of what a mammal of similar size might need. And still, much of that is respiration of the living cells in the animal's body. What of a creature that doesn't respire, one that doesn't need to consume oxygen at all?

We may consider an Avtomat is akin to a laptop computer housed in a strong body, and lacking the energy-gobbling screen. Such a being, at rest, may consume no more than a watt or even a fraction of a watt. Of course, that is assuming the memory circuits use similar refreshing technology to that in a cell phone. Perhaps the "First Men" who devised these prehistoric robots had something better.

The energy of work

But when an Avtomat needs to walk, run, work, or fight, it will consume a great deal of energy. A mile walk consumes more than 80 kCal or almost 95 watt-hours. Running the same mile takes about 40% more energy. I remember the fad of the 50-mile hike of the 1960's. Such a hike takes roughly 4,000 kCal, tripling your dietary need that day. If you want to lose weight and be fit, that is a good beginning!

A friend who is a retired lumberjack told me that he and the men he worked with had to eat 8,000 calories daily (8,000 kCal). Subtract resting metabolism, and you find the work consumed about 6,000 kCal, or roughly 7,000 watt-hours. I don't know how much of that energy is consumed regenerating worn tissues, but we can figure that a robot lumberjack that operates similarly to a man will need about a one-horsepower power plant running during working hours.

That may not seem like much, until you consider holding such energy in a battery. Some of the most efficient electrical batteries currently in use are those in laptops and cell phones. A laptop battery weighing a few ounces can deliver about 65 watt-hours. You'd need more than 100 of them to run your robot lumberjack! And they would need recharging every day.

OK, now posit an Avtomat that began with a full charge in about 1700 AD and is still running today, over 300 years later. The anima is described as a device smaller than your hand. Even assuming such a robot isn't hard at work all the day, we're still looking at something over 100,000 days, at a few thousand watt-hours daily. "Only" one kWh/day means the anima has a capacity of at least 100 megawatt-hours. Let's move to physics momentarily: that comes to about a third of a trillion joules (0.36 trillion). Total annihilation of one gram of mass, according to Einstein's equation releases 90 trillion joules. So perhaps the anima begins as a container holding several milligrams of antimatter, plus machinery to meter it out in very tiny doses, and conversion of that energy to mechanical work at great efficiency so that poor Peter and Elena don't burn up during a hard run.

In case you'd rather consider chemical energy release, burning 1 liter of gasoline releases about 7,600 kCal, but only 1/3 of that is usable by the best "heat engines" we have been able to devise. So a liter of gasoline would be needed to run an Avtomat for a day or two, more if it was a lumberjack.

I think that has taken us far enough for now. I hope you read the book before reading this. Such thoughts might ruin the enjoyment of a well-written, page-turner of a narrative about ancient robots.

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