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By Jack Ganssle
Dateline: 28 07N, 68 23W, 350 nautical miles south of Bermuda, 1000 miles east of Florida.
In the 70s I bought a 40 year old wooden sailboat for a pittance. Though at first little more that a floating assembly of wooden boards moored in near proximity to each other, a couple of years of part-time work restored her to near-pristine condition. I replaced the 2080 screws that held her hull together, the deck, the keel bolts, and far more. Eventually, flush with all of $1500 and the optimism of youth, Arwen and I headed south from Maryland to sail around the world.
Though Arwen's purchase and refitting had all been financed by my job as an embedded systems engineer, the boat had nary a single microprocessor on board. In those days stereos, such as they were, used analog tuners. The depth sounder was a piece of lead on a marked line, heaved frantically overboard only when the water looked thin. Even the EPIRB - an emergency radio transmitter that emitted a warble on aircraft distress frequencies - used but a bit of analog circuitry. Not enough, it turned out, to be effective when a container north of Cuba left me drifting in a liferaft. Low tech flares saved the day.
How things have changed. My current boat, built in the same (1977) year Arwen and I left for points unknown, fairly bristles with antenna and electronic systems. As I write this in mid-ocean, a thousand miles east of Florida, bound for the island of Grand Turk, an 8051 in Voyager's autopilot steers. Only my wife and I are aboard so it's nearly impossible to keep a watch all the time, so the radar sweeps silently all night long, emitting a beep whenever a target intrudes within a 10 mile guard zone. The beep is too quiet to alert these sleeping ears, so I've tied the radar into a network. A PIC-based box extracts the beep message and sounds a klaxon. The GPS passes position data back to the radar screen; when a ship appears it takes but a moment to place the cursor over the dot and get the vessel's exact position.
The ham radio's DSP enhances weak signals. Our marine VHF radio scans multiple channels constantly. A digital battery monitor displays the state of charge of the twin 6 volt golf cart cells, and a similarly-smart voltage regulator generates four different kinds of charging regimes to keep the batteries topped off. The utterly-essential Dell MP3 player (fondly christened a "DellPod") feeds 2500 sounds from its hard disk to a smart stereo.
Most astonishing of all is the GPS. It's a small unit, bulkhead-mounted, that constantly shows our position with an accuracy of meters. Once navigation was an arcane art, kept secret by ships' officers so crews couldn't take the risk of mutiny. Now I turn the unit on at the start of the voyage, and do nothing more than watch our position update each second. What Captain Cook would have given for such powerful magic!
Oddly, though, the charts are still crude, many of these remote islands based on surveys from the 19th century. It's ironic that the cheap little GPS is far more accurate than the charts produced at great government expense.
On Arwen I navigated with a sextant, a slice of antiquity that accurately measures angles. Given the angle between the sun or a star and the horizon, plus the time, a bit of math produces a line of position. But there's quite a bit of skill required, and even the best navigators are happy with a mile or two of error. Clouds thwart any sextant sight; over the centuries hundreds of ships and thousands of lives have been lost due to simple math errors and dank, dismal skies.
Today that same sextant lives over Voyager's chart table. I shot the sun and Jupiter yesterday, and reassured Marybeth that the GPS is still working correctly. One wag suggested putting it behind a glass case with a sign "break glass in case GPS fails." But the fact is one can now buy a dozen GPSes for the cost of one good sextant. The technology has truly rendered celestial navigation obsolete.
Poor winds have had us motoring far too much. Voyager's three decade-old diesel is mercifully processor-free, but I've been thinking about building a simple two wire network of epoxy-coated CPUs and sensors to monitor its health.
In the 1500 miles since we left Baltimore the autopilot chewed up a belt. One cabinet latch failed. Fish ate two lures. The engine is leaking just a bit of oil and might need an injector replacement. The anchor light burned out, and one sail needs a bit of attention. But every bit of electronics works flawlessly.
I often rant about the state of the embedded art. Too many systems are unreliable and bug-ridden. Yet even on the anachronism of a sailboat, our lives are improved and coddled by processor wizardry.
One report suggested that the average home has over 200 micros today. Embedded systems are the glue that holds the 21st century together. Frustratingly, few non-techies know what the word "embedded" even means, despite their utter reliance on an implanted pacemaker or smart coffee-maker.
It seems there's always an anti-technology backlash. People move back to the land. They reject the power of science; some yearn for Walden Pond. Me, I embrace the sort of life our smart electronics has created. How about you?