Early autopilots, the motivation
Check out this recent entry in Maine Boats, Homes & Harbors great series of retro ads. It dimly reminded me of autopilots on the old fishing boats I spend time around in Gloucester, Mass., back in the late 70’s. Some were still using strange schemes to derive electrical signals from a tradition card-in-fluid compass, like a light shining through a hole in the edge of the card to a series of photo-electric cells arrayed in a circle beneath. The Photo-Electric Pilot didn’t make it to the Internet, but I did come across this amazing bit of related marine electronics history:
In 1926, Wood Freeman was salmon trolling along the Pacific Northwest Coast when a boom broke loose, struck him, broke his jaw in three places and knocked out his teeth. Unable to remain standing, he lay on the galley table for three days and steered the vessel home with his feet while watching the ship’s compass in a mirror balanced on his chest.
During his recovery, Wood — an experienced mining engineer and college chemistry professor — began designing a reliable automatic steering system. Popular but unreliable techniques of the day included steady sails, sea anchors and fishing lead on a trailing line connected to the tiller. Wood continued commercial fishing while working to perfect his steering system. He experimented with magnetic compasses and various ways to detect course error (including fluid conductivity, photoelectric sensors and mechanical pick-off) before determining the best available detection method: fine wires with physical contact on the compass card itself. In 1934, he installed and operated his first production unit, the Metal Marine Pilot Model 1, on the commercial fishing vessel Jean.”
You can learn more at WoodFreeman. Meanwhile, I’m off to San Diego for the NMEA Conference. Write if there’s something particular I should look into at Thursday’s exhibit, and especially if you have questions about DSC and AIS for Ghassen Khalek of the FCC (meeting announced here). I’ve got a couple of interesting boat trips lined up to. Westward ho!
The magnetic compass, yay or nay?
August 30, 2005
Swingship, and getting a compass right
September 8, 2005
New Simrad Autopilots, 100% NMEA 2000, almost
November 9, 2007
March 9, 2004