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    Re: New inovation in astro navigation?
    From: Douglas Denny
    Date: 2010 Jul 30, 14:55 -0700

    Dear Ike,

    I hate to be the bearer of bad news, but there is unfortunately a flaw in your reasoning which I am sure others will see too:

    you say: " ....with a digital camera in place of the human eye", and mention various other computer-aided devices; asking: "Does the world need a device that is relatively simple to operate to tell ones rough position in the case of GPS system outage?"

    If there is going to be a device to replace the sextant and almanac in case the electronics and/or battery in the GPS packs-up, then I do not see replacing GPS with another electronic device solves our problem. One might as well buy another GPS as back-up.

    Douglas Denny.
    Chichester. England.


    Original posting:
    As I was sitting here waiting for the phone to ring, a thought popped into my head, in reality a series of thoughts. First was the sad state of choices when it comes to purchasing a new sextant, second was generally agreed idea (at least here) that ships at sea of all sizes need some form of backup to GPS. While I know many of us here enjoy the nostalgic idea of silver inscribed brass arcs , or even precission crafted more modern sextants, and often feel a disdain for things made of plastic, or with excessive technology enclosed. I am wondering if the world is ready for a new inovaiton in astro navigation, my thought is wondering if we have reached a point where technology could help in this quest, digital cameras and computer visual recogntion have came a long way in the last few years (see smile detection on mid range digital cameras, as well as ever increasing light sensitity and resolution).

    One thought I had for such a device would be a sextant like device that removes the fine tuning mechanism and replace it with a system to rigidly lock the arc every 2-5 degrees (whatever the field of view of the mirrors work out to be) with a digital camera in place of the human eye. For noon sites the operator would guess their latitude within a couple of degrees then he just has to point the device so it shows the sun and the horizon at once (this could be a wider view than a tradtional split horizon mirror as the image manipulation could adjust for the separation and count pixels) and then the computer does the rest (well most of it). This is just one idea of how such a device could work, I am sure there are many more, some relying more on software, some on custom hardware, this one I think could be done with off the shelf stuff today. Regardless the underlying point is, Does the world need a device that is relativley simple to operate to tell ones rough position in the case of GPS system outage?

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