1/ So, feel free to read this thread.https://twitter.com/bara/status/894783903239516160 …
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ⓘ Dogs don't have thumbs Retweeted Alex
1/ So, feel free to read this thread.https://twitter.com/bara/status/894783903239516160 …
ⓘ Dogs don't have thumbs added,
2/ Having done so, I push back strongly on "GPS har har dumb!". I SAID IN THE TEXT IT SWITCHED OVER FROM GPS TO INERTIAL NAV!
3/ My background: * having worked for a defense contractor on GPS-denied navigation for cruise missiles * as a kid, having dad work on >
4/ ...ICBM nav systems, and talking w him extensively re ring laser gyro and other non-GPS (inertial navigation) systems.
5/ I specifically wanted the gravel boats to use GPS on their way in bc the distance from the moon to Earth is such that inertial nav errors
6/ would be too high. I can't find the spreadsheet now, but I did the calculation to find out what thousandth-of-a-second-of-angle >
7/ a target on earth is, as seen from the moon's perspective. Inertial Nav wouldn't cut it.
On the best purely inertial unit I've worked with we measure drift in feet per minute. Without GPS you'd be lucky if the boats hit Haiti.
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